valve train clearances and problems

grumpyvette

Administrator
Staff member
you might want to read thru these links and sub links it will help you avoid costly mistakes

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http://www.summitracing.com/parts/pro-66830/overview/
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https://www.harborfreight.com/multipositional-magnetic-base-with-fine-adjustment-5645.html

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https://www.harborfreight.com/catalogsearch/result/index/?dir=asc&order=EAScore,f,EAFeatured+Weight,f,Sale+Rank,f&q=indicator+stand

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almost every mechanics tool box needs a few basic measuring tools and supplies

If you suspect a worn cam lobe, checking the cams lobe lift with a dial indicator on the valve spring retainer vs the other lobes would certainly provide useful related info.
knowing vs guessing helps in making decisions wisely

http://www.summitracing.com/parts/pro-66830/overview/
pro-66830_cp.jpg



https://www.harborfreight.com/multipositional-magnetic-base-with-fine-adjustment-5645.html

bv93fans.jpg

https://www.harborfreight.com/catalogsearch/result/index/?dir=asc&order=EAScore,f,EAFeatured+Weight,f,Sale+Rank,f&q=indicator+stand

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https://www.amazon.com/Claytoon-Set...d=1466872286&sr=8-17&keywords=plastilina+clay

http://www.utrechtart.com/Plastalin...currency=USD&gclid=CN3G75zOw80CFQgaaQodKbgFjA
When checking valve spring installed height and valve clearances you can,t guess,.its mandatory you don,t guess and actually measure clearances, valve spring micrometers are not expensive and owning or borrowing one for your engine assembly makes a good deal of sense, you can get close with SNAP GAUGES, and a 2" standard micrometer or a vernier caliper, while valve springs won't increase lift, (thats dependent on cam lobe and the rocker ratio) the proper combo of shims, retainers, valve springs, and keepers and in some cases longer valves can effectively increase valve train clearance
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all turbo and super charged engines, bring into play an additional factor when you set up your engines valve train, and select valve springs.
you might want to change too or select better and upgraded valve springs simply because a boosted or supercharged engine obviously has pressure in the intake runners and what most guys fail to understand is that that means theres about 3.2 square inches of intake valve and if theres 10 lbs of boost the result is it requires about 30 lbs more effective spring seat pressure to firmly seat the valve on its seat at higher rpms,add the fact that valve springs lose tension over time bue to heat and constant stress and your 100% sure to see a loss of consistent valve train component control, at a lower rpm than the identical cam used without boost, with identical spring installed height and seat and full lift load numbers.
if youve ever stuck your thumb over a garden hose trying to stop the water flow youll realise that sealing it against flow requires a good deal of force

If your ordering any cam, be very sure you explain what year block and what cylinder heads will be used as there are differences in the cams. between early and later SBC, block s and the cams they require,and on big blocks theres similar issues, a mark VI cam is different from a MARK IV cam

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http://www.grumpysperformance.com/flowridge1.png[\img]
any time you change cams youll need to use a matching distributor gear, the cam manufacturer should be able to help tell you what matches, obviously checking clearances helps
and dipping the gear in moly assembly lube before it installed helps
be sure you inspect the distributor gear for excessive wear
especially if you changed from a flat tappet to a roller cam.
if your seeing the timing change a few degrees, back and forth,
slack in a worn, loose timing chain, worn distributor gear or not having the proper shim clearance on the distributor center shaft will provide slop that allows timing to vary several degrees
http://www.kmotion.biz/instht.htm


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there are PLUS .050, standard and NEG .050 height retainers and valve cups and shims to adjust the installed valve spring height and location in regard to the cylinder head and valve guides
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If the valve springs are to be removed with the heads still on the car,

the last thing you want is too remove a valve spring and have the valve to drop into the cylinder,
if you use air the crank tends to want to spin the crank to BDC, youll want to verify TDC ,
and make sure the flywheels temporarily prevented from turning from that the TDC position,
Ive used both methods both work,you can put 6 ft of rope in the cylinder while its in BDC then turn it to TDC, Ive used both with zero issues,
If you use the compressor youll want to keep it at 120 psi and constantly feeding pressurized air to keep the valves held in place,
and theres a small chance the compressor pushes enough moisture to allow water to accumulate in the cylinders,
so be sure you spin the engine with the starter with the spark plugs removed several times before you re-install plugs.
if you use the rope, theres a very low chance that the rope will tangle and form a knot that makes removal difficult

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http://www.lunatipower.com/Tech/Valvetrain/HowToVerifyValvetrainGeometry.aspx

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http://garage.grumpysperformance.co...alves-and-polishing-combustion-chambers.2630/


http://garage.grumpysperformance.co...ck-chevy-gen-v-vi-to-adjustable-rockers.4564/


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http://www.summitracing.com/search/...d-length-checkers?autoview=SKU&ibanner=SREPD5
Proform Pushrod Length Checkers 66789 SBC 3/8" rocker studs

Proform Pushrod Length Checkers 66790 SBC 7/16" rocker studs

Proform Pushrod Length Checkers 66806 BBC 7/16" rocker studs

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Parts List for Ask Away: Big Block Chevy 454 Pushrod Length​

Part NumberDescription
CCA-7702-1COMP Cams Hi-Tech Pushrod Length Checking Tool,
6.80" - 7.80" (Intake)
CCA-7703-1COMP Cams Hi-Tech Pushrod Length Checking Tool,
7.80" - 8.80" (Intake)
CCA-7704-1COMP Cams Hi-Tech Pushrod Length Checking Tool,
8.80" - 9.80" (Exhaust)
CCA-7900COMP Cams Magnum Checking Pushrod Set*
*Master Kit: five separate adjustable pushrods from 6.125" to 11.50".
***
heres a bit of useful related push rod length info
Big Block Chevy, Standard Length Big Block Intake 3/8" / .080" 8.275"
295-7941-8 Big Block Chevy, Standard Length Big Block Exhaust 3/8" / .080" 9.250"
295-7969-8 Big Block Chevy, Standard Big Block +.100" Long Intake 3/8" / .080" 8.375"
295-7979-8 Big Block Chevy, Standard Big Block +.100" Long Exhaust 3/8" / .080" 9.350"
295-7951-8 Big Block Chevy, Standard Length Big Block Tall Deck Intake 3/8" / .080" 8.675"
295-7961-8 Big Block Chevy, Standard Length Big Block Tall Deck Exhaust 3/8" / .080" 9.650"
295-7800 V8 396-454 Retro Fit Pushrod Set, Intake & Exhaust, 1965-Present
3/8" / .080"
3/8" / .080" 7.725 Int.
8.675 Exh
295-7913-16 Small Block Chevy, Standard Length Small Block Chevy 3/8" / .080" 7.800"
295-7984-16 Small Block Chevy, +.100" Long 3/8" / .080" 7.900"
295-7934-16 Big Block Ford, Standard Length Ford `72-'78 429-460 3/8" / .080" 8.550"
295-7951-16 Big Block Ford, Standard Length Ford `69-'71 429-460 3/8" / .080" 8.675"
295-7582-16 Oldsmobile, Std Length 455 5/16" 9.550"




http://www.racingsprings.com/

preventing cam & lifter break-in failures
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watch this video, it depicts the lifters movement as the cam lobe rotates under its base forcing it up as the lobes ramp, rotates under the lifter base,removing the clearance slack,
as it compresses the valve spring and forces the trapped oil, up the push rod and lifts the valve
If you are concerned with measuring the clearance in the hydraulic lifter seat when selecting and measuring the correct valve train geometry,
so you can order the correct length push rods...
I don,t think you have the correct idea as to how hydraulic lifters work,
yes it is possible for an engine with hydraulic lifters to be pushed too operate at a high enough rpm that the time required for the lifter seat to fully depress and all the oil too be forced up to the push rod/rockers , to be so short that the lifter pumps up and the valves will have less seat time, ( sometimes one of several factors, like the lifter leaving the cam lobes surface as the inertial loads exceed the valve springs ability to maintain lifter too lobe contact, referred too or contributing to what is commonly referred too as valve float) but that has ZERO to do with selecting push rod length or proper valve train geometry, (remember at 6000 rpm the valve is lifted off its seat 50 times PER SECOND)

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it only takes a few seconds running a new engine for an improperly installed cam , lifters and valve train, during the break-in process to generate teaspoons of metallic trash that ,once in the engine oil flow ,rapidly destroys bearings if the clearances ,spring load rates or valve train geometry is wrong

it should be rather obvious that there's options,you'll chose in both valve train components and lubricants, cam failures are usually the result of incorrect CLEARANCES or too much SPRING PRESSURE or LACK of ADEQUATE LUBRICATION,USE DECENT MOLY CAM LUBE, and decent quality oil, adding MAGNETS to trap metallic CRUD HELPS, if your not getting constant oil flow from each rocker /push rod at idle theres something wrong and that needs to be checked
yeah! as I stated it varies with engine cam used and application,yes BBC valve springs tend to be larger as the valves weigh more, but generally theres not a huge amount of compression during the install and obviously the cam generally comes with the installed height, valve spring part numbers and intended load rates that should be used, and yes you still need to use shims, valve spring cups and watch out that at max lift you still maintain the required clearances
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BEEHIVE SPRINGS GIVE A GOOD DEAL MORE ROCKER TO RETAINER CLEARANCE

if you change the rocker ratio the push rod alignment changes and you might need a LUIS TOOL to lengthen the cylinder head clearance slots in the cylinder heads.

be sure to check clearances carefully like coil bind,and push-rod to guide plate alignment and clearances ,verify the rocker slots don,t bind on the rocker studs as this is a common problem with stock stamped style 1.6:1 ratio rocker, verify the push rods don,t bind in the slots in the cylinder head, if they do even for an instant at one point in the rockers arc, they can bind the lifter rotation on the cam lobe and cause the cam to wipe, out the lobe and the lobe & lifter contact area resulting in a quickly failed cam,and/or restrict oil to the rockerss

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check all valve train geometry and clearance on any engine you assemble or modify the valve train on.
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READ

http://rehermorrison.com/tech-talk-86-spin-and-win-evaluating-valvetrains-the-old-fashioned-way/

http://www.hotrod.com/techarticles/engi ... index.html
these adjustable push rod guide plates come in handy at times
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(1) get a decent ROLLER CAM, add a high volume oil pump, baffled 8 qt oil pan, with a windage screen and check your clearances and avoid the problem,USE DECENT MOLY CAM LUBE,and decent quality oil,adding MAGNETS to trap metallic CRUD HELPS


(2) use a SOLID lifter flat tappet cam with lifters with the lube feed holes,add a high volume oil pump, baffled 8 qt oil pan, with a windage screen and check your clearances and avoid the problem,USE DECENT MOLY CAM LUBE, and decent quality oil,adding MAGNETS to trap metallic CRUD HELPS


http://www.competitionproducts.com/prodinfo.asp?number=651080DL

(3) mod the lifter bores for more oil flow,add a high volume oil pump, baffled 8 qt oil pan, with a windage screen and check your clearances and avoid the problem,USE DECENT MOLY CAM LUBE,and decent quality oil,adding MAGNETS to trap metallic CRUD HELPS


http://www.compperformancegroupstores.c ... gory_Code=


(4)USE DECENT MOLY CAM LUBE

http://www.cranecams.com/index.php?show ... l=2&prt=15 ,
add a high voluum oil pump, baffled 8 qt oil pan, with a windage screen and check your clearances and avoid the problem,and decent quality oil,adding MAGNETS to trap metalic CRUD HELPS


(5) thinking things thru and verifying clearances and spring pressures, and having a well thought thru lube system will significantly lower your chances of having problems,USE DECENT MOLY CAM LUBE,and decent quality oil,adding MAGNETS to trap metallic CRUD HELPS
.......I have not seen a cam fail in years UNLESS the guy installing it failed to follow those tips
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https://www.ebay.com/i/402584062207...1291&msclkid=d17e7155654a1a20769a115a09f43c68


if the lifter base is well worn you can bet the farm the cam lobe is most likely also worn, and you'll need a lifter removal tool to pull the damage lifters up out through the blocks lifter bores
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The following recommendations are from Erson Cams.
If you have questions, you can reach their tech department at 800-641-7920.
most cam manufacturers do extensive testing with each engine design to verify the limits and limitations of each engines valve train design, so it generally helps to talk with the cam suppliers tech department engineers.
cam lobe acceleration / de-acceleration rates have a large effect on the required spring load rates, as do rocker ratios and cam lobe size and lifter diameters.
Hydraulic Flat Tappet Camshaft: 110 lbs Seat pressure/250-280 lbs open pressure

Solid Flat Tappet Camshaft: 130 lbs Seat Pressure/300-325 lbs open pressure

Hydraulic Roller Camshaft: 130-140 lbs Seat Pressure/300- 355 lbs open pressure

Solid Roller Camshaft: (Minimum Safe Pressures DEPEND ON SEVERAL FACTORS)

Up to .600Ë valve lift: 200-235 lbs Seat Pressure/600 lbs open pressure

Over .600Ë valve lift: 250-280 lbs Seat pressure /100 lbs pressure for every .100Ë of valve lift

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many more modern oil formulations lack the correct additives for flat tappet lifters, so be very sure you check to see what oil your using and if its designed for flat tappet lifter applications
Id also point out that youll want to lubricate any valve you install in a valve guide and verify the valve train clearances very carefully, and use the correct valve springs and add the correct valve seals installed

anyone see a PATTERN?
http://garage.grumpysperformance.com/index.php?threads/removing-valve-seals.4283/
you might want to read thru this AGAIN
http://www.highperformancepontiac.com/t ... index.html

http://www.cranecams.com/?show=article&id=2]http://www.cranecams.com/?show=article&id=2

FROM MORTEC
If you are building a SMALL or BIG block Chevy with a flat tappet cam, (solid or hydraulic lifters) be careful during the initial engine break in. It is very easy to lose a cam lobe and lifter during initial break in. This is especially true with a higher than stock lift cam and higher pressure valve springs. The increased push rod angles found on the BBC and poor preparation can make cam lobe failure after initial fire up a distinct possibility. You can help prevent this cam lobe failure by making sure the engine is pre-lubed prior to initial fire up. Use a good high pressure lube on the cam lobes and lifter bottoms during assembly. If possible use a lighter pressure stock valve spring (or if using a valve spring with multiple springs, take out some of the inner springs) to initially run the engine. Then switch to the heavier pressure springs after break in. When the engine is first fired up, keep the engine rpms at 2,500 or above, don't let the engine idle for 20 minutes or longer. This keeps lots of oil splashing up on the cam lobes. Make sure the engine can be run for this time period by having enough fuel available, ignition timing set correctly, coolant available for the motor, valve lash set correctly, etc. The idea is not to crank the motor over excessively before it starts up for the first time. If your BBC flat tappet cam survives this initial break in period, it will be good to go for many miles. After the initial engine break in, drain the oil and change the oil filter. Roller cams generally do not suffer these types of cam lobe failures during initial engine fire up.
if you've adjusted the valves correctly the lifter spins at all rpm levels,but that does NOT mean it wears EVENLY at all rpm levels due to several factors if you look closely AT FLAT TAPPET CAMS you'll see that the center of the cam lobe is NOT centered under the lifter and that the lifter surface is slightly angled , BOTH these factors force the lifter to spin in its bore as the lobe passes under the lifter slightly off center.
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SOME of the reasons the higher rpm durring the break in phase is important is that

(1) the faster RPMs the better chances the lobe passes under the lifter floated on an oil film and the less time the oil film has to squeeze out between them

(2) the higher the RPM the greater the oil volume and pressure the engine pumps and the more oil flow is available at the lobes

(3)the higher the rpm level the more oil is thrown from the rods onto the cam lobes

(4)the higher the rpm the greater the lifters weight and inertia tends to compensate for the springs pressure and lower the net pressure as the lifter passes over the cam lobes nose

(5) at higher rpm speed the better chance a small wedge of oil is trapped between the lifter base and lobe from the oil thrown from the lobes surface by centrifugal force

(6) two different metal surfaces scraping past each other at low speeds may tend to wear and GALL as the oil is squeezed out but two different hardness steel surfaces that impact each other at higher speeds covered with oil tend to work harden as they mate and will tend to be separated by that oil

(7)as the lifter spins in its bore the contact point between the lobe and lifter base constantly changes and rotates with the lobe contact point not resisting its passage and the higher the rpms the faster the lifter rotates and the less time the lobe spends at any one point

BTW ADD E.O.S. to the oil and MOLY break-in lube to the cam
before starting the engine and pre-fill the filter and pre-prime the oil system before starting the engine.
I normally pour it in just before starting the engines cam break in,procedure. because I want to make sure that nothing in the oil/E.O.S. mix can settle out from sitting over a long period of time. now if your running a flat tappet cam you should have also used a moly cam lube on the lobes and be useing a mineral base oil for the break-in procedure, and youll need to do an oil and filter change after about the first 3-4 hours running time to remove that moly cam lube from the engine after its served its purpose of protecting the cams lobes and lifters at start up, aND AS THE LOBES/LIFTERS LAPPED IN. MOSTLY to prevent that moly grease and E.O.S from potentially partially clogging the filter after that mix cools down,but also because both those lubes might leave deposits in the combustion chamber ,over time that might aggravate detonation.
even G.M. suggests that E.O.S. is not a great long term oil supplement, and that its main function is to add extra oil film strength durring new engine break in.
Isky claims that the Comp XE cams violate the 47.5% rule. The 47.5% rule applies to flat tappet cams for SBCs with 1.5 rockers but the concept is still the same for other configurations where the designs are "on the edge" or "over the edge" for lobe intensity. For 1.5 ratio SBCs, the duration at .050 must exceed 47.5% of the total valve lift or your asking valve train problems. For example, take a Comp Cams Magnum 280H, with 230 duration and, 480 lift...230/.480 = 47.9% which exceeds 47.5% therefore would not pose a threat to components. We do not regularly hear about the older, safer HE and Magnum designs rounding off lobes anywhere near as often as the XE cam designs. Unfortunately, some of the Comp Cams XE dual pattern lobes break this 47.5% rule on the intake side so they are likely to be problematic. The design has "steeper" ramps that are too quick for durability and reliability according to other cam manufacturers. They will wipe lobes in a heart beat especially if you have not followed the proper break-in procedure. Other designs are more forgiving during break-in and less likely to fail.
http://www.gmpartsdirect.com/results.cf ... number=EOS
STOCK dog bone design hydraulic enclosed wheel roller lifters are generally designed for less than .550 lift and less than 6000rpm
the stock Chevy hydraulic roller lifters , dog bone and spider springs don,t always work reliably, ALL THE TIME with engines having over .500 lift or when spun over 6000rpm, its not all that rare for the lifter ,retainer to bend the retainer spring allowing the lifter to spin sideways, in the lifter bore, resulting in a destroyed cam, thats why Ive suggested BRAND NAME ,AFTERMARKET RETRO FIT CAM COMPONENTS BE USED

Question?
why use stock lifters when there are lots of much better quality hydraulic retro-fit lifters with significantly better potential rpm capability for not much more money? even if you were going to pay $200-$300 more for the linked hydraulic roller lifters, they have a significant advantage in that they don,t tend to have issues with the lifter retention spider or dog bones failing
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the aftermarket linked lifters tend to handle valve lifts exceeding about .500 and rpm levels exceeding about 5800 rpm much better and with fewer issues
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while I generally use stainless 6 or 8 mesh screens theres lots of options that will work just fine, just remember to keep the oil changed regularly or theres some potential for sludge to clog ANY size shrapnel screens
http://www.twpinc.com/twpinc/products/T ... 6T0350W36T
http://www.twpinc.com/twpinc/products/T ... 8S0280W36T
while I generally use stainless 6 or 8 mesh screens theres lots of options that will work just fine, just remember to keep the oil changed regularly or theres some potential for sludge to clog ANY size shrapnel screens
http://www.twpinc.com/twpinc/products/T ... 6T0350W36T
http://www.twpinc.com/twpinc/products/T ... 8S0280W36T
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http://www.summitracing.com/parts/mor-25026?seid=srese1&gclid=COOf2IODscgCFZKAaQodHWoF1Q
it should not take a great deal of imagination to see that a broken rocker, lifter or push-rod could dump metalic debris into an oil drain back port that wold rapidly result in increased internal engine damage as a result.
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Something like this, placing magnets and shrapnel screens helps engine durability red ones in drain valley, green ones being overkill/optional?


yeah thats logical magnet locations,
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IVE typically used these magnets in an engine, one in the rear oil drain on each cylinder head, one near each lifter gallery drain and 4 in the oil pan sump
proper magnets trap metallic debris
SmCo Samarium Cobalt Disc Magnets
http://www.magnet4less.com/

http://www.summitracing.com/parts/mor-25026?seid=srese1&gclid=COOf2IODscgCFZKAaQodHWoF1Q
it should not take a great deal of imagination to see that a broken rocker, lifter or push-rod could dump metalic debris into an oil drain back port that wold rapidly result in increased internal engine damage as a result.

Something like this, placing magnets and shrapnel screens helps engine durability red ones in drain valley, green ones being overkill/optional?


yeah thats logical magnet locations,





IVE typically used these magnets in an engine, one in the rear oil drain on each cylinder head, one near each lifter gallery drain and 4 in the oil pan sump
proper magnets trap metallic debris
SmCo Samarium Cobalt Disc Magnets
http://www.magnet4less.com/
http://garage.grumpysperformance.co...-the-extra-cost-vs-a-flat-tappet-design.3802/

http://garage.grumpysperformance.co...er-lifter-install-direction.11398/#post-52208

http://garage.grumpysperformance.co...-rockers-and-the-pushrods-rub.198/#post-46839

http://garage.grumpysperformance.co...ng-pressures-don-t-work-well.1489/#post-36984

http://garage.grumpysperformance.com/index.php?threads/brand-x-vs-brand-y.8077/#post-27919

http://garage.grumpysperformance.co...ting-up-the-valve-train.181/page-2#post-19781

http://garage.grumpysperformance.co...ulic-roller-lifter-cam-dyno-comparison.12449/

http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-57678

http://www.ebay.com/itm/Lunati-7233...ro-Fit-Hydraulic-Roller-Lifters-/142214244725

http://www.ebay.com/itm/Howards-Cam...c-Roller-Lifters-V8-350-400-383-/330913878812

http://www.ebay.com/itm/HOWARDS-SBC-Chevy-Retro-Fit-Roller-278-284-500-510-114-Cam-Camshaft-Lifters/111898314084?_trksid=p2047675.c100005.m1851&_trkparms=aid=222007&algo=SIM.MBE&ao=2&asc=44730&meid=fc5419dec13f4dbd94f133f935466820&pid=100005&rk=2&rkt=6&mehot=lo&sd=111898309401

don,t forget a few magnets in the oil pan goes a long way towards trapping unwanted metallic dust formed from the cam and rings lapping in durring break-in that might otherwise get embedded in your bearings or cause other problems
here is the magnets I use in every engine
add a few magnets to the oil pan and drain back area in your engine, the trap and hold metallic dust that comes from wear and increase engine life span by preventing that crap embedding in the bearings

http://www.kjmagnetics.com/proddetail.asp?prod=D66SH

http://www.kjmagnetics.com/proddetail.asp?prod=D66SH

http://www.kjmagnetics.com/proddetail.asp?prod=D82SH

these are even more tolerant of temp swings and retain strength at even higher engine oil temps plus they are smaller and easier to use

http://www.cranecams.com/?show=reasonsForFailure

https://www.holley.com/data/Products/Te ... NST150.pdf

http://www.circletrack.com/techarticles ... index.html

http://www.cranecams.com/?show=camQuestions

stuff like this is easily avoided or fixed if you have the correct tools and experiance, BBC engines tend to require extra care during the break-in due to high lifts and strong valve springs, I tend to smear MOLY cam lube over all the valve train surfaces, break the cams in at 2000-3000 rpm and use crane break in lube also, and run a decent high zinc content oil during the first few hours

yeah, check it out, the longer you run it if the lobes are wearing the more crud your pumping thru the engine,if you did lose a lobe its USUALLY a clearance issue like spring bind, rocker to rocker stud, or retainer to valve guide , improper lash/pre load or installation issue like the wrong spring loads or improper lubrication.
stock springs and rocker to valve stem clearance on some BBC heads won,t clear more than about .530 lift, many clear .560, but above that you almost always need to check carefully, or use aftermarket valve train components and custom machine work

the old familiar stuffs Part #1052367 is getting hard to find
E.O.S. was discontinued but.....
http://www.sdparts.com/product/1052367/GMEngineOilSupplimentEOS16ozBottle.aspx
the new stuff...
http://www.acdelco.com/html/pi_vehcare_lub.htm
(use the drop down menu)
Part 10-106
12371532
E.O.S. Assembly Lubricant (1 pint)

its still available if you know where to look, most but not all parts counter guys will know this but youll run into a few who just insist its not available

http://www.cranecams.com/?show=promo&id=48


btw MOLY base lubes are your first and best break-in lube during the first few minutes

http://www.cranecams.com/index.php?show=browseParts&lvl=2&prt=15

http://www.cranecams.com/pdf/548e.pdf


http://www.carcraft.com/techarticles/11 ... index.html

CRANES Super Lube Break-In Concentrate is an anti-wear additive formulated with a high concentration of special zinc dithiophosphate to provide sustained protection against cam lobe and lifter scuffing and wear. This oil supplement is to be added to the engine oil for the initial break-in period after the installation of a new camshaft and lifters.

Part No. 99003-1 -- 8-ounce container

http://www.digitalcorvettes.com/forums/showthread.php?t=84348

BTW before the next time you do a running valve adjustment you should find and use a set of cheap used tall valve covers which youve modified by cutting a wide slot along the center top surface, this retains a good deal more oil in the engine vs on the headers,but before assuming anything verify the old cam is having problems and your clearances/geometry on the valve train are correct

IVE always preferred STEEL roller rockers over ALUMINUM for two reasons
first STEEL has a MUCH GREATER fatigue life under repeat stress than aluminum, and steel generally has far fewer clearance insures with other components, plus some STEEL roller rockers are REBUILD ABLE

http://store.summitracing.com/partdetail.asp?part=CCA-1302-16&autoview=sku


http://store.summitracing.com/partdetail.asp?part=CRN-11600-1&autoview=sku

in MOST cases you can install 1.6:1 roller rockers with MINOR machine work, (I have seen on rare occasions no machine work necessary)
but in any case its easily done,

the tool comes with instructions

http://store.summitracing.com/partdetail.asp?autofilter=1&part=PRO-66485&N=700+115&autoview=sku

and before a dozen guys start telling you they installed them with zero problems on stock heads, keep in mind most guys don,t take the time to check ALL the clearances thru THE FULL rotation of the rockers arc. and it they don,t break or bind parts ,THEY assume its fine
but the truth is the push rod should NEVER touch either end of the slot even lightly anywhere in the arc.


WATCH THE VIDEOS, READ THE LINKS

http://www.youtube.com/watch?v=Cqx8Cs6O ... re=related

http://www.youtube.com/watch?v=5GBNLlsi ... re=related
http://www.digitalcorvettes.com/forums/showthread.php?t=82474

https://www.centuryperformance.com/valve-adjustment-procedure.html

http://www.2quicknovas.com/happycams.html

http://www.iskycams.com/camshaft.php

http://www.reedcams.com/degreeing.htm


http://garage.grumpysperformance.com/index.php?threads/multi-angle-valve-job-related.3143/#post-8387

http://garage.grumpysperformance.co...video-with-info-worth-watching-through.15999/


keep in mind shims under the valve springs can be used to raise the spring or shorten the valves installed height, valve locks and retainers can be purchased with non-O.E.M dimensions to adjust the valves installed height or spring load rates
you use either or both depending on the application
a .050 PLUS valve lock moves the retainer .050 higher on the valve stem with no other changes, a plus .050 retainer would move the retainer .050 higher with stock valve locks or an additional .050 if matched to .050 plus locks
if you used a plus .o50 retainer with a set of minus .o50 valve locks the retainer would remain at the stock height on the valve stem

Ive used CROWER,ERSON,CRANE and HERBERT valve springs but the source I use the most is these guys, (below) so Id at least suggest you look over the options, and choose what suits the budget and needs of the engine, and yeah! everything thats decent quality costs a great deal more money that you expect it too as Im all too sure that you know all too well.
http://www.racingsprings.com/
(866) 799-9417
http://www.racingsprings.com/Staff
heres their ph#
Toll Free (866) 799-9417
I always just order the springs. retainers. valve locks. and spring seat cups & shims as a package deal (NOT CHEAP BUT EVERYTHING WORKS AND FITS) then you just need shims under the valve spring seats occasionally to get the correct installed height


THREADS THAT MIGHT HELP
http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/


http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.co...-loads-and-installed-height.10709/#post-46658

http://garage.grumpysperformance.com/index.php?threads/busted-valve-spring.7716/#post-29797



HERES OTHER TOOLS YOU MIGHT NEED
pro-66775_w.jpg

valve spring compressors
pro-66832_cp.jpg

pro-66784_w.jpg

6781.jpg

77866902.jpg


vspr1.jpg


drawsdf.jpg

yes I'm aware a few guys would prefer being skinned alive and dipped in alcohol to reading links!
but for those guys who care to learn more these links might be useful

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/valve-springs.9613/#post-50534

http://garage.grumpysperformance.co...-loads-and-installed-height.10709/#post-46662

http://garage.grumpysperformance.co...u-buy-bare-or-assembled-heads.534/#post-41292

http://garage.grumpysperformance.com/index.php?threads/busted-valve-spring.7716/#post-38047

http://garage.grumpysperformance.co...pring-cooling-via-engine-oil.6491/#post-20681

http://garage.grumpysperformance.com/index.php?threads/vortec-spring-upgrade.6175/#post-19304


http://garage.grumpysperformance.com/index.php?threads/checking-piston-to-valve-clearances.399/

http://garage.grumpysperformance.co...per-valve-spring-seats-shims.1005/#post-15534
 

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grumpyvette

Administrator
Staff member
MARVEL MYSTER OIL is a good high detergent oil designed to aid valve train and rings ETC. cleaning, I almost always add about 10% marvel mstery oil to my engines, but if your running flat tappet lifters Id point out that many current oils are designed for roller lifter engines so Id sellect an oil thats designed for the older design with the higher zinc content, and adding a can of E.O.S. to the oil and moly assembly lube on the lifters and cam, sure won,t hurt on that first break in, if your breaking in the engine in your driveway, have a running hose and a fan handy, water running thru the radiators cooling fins and a fan blowing air helps prevent over heating, have a timing light and USE IT, check your fluid levels and watch your gauges
on that other issue, of bent push rods, Id suggest you look into that as it takes hundreds of lbs of force and usually some component in the valve train or piston to valve contact to bend a push-rod and if that much force was applied somethings binding or somethings been badly clearanced.
before, you start reading through the thread and links below, Ill point out that I,ve done the forensics on quite a few failed cams over the years that guys have brought to my shop and Id say about
60% of the failed cam lobe & lifter problems were traced to a failure to check clearances or correct valve train geometry issues , like coil bind, rocker to rocker stud, or rocker to adjustment nut clearance, retainer to valve seal, clearances or rocker geometry, use of the wrong spring load rates for the application,or failure to check valve train or push rods binding issues like rocker to retainer, push rods binding on guide plates or heads,etc. before they became an issue.
about
10% were traced to failure to remove metallic or other trash, generated by a previous cam failing from the engines internal oil passages, or failure to carefully clean the engine before installing the new cam, and components, ( use of shrapnel screens and magnets help a great deal in this but can,t remove all trash as some is non-magnetic)
5% to low quality components, or miss matched parts, like the wrong spring load rates for the application, and perhaps
15% of the failures due to using the wrong lubricants , or not nearly enough moly cam lube on the lobes and lifter bases or setting up the oil supply system correctly, or use of a high quality oil and filter, and a failure to change that oil and filter regularly after the first few hundred miles , the remaining
1o% were from unknown causes but more than likely due to a failure to correctly break in the cam,or properly adjust the valves before the engine break-in process or carefully check and re-adjust the lifters rapidly during the break-in process

GM's RECOMMENDED CRATE ENGINE START-UP PROCEDURE
Print this page out and check off boxes below (in the printed copy) when each step is completed.
Step Box
1) Safety first! If the car is on the ground, be sure the emergency brake is set, the wheels are chocked, and the transmission cannot fall into gear. Next verify that all hoses are tight and that both the radiator and radiator over flow jar/tank are full and have been filled with the proper anti-freeze and water mix.
2) Before starting your engine for the first time, add one pint of engine oil supplement ( EOS¹) to the crankcase oil and then check the oil level. Once this has been done, prime the oil system with an oil pump primer tool. Make sure number 1 cylinder is on TDC compression stroke, and install the distributor.
3) Adjust the distributor timing roughly by hand for a quick start up and smoothest idle possible.
4) When the engine first starts, verify that the engine rpm is at a safe level and that the timing is set near or at 30° before top dead center (BTDC). Run the engine speed between 1,500 and 2,500 RPM’s, varying the engine speed up and down with-in this range, to prevent overheating of the exhaust valves and the exhaust system. This should be done with no-load on the engine and for the first 30 minutes of operation.
5) After the first 30 minutes of the engine running, set the ignition timing according to the timing specifications. Now would be a good time to check thoroughly for leaks.
6) Adjust the carburetor settings, if necessary.
7) Drive the vehicle with varying speeds and loads on the engine for the first 30 miles. Be sure not to use a lot of throttle or high RPM.
8) Run five or six medium-throttle accelerations to about 3,800 RPM (55 to 60 MPH), then letting off in gear and coasting back down to 20 MPH.
9) Run a couple hard-throttle accelerations up to about 3,800 RPM (55 to 60 MPH), then letting off in gear and coasting back down to 20 MPH.
10) Change the oil and filter with recommended oil (10w30SG in most cases) and filter.
11) Drive the next 500 miles normally, without high RPM’s (below 3,800 RPM), hard use, or extended periods of high loading.
12) Change oil and filter again.
13) Your engine is now ready for many happy cruising miles!
Note¹: EOS P/N 1052367 can be used any time during the life of the engine.
Technical Note: This procedure has been corrected and improved from the original GMPP procedure by GILBERT CHEVROLET.
worn10.gif

race-engine-cams.jpg

craneq2.gif


a basic timing chain set like this from cloyes works great in most SBC applications and fits under the stock stamped steel timing cover
https://www.summitracing.com/parts/CLO-9-1100/


SBCOilingnew.png


theres a hugely popular myth that simply is wrong, if your using a dyno simulation software program, ...,
no you don,t reduce or subtract the lift of the cam lobe by the lash, clearance,
when calculating the valve lift of a solid lifter cam,
and you don,t subtract the lifter seat movement on a hydraulic cam,
as that change in lift rate is ALL absorbed or removed on the cam lobes feed ramp
the lifter still lift,s the valve to the full lift
.
measure the difference the edge of the lifter moves from the time the lifter is on the cams base circle to peak lift than set the lifter back on the base circle again and set the dial indicator to zero with a 0.024 feeler gauge between the lifter and dial indicator, and re- measure total lift.
nothing changes on that peak lift , its change is absorbed by the cam lobes feed ramp, the rate of lift per degree of rotation is very slightly delayed , not reduced
heres your typical cam spec card this one happens to be the crane cam I selected for my corvette
crane119661.png


heres the spec card from the t-buckets 406 sbc
crower00471.jpg





graphliftcurve.jpg


lobeliftgraphva.jpg

if you were to graph in the lash slack the valve lift would start a degree or so later and end a degree or so earlier,
but the total lift would remain constant as the distance the lifter travel in the blocks lifter bore as the cam lobe rotates under it,
from the base circle to the peak lift remains consistent



you'll be best served following the manufacturers suggested clearances or (LASH). if your running a solid lifter cam, if they suggest .016 than set them at that, its not critical that they are EXACTLY .016-018,should be fine, but get it as close as you reasonably can.
generally set them on a warm engine , but be 100% sure the valve train geometry and clearances are correct and oil flows from each individual pushrod to each rocker,

http://www.crower.com/media/pdf/2008b/153-155.pdf

http://www.lunatipower.com/Tech/Valvetrain/HowToVerifyValvetrainGeometry.aspx
keep in mind all roller rockers do not have identical dimensions, crower offers .050 off set trunion designs ans the designs dimensions do differ slightly between manufacturers
80-spring_4_549e6142e0344259e9381cdab70222fdb181d8ec.jpg

yes I'm aware a few guys would prefer being skinned alive and dipped in alcohol to reading links!
but for those guys who care to learn more these links might be useful

If your reading this thread and don,t have one, you need one of these tools, ID get one of your old oil filters opened up and inspected,
and ID darn sure be using several magnets to trap loose metallic crud,
is there any chance you or the machine shop, failed to clean the oil pan or block completely and thoroughly?
the metallic debris might be left over debris from the previous engine if the parts used were not correctly cleaned before reassembly!
fillcut1.jpg


fillcut2.jpg


http://garage.grumpysperformance.com/index.php?threads/magnets.120/#post-49771

http://garage.grumpysperformance.co...himmer-in-the-oil-catch-pan.11397/#post-52207

If you have a cam or lifter , or rocker arm , fail, its going to rapidly cause a constant steam of metallic micro trash to enter the oil flowing through the engine, its only a mater of time before that metallic trash causes other moving component wear issues
this is one reason changing oil filters, rather frequently (at least every 7-8K miles)
(IDEALLY the long versions with extra surface area)
and having previously installed several high temp magnets in an engine, you build,
is rather critical too preventing similar damage in any future engine builds

http://garage.grumpysperformance.com/index.php?threads/metallic-debris-in-filter.12364/#post-61283

http://garage.grumpysperformance.co...filters-wix-vs-royal-purple.12988/#post-67560

READ THIS LINK!
http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/



http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/valve-springs.9613/#post-50534

http://garage.grumpysperformance.co...-loads-and-installed-height.10709/#post-46662

http://garage.grumpysperformance.co...u-buy-bare-or-assembled-heads.534/#post-41292

http://garage.grumpysperformance.com/index.php?threads/busted-valve-spring.7716/#post-38047

http://garage.grumpysperformance.co...pring-cooling-via-engine-oil.6491/#post-20681

http://garage.grumpysperformance.com/index.php?threads/vortec-spring-upgrade.6175/#post-19304


http://garage.grumpysperformance.com/index.php?threads/locating-the-source-of-that-noise.15694/

http://garage.grumpysperformance.com/index.php?threads/checking-piston-to-valve-clearances.399/

http://garage.grumpysperformance.co...per-valve-spring-seats-shims.1005/#post-15534

here's a few useful links


http://www.wallaceracing.com/valvelash.htm

https://www.hotrod.com/articles/ctrp-0805-valvetrain-dynamics/

http://www.cranecams.com/?show=faq&id=4

http://www.chevyhiperformance.com/techa ... index.html

http://www.centuryperformance.com/adjus ... g-149.html

http://www.small-block-chevy.com/cb_5.htm

http://www.fordmuscle.com/forums/engine ... tools.html
 
Last edited by a moderator:

grumpyvette

Administrator
Staff member
http://www.american-automobile.com/Erso ... etrain.pdf
yes the cam lobes can very easily contact the connecting rods when the cam index is out of its proper timing, on almost any chevy engine the cam lobe center lines will be spaced at between 103 and 116 degrees, with the piston at TDC theres SUPPOSED to be about .060 MINIMUM clearance between the connecting rod bolts and cam lobes, this is a mandatory clearance check point and a plastic cable tie can be used to gauge clearance, its best done on each individual connecting rod to cam lobe clearance point AFTER the cams been degreed into the block as each connecting rods being installed but Ive generally done it during the several trial assembly points where I check other clearances like block to connecting rod clearance.
if you think about it the cam lobes will pointing basically up in the 180 degrees of rotation and be lifting the valves when the pistons are on the way up the cylinders, and point down toward the crank mostly when the crank throws pulling the rods downward,away from the top of the engine
tappet%20adjustment_zps8vi9yxmu.jpg

theres at least a few hours of very worth while , and quite useful reading in this thread and links that will prevent you wasting time and money, keep in mind the sub links contain a huge wealth of additional info youll need
what seems to be over-looked in many engine builds is simply the fact you'll almost always DEEPLY regret jumping into the engine build with both feet and waving your check book as you sink ever deeper into piles of parts receipts and machine shop bills, rather than stepping back with a legal pad, and a calculator and listing in minute detail exactly what you want to accomplish, and taking the time and effort too list and check out in detail what each machine shop procedure costs, why its required and how much each components costs, what your options are and how each component will add too or benefit the completed combo (or in some cases cause you time and grief)
stepping back and thinking things through in detail and listing the cost and potential problems and finding the solutions BEFORE you dive into the process may be a lot less fun, but in the long term its sure to cost less and result in a far better finished project!

you might be amazed at what a couple hours research into the subject will do to help you build a much more durable engine, and actually reading thru links and sub-links and asking questions helps a great deal

clay5.jpg

almost every mechanics tool box needs a few basic measuring tools and supplies
12cal.jpg

clay6.jpg
https://www.amazon.com/Claytoon-Set...d=1466872286&sr=8-17&keywords=plastilina+clay

http://www.utrechtart.com/Plastalin...currency=USD&gclid=CN3G75zOw80CFQgaaQodKbgFjA


IT helps to know exactly what year and casting number your engine block is as early production big block engines used a different rear cam bearing and cam, a potential rear cam bearing oil flow issue is found on the 1965- too a few very early 1967 engines ,if you install the older design BBC cam with a grooved rear main in EITHER config with EITHER rear bearing your covered, and since thats just not expensive and any decent machine shop can modify any cam like that cheaply is the smart route to take if your in doubt. obviously having the machine shop groove the rear cam journal under the cam bearing in the block like the later BBC engines would be ideal.

camjournal.jpg

1965396CamOilGroovea.jpg

http://garage.grumpysperformance.com/index.php?threads/cam-bearing-install-tools-install-info.1479/



http://garage.grumpysperformance.co...k-after-a-cam-lobe-rod-or-bearings-fail.2919/

http://garage.grumpysperformance.com/index.php?threads/cam-wear-articles-you-need-to-read.282/
scan0001a.gif

pistonatbdc.jpg

pistonat%20tdc.jpg

notice how the rod bolts come close to the cam bearings and cam lobes,as the pistons reach top dead canter in the bores, this clearance must be individually checked and should be no less than about .060 (generally you cam use a LARGE plastic tie-wrap
https://www.amazon.com/BuyCableTies...D=41U9CtmwOuL&preST=_SY300_QL70_&dpSrc=detail
12cal.jpg

41owudXrErL.jpg


placed between the cam lobe and connecting rod bolts or connecting rod shoulder areas to check clearances as the soft tie-wrap will not damage the cam lobe while you verify clearances)

block-clearance.jpg

clearancedrod.jpg


rodcaptocamclearance.JPG

rodcaptoblockclearance.JPG




BaseCircleDiacv.jpg


why you need to verify the cam to rod bolt clearance


rods that use bolts with nuts like pictured below will be weakened if excessively clearance ground
rods that use bolts with nuts like pictured below will be weakened if excessively clearance ground
rod-grinding.jpe

stroker profile rods offer more clearance to cam lobes, and yes the stroker clearanced profile rods are available in both (h) and (I ) beam designs
scatrdx.jpg

hvsiclear1a.jpg


generally its a minor easily done clearance job
camlcc1.jpg

stroker profile rods offer more clearance to cam lobes, and yes the stroker clearanced profile rods are available in both (h) and (I ) beam designs

scatrdx.jpg

on some stroker applications SOME rods need to have the bolts ground for cam lobe clearance
LOOK AT THE TWO REAR CYLINDERS
oilpasse1.jpg

thats why on some stroker crank engines a SMALL BASE CIRCLE cam is used to MAXIMIZE CLEARANCE,between the two moving parts.
a cams lobe lift is the difference the lifter moves off the cams base circle between its base circle and its max lobe lift, thus a cam with a 1.1" diam base circle and a .400 lobe lift would have a , .400 lobe lift and if you had 1.5:1 ratio rockers a .600 valve lift, but if you wanted more clearance you could use a smaller base circle at .900, and a 400 lobe lift this would allow the connecting rod, to sweep by with an additional amount of cam lobe to connecting rod bolt clearance, the change in diameter generally requires a swap to a stronger cam billet core . vs cheaper cast core,to maintain cam strength

removing the rod caps during clearance checks while building your 383 ,does seem to allow you to see the clearance issues a bit easier

rodcaptocamclearance.JPG

rodcaptoblockclearance.JPG

baselobeda.jpg

BaseCircleDiaaaa.jpg

camlcc8.jpg

camlcc9.jpg

camlcc10a.jpg

camlcc9.png

the cam rotates while indexed by the timing chain at 1/2 crank shaft speed , there are connecting rods designed to provide additional clearance.
camlcc1.jpg

camlcc3.jpg

camlcc4.jpg

camlcc5.jpg

camlcc6.jpg

camlcc7.jpg

ERSON MAKES SOME DECENT PARTS
vincam.png

roller rockers have at least potentially the ability to reduce friction in the valve train and free up a few hp, your port flow and cam duration will have a great deal to do with the results you can expect. higher ratio rockers like the 1.6:1 roller rockers most guys buy can effectively add a slight amount of working duration to the valve timing and some additional lift. the problems are usually limited to clearance problems that the higher lift and different rocker geometry can cause
should you use 1.6 ratio roller rockers?

well swapping to roller rockers is always good for a few hp due to reduced friction but it depends on the cams ramp rates and total duration and lift, it can be as much as 7-8 degrees of effective duration or as little as 3-5 degrees, from what Ive seen, keep in mind that 1.6 ratio rockers tend to work much better on mild cams and lower lifts because the total flow change is greater and the stress levels on the valve train is relatively low. once you get over about .550 lift and about 235 at .050 lift and 5000rpm the resulting improvement in flow tends to be less than the resulting stress on the valve train compared to just getting the correct cam with a slight duration and lift increase that is better designed to run above 5000rpm due to the more controlled rate of lifter acceleration which can in a cam originally designed to run 1.5 ratio rockers get to valve float rpm.
look what your trying to do,... what 1.6 rockers are is a nice tuning aid that allows tweaking the cam timing, they are in no way a valid replacement for the correctly matched cam and 1.5 ratio rockers but they ARE an easy way to get a few cfm of extra airflow in the ports IF the ports potentially flow better than the cam your using allows. where I see the best results is in nearly stuck engines where the cam severely restricts airflow at the higher rpms, Ive even seen LOSSES in hp in engine with fairly hot roller cams when 1.6 ratio rockers are added. also sometimes only adding the 1.6 ratio rockers to the intake or exhaust can sometimes gain more than adding the rockers to both
when I was running a crane #114142 cam they helped , when I swapped to a 119661 roller cam they added zero hp over 1.5 ratio rockers in my 383.
http://www.lmengines.com/rocker_arm_changes.htm


http://www.vetteweb.com/tech/0204vet_rockers/



RockerGeometry.jpg

its generally a very good idea to keep all the cam, lifter,valve train and cylinder head components in matched sets, keep components in labeled matched sets, if you intend to reuse used parts in a rebuild. as each wears in, or laps in to its matched components a bit differently thus random assembly increases the chances of future parts
failures
dualspring.jpg


https://www.summitracing.com/search?SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=POW735002

valvetraya3.jpg

valvetraya4.jpg

read these links
http://www.superchevy.com/how-to/engines-drivetrain/sucp-0202-rocker-arm-ratio/


http://www.hotrod.com/articles/ctrp-0703-rocker-arm-comparison/

http://www.hotrod.com/articles/roller-rocker-ratio-test/
rocker003vb4.jpg


rocker003vb1.gif

rocker003vb2.jpg


rlcf1.jpg

rlcf2.jpg

rlcf3.jpg

trashinbearing5.jpg



keep in mind all that metallic trash, cycles through the oil pump BEFORE it reaches the oil filter


Crower has developed a new rocker arm to cure many ailments, including the one we ran into. By relocating the hole in the rocker trunion (left), Crower eliminated the problem of pushrods hitting the heads. This also moves the rocker away from the retainer and can correct the problems associated with using longer valves and rotated valve angles.
anytime your not sure about something, or theres a defective link, ASK, don,t assume.
I try too keep current but theres always going to be people changing the linked info on different linked sights
either product pictured below works on head bolt or rocker stud threads, simply dip the threads and screw into place
80057.jpg

80063.jpg


rockerstudp1t.jpg

check all valve train geometry and clearance on any engine you assemble or modify the valve train on.
bbcvtq5.jpg


read the threads

http://garage.grumpysperformance.co...venting-leaky-head-bolts-studs.50/#post-12558

http://garage.grumpysperformance.com/index.php?threads/sealants-and-threads.805/#post-45066

http://garage.grumpysperformance.com/index.php?threads/parts-prep-cleaning.6255/#post-19681

http://garage.grumpysperformance.com/index.php?threads/torque-to-yeild-head-bolts.2138/#post-5763

http://garage.grumpysperformance.com/index.php?threads/wrong-rocker.13987/#post-71250

http://garage.grumpysperformance.co...s-in-vs-threaded-rocker-studs.2746/#post-7475

a standard chevy sbc cam will not rotate randomly and freely and clear the connecting rods,
in a 383 engine, if its not properly timed with a timing chain in place to force the cam being indexed correctly, so cam lobes, are indexed to avoid hitting the connecting rod bolt shoulder area,
,you need to correctly degree the cam in...BUT EVEN THEN,
.in some cases a small base circle cam must be used to clear some connecting rods in a 383.with its 3.75" stroke, remember the original 265/283 SBC has a 3" stroke
.
block-clearance.jpg


plastigty5.jpg

clearancedrod.jpg


rodcaptocamclearance.JPG

rodcaptoblockclearance.JPG



BaseCircleDiacv.jpg

read ALL the linked info carefully and then ask questions
http://garage.grumpysperformance.com/index.php?threads/cam-degreeing.9010/#post-35474
http://garage.grumpysperformance.co...ing-a-383-sbc-combo-planing.12168/#post-71932
http://garage.grumpysperformance.com/index.php?threads/small-base-circle-cams.3810/#post-72512
http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/
http://garage.grumpysperformance.com/index.php?threads/383-information-overload.11137/
http://garage.grumpysperformance.com/index.php?threads/bits-of-383-info.38/#post-7680
http://garage.grumpysperformance.co...gine-to-match-the-cam-specs.11764/#post-55571

Last edited: 2 minutes ago




sguide_plate.jpg

pushrodbind.jpg


REMEMBER TO CAREFULLY CHECK THE PUSH ROD TOO CYLINDER HEAD GUIDE SLOT AND CYLINDER HEAD CASTING CLEARANCES,IF THE PUSH ROD BINDS IT MAY CAUSE A LOSS OF OIL FLOW THROUGH THE PUSH ROD, FROM LIFTER TOO ROCKER OR THE LIFTER TO WEAR RAPIDLY

checking all valve train clearance issues in mandatory
MikeB said:
.....

CLEAR-01.jpg


viewtopic.php?f=52&t=181
Grumpy -- man, those are some big clearance numbers!

maybe so but its what most of the cam and valve train component manufacturers suggest using, and since they spend hundreds of thousand$ on research, and have done YEARS OF RESEARCH AND TESTING, I tend to go with their experience.
now Ive only built a few hundred engines in the last 45 years but so far it seems to be good advice


youll also want to verify piston to valve clearances and correct quench

valclear2a.jpg

vcl1.jpg

vcl2.jpg

p173610.jpg

PTVC_05.jpg

vgd4.jpg

keep in mind that the intake valve usually starts to open well before the piston reaches TDC on its exhaust stroke, and continues to extend out towards the piston after it passes TDC and follows it down into the bore as it descends on the intake stroke, generally closest contact points are in the 20 degrees btdc too 20 degrees atdc, obviously exact potential clearances are dependent on both cam timing and cam indexing
http://www.sallee-chevrolet.com/Proform/rocker_arm_pics.html

http://www.cranecams.com/master/goldrace.htm

http://www.compcams.com/information/Products/RockerArms/ProMagnum.asp

https://www.trickflow.com/search/department/camshafts-valvetrain

http://www.fl-thirdgen.org/rockerswap.html

http://garage.grumpysperformance.com/index.php?threads/finding-matched-valve-spring-required.13774/

heres a simple way to get close to the correct length
BUY ONE OF THESE
66042132.jpg

400-200-PushrodDiagramA.jpg

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=3567&prmenbr=361

after making sure the valve springs are correctly installed you drop the checker in place on the rocker stud and install your adjustable push rod
adjust the length to fit and measure the resulting length if its within twenty thousands of the stock length its fine for most applications, if its more than 30 thousands long or short get the closest length set available

btw, if your one of the people that still does not own an adjustable push rod! you can easily make your own by cutting a stock push rod in 1/2 (2 pieces), removing 1 inch from the total length an then with about 2 " of a 4 inch section of 3/16 or 1/4" thread rod installed and (in one section epoxy it in place leaving about 2" sticking out thread two nuts onto the thread rod and slip on the other end of the cut push rod,(no epoxy) use the two nuts to adjust to stock length and let the epoxy hardened in the one section[/color] now you can easily measure and order custom push rods using the push rod checker and adjustable push rod as tools
AND YEAH IT ONLY WORKS WITH THE CYLINDER HEADS ON AND THE INTAKE REMOVED BECAUSE THE HOLE IN THE CYLINDER HEAD that Guides THE PUSH ROD WON,T ALLOW THE NUTS ON THE ADJUSTABLE PUSH ROD TO PASS THRU, UNLESS YOU PLACE THE CUT ABOUT 1" from the UPPER END OF THE ADJUSTABLE TEST PUSH ROD BUT I prefer to place the adjusting nuts centered as I like to watch for all clearances with the intake manifold removed while manually checking as I turn the engine over by hand durring assembly, and at that point, while checking all the clearances, I use test springs which apply very little load on the push rod
8928864.jpg


http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=3272&prmenbr=361

HERES OTHER TOOLS YOU MIGHT NEED
http://www.summitracing.com/parts/pro-66830
66830.jpg



77866784.jpg


77866902.jpg


24947101.jpg


71062391.jpg


SOMETHING TO READ
http://www.compcams.com/information/Products/Pushrods/

CCA-7705 5.800 in. to 9.800 in. adjustment range, Master pushrod length checker 4 piece kit ... $78.69

here

hppp_0902_15_z+comp_cams+valve_spring_diagram.jpg


self aligning rockers have ridges to prevent the rocker from moving off the valve stem
COC1318-1.jpg


p177897_image_large.jpg

0607phr_31_z+camshaft_basics+valve_springs.jpg


pushrodbind.jpg


cyl7.jpg


RockerArmPivotInstall_2521.jpg


pictured above you see the last rocked badly out of alignment with the valve center line,
a good example why you need adjustable guide plates, this rocker if left too run off center like this, on the valve stem tip , will quickly destroy the valve guide and rocker
sbcadj.jpg


small block chevy adjustable push rod guide plate
301-27001230-4.jpg

BBC ADJUSTABLE PUSH ROD GUIDE PLATE


its rather common to have push rods rub or bind when swapping to the higher ratio 1.6:1 rockers so its mandatory you carefully check EVERY one through its full arc for proper clearance and use a louis tool to extend the push rod guide holes is thats required
this is mostly a matter of carefully checking clearances and verifying valve train
geometry,and use of quality parts rather than selecting the cheapest crap available, in many cases the simple swap of components can be done with few issues ,BUT its rather common for parts too bolt in, but not fit correctly, but LESS-experienced mechanics don,t see the indications of potential trouble,and wonder why parts failed later as a result!
parts that rub or bind and were thought too be correctly functioning only to be found later too be causing rapid wear or even a cam or lifter failure as a result of the parts installer, NOT verifying the correct clearances and geometry, so take your time and read the links and check, never assume a darn thing, fits correctly until you verify the clearances over the full range of movement.
read thru the links and sub links they may open your eyes
Ive used lash caps to protect valve stem tips on lots of engines , but Id pint out that you really need to verify several things before you use them, obviously the first point is you have the required length of valve stem tip extending above the retainer and the correct valve lash cap design to fit your particular application.
but be aware theres several different designs and sizes available and valve spring retainer and rocker arm designs vary a great deal, making checking clearances and geometry through the full arc the rocker moves mandatory
12cal.jpg

http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/#post-54232

retain6.jpg

look through this thread
http://garage.grumpysperformance.com/index.php?threads/two-loose-valve-locks.9687/#post-47884

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/


youll want too use a .060 clearance too the push rod to cylinder head slot clearance CHECKED CAREFULLY OVER THE FULL ARC OF THE ROCKER TRAVEL FOR A FULL TWO ENGINE ROTATIONS
if you need a LOUIS TOOL to lengthen the slots in the cylinder head I generally lay a section of plastic wrap in the lifter gallery and be sure to place two magnets on the blocks lifter gallery wall, to hold the thin plastic wrap in place firmly, below the cylinder head while drilling to catch the metalic debris the drill will generally produce, between the plastic sheat and the magnets youll generally catch 100% of the trash the drill generates

24947101.jpg


STUD-12.jpg

louis2.png

louis1.png

http://www.magnet4less.com/product_info.php?cPath=3_27&products_id=254
magnetpic.jpg

or
http://www.magnet4sale.com/samarium-cobalt-discs/


obviously having adjustable push rod guide plates to center the rockers on the valve stems and push rods in the cylinder head slots is almost mandatory.
as is verifying all rocker geometry and valve train clearance issues
prctool.png

http://www.summitracing.com/search/...d-length-checkers?autoview=SKU&ibanner=SREPD5
Proform Pushrod Length Checkers 66789 SBC 3/8" rocker studs

Proform Pushrod Length Checkers 66790 SBC 7/16" rocker studs

Proform Pushrod Length Checkers 66806 BBC 7/16" rocker studs
Ive occasionally been asked what you can do too reduce the slack in the timing chain if your blocks been line honed,
to straiten the main bearings and that resulted in a slightly closer crank to cam center-line distance,
that results in a slightly increased slack in the stock timing chain sets.
a negligible amount of metal is generally removed from the main bearing saddles in the block, they usually try very hard to minimize that, metal removal so standard parts still fit,during a line hone , but they do sell slightly tighter timing chain sets to correct excess slack if that's required.
SBCprintCustom2.jpg



cloyesunder.jpg


https://www.summitracing.com/parts/clo-9-3100-5
Timing Chain and Gear Set, Original True Roller, Double Roller, -0.005 in., Iron/Steel Sprockets, Chevy, Small Block, Set
for line honed blocks where the crank is .005 closer to the cam


https://www.summitracing.com/parts/clo-9-3100-10
for line honed blocks where the crank is .010 closer to the cam
Timing Chain and Gear Set, Original True Roller, Double Roller, -0.010 in., Iron/Steel Sprockets, Chevy, Small Block, Set

viewtopic.php?f=52&t=126&hilit=louis+tool

http://garage.grumpysperformance.com/index.php?threads/upgrade-choices.11416/#post-52423

viewtopic.php?f=52&t=528&p=45493&hilit=+long+slot#p45493


http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/#post-54088

http://garage.grumpysperformance.co...-rockers-and-the-pushrods-rub.198/#post-46839

http://garage.grumpysperformance.co...all-block-chevy-guide-plates.2839/#post-12739

http://garage.grumpysperformance.co...-rockers-and-the-pushrods-rub.198/#post-46839

notice the approximate location and relationship between the cam pin and crank key

http://www.superchevy.com/technical/eng ... index.html
sucp_0609_06_z+chevy_small_block+timing_gear_and_chain.jpg

obviously if the engine locks up at some point in the rotation, while you test to find out why the engine won't easily rotate a full 360 degrees,
but allows you too reverse directions and spin it almost the full 360 degrees before it again locks, preventing full rotation your engines got some part physically binding, preventing your rotation, , its most likely sone failed part like a broken piston, or valve train component, forcing it will result in DAMAGE, thus you must pull the head(S) and maybe the oil pan for a closer inspection, before you proceed and potentially cause more damage
 

Attachments

  • ValveSpringClearance01.jpg
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grumpyvette

Administrator
Staff member
once you've installed a new cam in your engine its necessary to determine the correct valve train geometry, this is MANDATORY if you want the cam to function correctly.
yes the stock length may work just fine! but you must check!
http://www.racingsprings.com/PDF/Design ... v%2001.pdf


if you don,t think use of the correct valve springs and rockers matters heres the dyno results on a 496 BBC chevy engine with a new set of valve springs and roller rockers, obviously if correctly selected,they can make a difference
betvspa.jpg


Valve Spring Tech
Valve Spring Pocket Clearance
Valve spring pocket clearance is the gap between the inside diameter of the valve spring pocket (or cup, if used) and the outside diameter of the valve spring.

  • Too much clearance will result in the spring "dancing" around in the head, which "beats up" the spring mounting surface and the spring itself. If this is the case, a spring cup may be used. Additional machining of the spring pocket may be required to accept the spring cup.
  • Not enough clearance will bind the spring in the pocket, overstressing the bottom coil by limiting its movement and not allowing the spring to "grow". This will cause the bottom coil to wear against the head and/or prematurely fail. Machine the valve pocket using a Spring Seat Cutter if not enough clearance exists.
ValveSpringDetail.gif

Valve Spring Retainer Fit
The valve spring retainer should fit the valve spring being used. A slightly snug fit is acceptable, however a fit that is too tight can overstress the top coil, and cause it to fail. A fit that is too loose can lead to spring "dancing."

Valve Spring Installed Height
The installed height of the valve spring is the distance between the valve pocket (or cup, or shims) and the outer edge of the spring retainer (which is the height of the valve spring) when the valve is closed. To check installed height, follow the following procedure:

  1. Install the valve in the guide.
  2. Install the retainer and valve locks.
  3. Install all spring cups and/or valve spring shims (basically, everything except the valve spring).
  4. Hold the valve closed by pulling the retainer up tightly against the valve locks.
  5. Measure the distance between the outside edge of the valve spring retainer and the spring seat. A snap gage or a height micrometer should be used.
  6. Check the distance against what is recommended on the camshaft specification card. An installed height of +/- 0.020" is acceptable.
  7. If the installed height is not within 0.020", either machining of the valve pocket, or removal/installation of valve spring shims is necessary.
  8. Repeat this procedure for the rest of the valves.
ValveSpringClearance.gif

Valve Spring Retainer to Valve Seal Clearance
The distance between the innermost step on the valve spring retainer and the valve guide must be 0.090" larger than the maximum valve lift of the camshaft. Measure the distance between the top of the valve seal to the bottom of the valve spring retainer. After adding 0.090" to your measurement, it should still be larger than the maximum valve lift of the camshaft. If not, machining of the valve guide in necessary for adequate clearance.

Valve Spring Coil Clearance
Coil clearance is the distance between the valve spring coils when the valve is it maximum lift (fully open). A minimum of 0.060" must exist between the coils at maximum lift. Coil bind is when the valve spring is compressed fully-to the point that all of the coils are "stacked up" on top of each other. For high RPM applications, .100" is recommended . Coil bind is a catastrophic condition that will result in valve train failure. Disassemble each spring (if multiple springs are employed at each valve). Check all the springs (both inner, and outer springs) If there is not 0.060" - 0.100" minimum of clearance between the coils, the solutions are: the valve retainer, the valve locks, the valve, or the spring must be changed; the spring pocket must be machined. Keep in mind that these modifications will change the valve spring installed height

ValveSpringRockerClearance.gif

Valve Spring Retainer to Rocker Arm Clearance
When installing the rocker arms, check to see that the inside of the rocker arms clear the spring retainers. Many rocker arms have a "relief" to accommodate large valve spring retainers.

Valve Spring Run-In
Each set of Lunati valve springs are hand-selected to keep load variations below +/- 10% of the next. However, it is important to "run in" your new valve springs at low RPM using the following procedure:

  1. Start the engine and run the engine between 1500 and 2000 RPM until the engine reaches operating temperature.
  2. Shut off the engine and allow the springs to cool.
  3. After initial run-in, most springs will lose a slight amount of pressure. Re-check and shim up the valve springs if necessary. After the springs are "run in", spring pressure should remain constant until the point of replacement.
Impala65SS said:
...

Assuming the pushrods been installed with guide plates, there will be slight wear only visible, not tactile, from rubbing against the guide plates, that is quite normal.

Invest in an adjustable pushrod, and a push rod length checking tool before you decide to buy any pushrods! Your head has been "done over", so the factory valve train geometry HAS been ever so slightly changed.
pushrodbn.jpg

rlcf1.jpg

rlcf2.jpg

rlcf3.jpg

yeah, it takes a bit of work and a few accurate tools, but you don,t need to do much compared to tearing the engine totally appart to expose the cam, you can meassure lift and duration accurately at a valve retainer or even more accurately with the rockers removed at a push rod tip
pro-66830_cp.jpg

pro-66791.jpg

checklifter3.jpg


dialinc2.jpg

dialinc1.jpg

a simple dial indicator fixture, on a push rod tip after removing the rockers from the Number 1 cylinder, and a degree wheel on the crank hub,and a piece of graph paper and your time to graph out the lift vs degree of rotation, would give accurate info, that is going to be a whole lot less work and gives you FACTS VS guessing at the answer

http://www.harborfreight.com/multipositional-magnetic-base-with-fine-adjustment-5645.html
17902z.jpg


18512z.jpg

http://www.harborfreight.com/1-inch-travel-machinists-dial-indicator-623.html

http://www.igagingstore.com/MAGNETIC-BASE-FLEXIBLE-FLEX-ARM-001-DIAL-INDICAT-p/203957.htm
flexmagb.png

flexmagba.jpg

http://garage.grumpysperformance.co...hing-the-drive-train-to-the-engine-combo.741/

http://garage.grumpysperformance.co...electing-a-torque-converter-stall-speed.1715/

http://garage.grumpysperformance.co...late-gear-ratios-and-when-to-shift-calcs.555/
I buy most of my replacement valve springs from these guys
http://www.racingsprings.com/
(866) 799-9417
http://www.racingsprings.com/Staff
heres their ph#
Toll Free (866) 799-9417
I always just order the springs retainers valve locks and spring seats as a package deal (NOT CHEAP BUT EVERYTHING WORKS AND FITS) then you just need shims under the valve spring seats occasionally to get the correct installed height


http://www.summitracing.com/parts/sum-900013/overview/

http://www.summitracing.com/parts/sum-900012/overview/

SUM-900012_xla.jpg

btvalve.png


springt1.jpg

springt2.jpg

springt3.jpg

springt4.jpg

springt5.jpg

springt6.jpg

springt7.jpg



PRO-66776_xl.jpg


http://www.buxtonengineering.com/on_head_valve_spring_tester.php

http://www.racingsprings.com/1300-Series-/1300-Series-/sku/33

http://www.racingsprings.com/1500-series/sku/34

good quality valve springs are fairly expensive, youll generally pay $250-$450 for decent valve springs and many guys start looking for far cheaper imported sets, that are of lower quality, at bargain prices, the problem is that you generally find a set, and comparing the price it makes it hard for some guys to remember YOU GENERALLY GET WHAT YOU PAY FOR AND THERE'S A DARN GOOD REASON THE IMPORTED PARTS ARE CHEAPER

all it takes is a tiny bit of research and some math to calculate the ideal rear differential gearing, tires size etc. and transmission gear ratios, and you can certainly select the correct torque converter stall speed if you have a dyno graph of your engines power curve without much difficulty, an hour or so spent in reading and research will provide you with a great deal better performance from most cars.
and a couple days worth of research and doing some math on all of the power trains component parts will provide you with a wealth of info that can prevent you from making costly mistakes.

HERES A FEW OF THE OILS I TRUST, coat flat tappet lifters and cam lobes with crane moly assembly paste lube
crn-99004-1_w.jpg

I usually use 6-7 quarts of oil and 1 quart of marvel mystery oil added in my oil pan 11 quart oil pan and oil cooler system capacity

10W30 Valvoline VR1 Conventional Racing Oil
10W30 Valvoline NSL
10w30 Castrol GTX conventional,
10w30 mobile 1
10w30 KENDAL racing oil

zddp.jpg

and heres a good break in additive for flat tappet lifter cams
http://www.summitracing.com/parts/CRO-86092
http://www.acdelco.com/auto-parts/v...engine-oil-supplement-assembly-lubricant.html
eos.png


related threads

http://garage.grumpysperformance.co...-the-rabbit-hole-with-alice.10933/#post-66925

http://garage.grumpysperformance.co...et-it-to-last-cam-install-info.90/#post-57942


http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-57678

http://garage.grumpysperformance.co...ng-cam-and-shifting-the-lca.10553/#post-44949

http://garage.grumpysperformance.com/index.php?threads/cam-degreeing.9010/#post-35474

http://garage.grumpysperformance.com/index.php?threads/identify-that-cam.8582/#post-30180

http://garage.grumpysperformance.co...op-dead-center-1-for-timing-ignition-cam.966/
http://garage.grumpysperformance.com/index.php?threads/turning-your-crank-manually.5933/


start by setting the degree wheel on the crank hub at
Top Dead Center for cylinder #1
and personally Id remove the rockers and meassure from the push rod tip and use a piston stop to verify tdc

http://www.wallaceracing.com/Calculators.htm

youll be amazed at the amount of detailed info in threads and sub links Ive put together to help you gentlemen

http://garage.grumpysperformance.com/index.php?threads/the-trucks-just-not-running-well.13435/

The right length pushrod will yeild the right valve stem wear pattern - in the middle of the valve stem. This is particularly important if you ever want to try longer ratio rockers, as the wear pattern on the stem will be wider, i.e. closer to the valve stem edges.
TIPS-23bn.jpg

80-spring_3_bcfea434c54b3193a82c9dd8f87b5de3bbddc33e.jpg


You can get lash caps to get more wiggle room, less wear on the valve stem too.
lashcapbn.jpg

read this thread also

viewtopic.php?f=32&t=1000

heres a quick way described below
auto0075kn.jpg


https://www.summitracing.com/parts/pro-66485
louist.jpg

These Proform pushrod slotting tools are designed to elongate the pushrod slot in the cylinder head. They will make room for higher ratio rocker arms. Use these tools with a drill and a 5/16 in. drill bit to elongate the pushrod slot.
pro-66485_w.jpg


sucp_0202_03_z+engine_parts_pushrods+diagram.jpg

correct length..................too short............................too long

" to QUOTE MOTORMAN.....
you just put the lifter on the cam base circle,slip the checker over the stud,if the checker hits the valve first use a feeler gauge between the checker and the push rod tip to see how much longer push rod you need. if the checker hits the pushover first use a feeler gauge to check the gap at the valve stem tip and that is the amount you need to shorten the push rod"

its not that difficult to figure out, read these links also

http://www.compcams.com/information/Products/Pushrods/

http://www.powerandperformancenews.com/s...=LENGTHCHECKERS

http://www.cylinderheadsupply.com/valve-guide-tools-guide-top-cutters.html

yes you need to check.
heres a simple way to get close to the correct length
BUY ONE OF THESE
66042132.jpg

400-200-PushrodDiagramA.jpg

http://www.jegs.com/cgi-bin/ncommerce3/ProductDisplay?prrfnbr=3567&prmenbr=361

https://www.centuryperformance.com/...ure.html?xid=lzE72fc7xSMfhyuSoWOoereKbqSCEK7w

after making sure the valve springs are correctly installed (correct height, and you've checked for spring bind,retainer to valve guide, retainer to rocker,rocker to rocker stud,and push rod to cylinder head slot clearance ETC, you drop the correct style push rod checker in place on the rocker stud and install your adjustable push rod
adjust the length to fit and measure the resulting length if its within twenty thousands of the stock length its fine for most applications, if its more than 30 thousands long or short get the closest length set available
be aware the push rod checkers come in 3/8" and 7/16" stud models, and bbc and sbc models

http://www.superchevy.com/how-to/engines-drivetrain/sucp-0202-rocker-arm-ratio/

http://www.compcams.com/Products/CC-%27 ... %27-0.aspx

btw
http://www.powerandperformancenews.com/s...;Category_Code=

BEEHIVE DESIGN springs , with the upper side being smaller in diam. and using a smaller retainer,
300-300_26120.jpg


available from several manufactures similar too these give much greater clearance to the rocker/retainer area and tend to control valve float harmonics if you find that your current springs won,t work

0508ch_how_08_z.jpg


the push rod length checker is used after the stock rockers removed like in this picture, simply rotate the engine to TDC on the rotation where BOTH valves are SHUT, remember there's a 720 degree repetitive cycle, #1 fires on one rotation at TDC and #6 fires on the next rotation, you measure when both valves are closed at TDC and read the links again,
BTW they make check gauges for 7/16" and 3/8" studs get the one matching your engine size
auto0075kn.jpg

Specialty Auto Parts U.S.A.,
Proper push rod length is absolutely critical
for peak performance—minimizing bent or
broken valve stems, guide wear, and ener
gy-wasting valve side-loading friction.
With the lifter located on the round base
circle, position the Push Rod length Checker
(make sure you have the Checker with the prope
r diameter hole) over the stud. Ideally the
Checker should contact the top of the push
rod and the valve tip evenly at the same
moment, should the Checker contact the push ro
d first, measure the gap between the front
of the checker and the valve tip, and purchas
e a shorter push rod of
the correct length.
Should the Checker contact the valve tip first,
measure the gap between the back of the
Checker and the top of the push r
od, and purchase a longer push rod.
Specialty Auto Parts U.S.A Inc

http://www.summitracing.com/parts/pro-66789/overview/
KEEP IN MIND THE PICTURE at SUMMIT IS UPSIDE DOWN

http://www.summitracing.com/parts/cca-7901-1/overview/

http://www.summitracing.com/parts/cca-7901-1/overview/
CCA-7901-1_VV_xl.jpg

youll need these also
adjustablepush.jpg
adjustablepush1.jpg
adjustablepush2.jpg

in an ideal valve train geometry set-up the sweep mark on the valve tip will be very narrow and close to the valve center-line , but having the sweep mark narrow is more important than keeping it centered on the valve stem tip, the valve train does not like lateral or side ways loads on the valves and the wider sweep is an indicator of that issue, while a correctly set up valve train may have components that result in the valve tip sweep mark being slightly off the valve center-line this is not a major concern.
Its checking and verifying the valve train clearances and basic geometry that should be your major concern

the clearances and rocker geometry (push rod length,spring bind rocker to rocker stud clearance, etc.) must be checked carefully prior to starting the engine,and adding the magnets to trap metallic debris sure helps.
in every case Ive seen, in the past,
where a cam and lifter failed during the break-in process,
over the last 45 years,
careful inspection showed some component in the valve train was binding,
clearances or geometry was not correct , the valves were adjusted improperly, or the proper moly paste and lubricants were not used.
and Id point out that some lifters and cam cores sold by some manufacturers do tend to be more suceptable as I suspect they are noticeably softer materials


I use mostly
CRANE
LUNATI
ERSON
CROWER
and ocasionally
ISKY



comp-cams-solid-flat-tappet-liftersa.jpg

notice RHOADS LIFTERS have an OPTIONAL oil groove,feature of similar design, but due to the requirement for fast and easy manufacturing they also extend the groove upward from the oil passage band so it will squirt oil up out of the lifter bores into the lifter gallery where it does little good, rather than just to the cam & lifter interface area where it does help cool and lubricate the area under stress.
rhoadssu.png

the better quality hydraulic and solid flat tappet lifters have hardened bases
hardface.jpg

btw the best deal I found lately on basic hydraulic flat tappet lifters
http://www.summitracing.com/parts/sum-ht817/overview/


lobelif.png


SOME ROLLER ROCKERS CAN AND DO BIND ON ROCKER STUDS, or rocker adjustment nuts, youll need to check carefully
rpo1x.JPG

some roller rocker too retainer combo clearance issues cause problems easily solved with beehive springs and smaller retainer diameters

beehivesprcl.jpg


the POLY LOCKS that are used with most roller rockers AND ROLLER ROCKER SIZES, (come in a variety of lengths AND DIAMETERS AND THREAD SIZES) so you might find you need tall valve covers to allow clearance BUT in most cases swapping to shorter poly locks reduced that problem from mandating taller valve covers, be aware that the outside diameter of the locks is a darn important factor in allowing the rocker to reach full potential lift!
it should be obvious that youll need to carefully check clearances over the full rotation and lift in several areas if you chance valve train components and retainer to rocker and internal rocker clearance slot to poly lock are two of many potential places the valve train may bind if theres not the correct clearance

rockerh1.png

rockerh2.png


rockerbin.jpg

rockertrunion1.png



rockflr2.jpg

rockflr1.jpg

worn1.jpg

the brand or part number won,t mater much if the valve train binds during the arc, the cam lobe will wear and the rocker will eventually fail under the stress.

SELF ALIGNING ROCKERS (BELOW)
USED WITH PRESS IN ROCKER STUDS
rockersGP002.jpg


used with press in rocker studs

pressedstud.jpg

rockersGP009.jpg

yes they DO MAKE ROLLER ROCKERS IN BOTH STANDARD AND SELF ALIGNING VERSIONS

stampedcvrockersa.jpg

the grooved rocker pivot ball design was an effort by G.M. engineering to economically solve the issue of marginal oil flow causing rocker ball galling, and resulting noisy, or broken valve trains


rockeroilfeed.jpg


rockstcl.jpg



check all valve train geometry and clearance on any engine you assemble or modify the valve train on.
bbcvtq5.jpg



bbcrk1.jpg


rockeroilfeed.jpg

longslot.jpg


if your heads have push rod guide plates you are not supposed to use self aligning rockers as yes they will frequently bind the push rods up and keep them from spinning, if you have guide plates you want the NON-self aligning rockers
as I've pointed out dozens of times a day spent reading links will save you a week of work and a wheelbarrow full of wasted cash.

most good brand name aluminum or steel roller rockers have pressed in hardened steel push rod seats that are far less likely to wear than the tips of the push rods.
cranerrco.jpg

OBVIOUSLY that assumes you have no valve train clearance issues, binding or geometry or lubrication issues, and you set the lash or lifter pre-load on the valve train correctly and use the correct oil, and it certainly would help any engines durability to have provisions for adequate valve train oiling and a bit extra valve train cooling can be helpful on an engine designed for higher rpm use.verify rocker body and trunion clearance at ALL points in the rockers arc. VERY CAREFULLY

THIS STUFF WORKS
crn-99004.jpg

cambreakin.jpg

drawsdf.jpg


http://car-diesel-oil.blogspot.com/2015/06/best-motor-oil-car-oil-lab-test-for_63.html?view=sidebar
The Moly platelets that make up the protective layers on your engine surfaces slide across one another very easily. Instead of metal rubbing against metal, you have Moly platelets moving across one another protecting and lubricating the metal engine parts.

This coating effectively fills in the microscopic pores that cover the surface of all engine parts, making them smoother. This feature is important in providing an effective seal on the combustion chamber. By filling in the craters and pores Moly improves this seal allowing for more efficient combustion and engine performance.
nosqueeze.jpeg

This overlapping coating of Moly also gives protection against loading (perpendicular) forces. These forces occur on the bearings, and lifters. The high pressures that occur between these moving parts tend to squeeze normal lubricants out.
valve springs must be installed at a specific semi compressed and listed installed height,
to provide the listed load rates and clearances,
example

crane110921.jpg

the cam you select will generally come with a suggested listed valve spring load rate and installed height,
(NOTICE THE SUGGESTED INSTALLED HEIGHT WITH THIS CAM IS 1.800"
and the loads are listed)

you must maintain minimum coil bind and retainer to valve seal clearance and proper push-rod and rocker geometry
the distance between the lower edge of the valve spring retainer and the cylinder head is adjustable to achieve the desired valve spring height through the use of valve spring seat cups and shims placed under the valve spring which can be purchased to lock into a stock height, or plus or minus about .050, and valve locks that cam move the retainer (stock or aftermarket) an additional .050 either tighter or longer allowing the valve spring to expand taller, shims can be placed under the valve seat hardened cups that are almost always mandatory on aluminum head but may be optional on iron heads,(O.E.M. cast iron and lower valve spring load rates)

ValveSpringDetail.gif


clear.jpg




valvespringinstalled.gif


springshima.jpg

prctool.png


retain6.jpg


bbcspring2.gif

installedheight.gif




edvalvs.jpg

valvespringseats.png

Installedsp.jpg

valvespringseatsx.png

max lift is installed height minus .060 minus coil bind
drawsdf.jpg

related info you really need to read
http://garage.grumpysperformance.co...ring-installation-questions.12833/#post-66460

http://garage.grumpysperformance.co...-loads-and-installed-height.10709/#post-46658

http://garage.grumpysperformance.co...ve-spring-iinstalled-height.12791/#post-66038

http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-57678

http://garage.grumpysperformance.com/index.php?threads/valve-springs.9613/#post-50556

changing the oil filter after an hour or so of run time, and use of several magnets in the engine will reduce the potential for trash in the oil
installedheight.gif

selfalighningrockertx.jpg

RELATED

http://www.hotrod.com/articles/ctrp-0611-rocker-arm-valvetrain-geometry/

http://www.enginelabs.com/engine-te...ing-valvetrain-geometry-and-getting-it-right/

http://www.lunatipower.com/Tech/Valvetrain/HowToVerifyValvetrainGeometry.aspx

http://www.sbintl.com/tech_library/articles/rocker_arm_geometry.pdf


http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/magnets.120/#post-49772

http://garage.grumpysperformance.co...ear-articles-you-need-to-read.282/#post-52017


http://garage.grumpysperformance.co...lifter-to-increase-oil-flow.11152/#post-49968

http://garage.grumpysperformance.com/index.php?threads/breaking-in-a-new-engine-combo.799/#post-1161

http://garage.grumpysperformance.co...ilter-you-sellect-does-make-a-differance.117/

http://garage.grumpysperformance.co...oil-passages-and-improved-oil-flow-mods.3834/

http://garage.grumpysperformance.co...rally-bad-ideas-concerning-oil-control.10388/

http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/#post-37266


4KU76_AS01.JPG


BTW DON,T assume that the intake and exhaust push rods are the same length, yeah they usually are on a SBC engine but there are exceptions....CAREFULLY CHECK SEVERAL or ALL CYLINDERS
especially if your using aftermarket heads and roller rockers
Ive used lash caps to protect valve stem tips on lots of engines , but Id pint out that you really need to verify several things before you use them, obviously the first point is you have the required length of valve stem tip extending above the retainer and the correct valve lash cap design to fit your particular application.
but be aware theres several different designs and sizes available and valve spring retainer and rocker arm designs vary a great deal, making checking clearances and geometry through the full arc the rocker moves mandatory
12cal.jpg


heres a bit of useful related push rod length info
Big Block Chevy, Standard Length Big Block Intake 3/8" / .080" 8.275"
295-7941-8 Big Block Chevy, Standard Length Big Block Exhaust 3/8" / .080" 9.250"
295-7969-8 Big Block Chevy, Standard Big Block +.100" Long Intake 3/8" / .080" 8.375"
295-7979-8 Big Block Chevy, Standard Big Block +.100" Long Exhaust 3/8" / .080" 9.350"
295-7951-8 Big Block Chevy, Standard Length Big Block Tall Deck Intake 3/8" / .080" 8.675"
295-7961-8 Big Block Chevy, Standard Length Big Block Tall Deck Exhaust 3/8" / .080" 9.650"
295-7800 V8 396-454 Retro Fit Pushrod Set, Intake & Exhaust, 1965-Present
3/8" / .080"
3/8" / .080" 7.725 Int.
8.675 Exh
295-7913-16 Small Block Chevy, Standard Length Small Block Chevy 3/8" / .080" 7.800"
295-7984-16 Small Block Chevy, +.100" Long 3/8" / .080" 7.900"
295-7934-16 Big Block Ford, Standard Length Ford `72-'78 429-460 3/8" / .080" 8.550"
295-7951-16 Big Block Ford, Standard Length Ford `69-'71 429-460 3/8" / .080" 8.675"
295-7582-16 Oldsmobile, Std Length 455 5/16" 9.550"
http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/#post-54232
springyu1.jpg

springyu2.jpg

springyu3.jpg

springyu4.jpg

springyu5.jpg

retain6.jpg

the reduced diameter of beehive valve springs usually eliminates the rocker too retainer clearance issue

springseatk.jpg


beespryj.jpg


read THESE links

http://garage.grumpysperformance.com/index.php?threads/timing-chains-stretch.5734/#post-17492


http://garage.grumpysperformance.co...hanics-of-adv-ret-a-camshaft.4532/#post-67562

http://garage.grumpysperformance.co...et-it-to-last-cam-install-info.90/#post-57942

http://garage.grumpysperformance.co...nter-1-for-timing-ignition-cam.966/#post-1682

http://garage.grumpysperformance.co...e-train-clearances-and-problems.528/#post-668

http://garage.grumpysperformance.co...king-piston-to-valve-clearances.399/#post-488

http://www.competitionproducts.com/Camshaft-Degreeing-and-Cam-Measuring-Tools/products/1387/

http://garage.grumpysperformance.com/index.php?threads/two-loose-valve-locks.9687/#post-47884

http://garage.grumpysperformance.com/index.php?threads/sellecting-valve-springs-and-setting-up-the-valve-train.181

until you take the time to verify
your just guessing
checking your clearances and testing, verifying if everything,
is properly fitted and the geometry is correct is just not that difficult.


http://garage.grumpysperformance.co...oven-facts-if-your-in-doubt.13051/#post-69824

http://garage.grumpysperformance.co...hink-logically-don-t-assume.12484/#post-62772

http://garage.grumpysperformance.com/index.php?threads/diagnoseing-tpi-lt1-problems.1241/#post-2648

http://garage.grumpysperformance.com/index.php?threads/locating-vacume-leaks.882/#post-45944

just be sure you verify all clearances
(piston to valve,
rocker to rocker stud,
rocker to retainers, etc. )
I think you made a good choice from what I see posted so far
Id install it strait up, IE no advance split overlap_






http://garage.grumpysperformance.com/index.php?threads/how-to-read-a-cam-spec-card.1477/


yeah lots of info/reading but it potentially prevents several issues


http://garage.grumpysperformance.co...ng-cam-and-shifting-the-lca.10553/#post-44949

http://garage.grumpysperformance.com/index.php?threads/cam-degreeing.9010/#post-35474

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-12997

http://garage.grumpysperformance.co...hanics-of-adv-ret-a-camshaft.4532/#post-12050

http://garage.grumpysperformance.com/index.php?threads/degreeing-in-a-cam-correctly.3097/#post-8240

http://garage.grumpysperformance.com/index.php?threads/cam-degree-equipment-tools.1759/#post-4440

http://garage.grumpysperformance.co...rect-custom-length-pushrods.14241/#post-72355
 
Last edited by a moderator:

grumpyvette

Administrator
Staff member
get the ignition timing as close as you can, but use a timing light as soon as you can to verify the ignition timing, if its off significantly the engine can run into detonation or the headers can get extremely hot.
letting it idle is not always necessary , you can just set the timing at 34-36 degees at 3100 rpm and wait untill its got the cam lapped in, but if youve got the correct molly cam lube, E.O.S. in the oil, plenty of oil pressure and all your clearances are correct, and plenty of oil in the engine,a brief time at idles not likely to cause problems in my experiance, its been over 28 years since IVE seen a cam lobe problem at break-in, and then it was a clearance issue not procedure.
ID bet the vast majority of cam problems can be traced too clearance or geometry issues or lack of moly assembly lube and E.O.S. and failure to provide lots of oil flow, not failing to keep the rpms over 2500rpm for the first 1/2 hour
 

grumpyvette

Administrator
Staff member
occasionally you'll have an application where you'll want to use roller rockers and short valve covers and find theres a clearance issue,its usually NOT the rockers as much as the taller JAM NUTS, or drip tabs inside the rocker covers causing the clearance issues , roller rockers don,t require the same volume of oil so drip tabs can be cut out with no durability issues if you use roller rockers, but the interior slot length and width of the roller rocker slot the jam nuts fit into in many cases are so small and restrictive that you can,t use any thing but a jam nut with the hex located well above the rocker to lock the rocker in place

its the attention to details and checking clearance etc. and time and care taken,
that makes the difference between a barely or average functional ,
and a rather exceptional engine build, yes the urge to get it running is strong,
but getting it done correctly is the goal
some time spent reading related links about your potential valve train issues could prevent lots of potential problems
http://garage.grumpysperformance.co...-pushrods-and-check-info-you-might-need.5931/
http://garage.grumpysperformance.co...rect-custom-length-pushrods.14241/#post-72353
http://garage.grumpysperformance.co...-rockers-and-the-pushrods-rub.198/#post-46839
http://garage.grumpysperformance.com/index.php?threads/press-in-vs-threaded-rocker-studs.2746/
http://garage.grumpysperformance.co...s-tool-swapping-to-1-6-1-ratio-rockers.14761/
http://garage.grumpysperformance.co...rdering-correct-custom-length-pushrods.14241/
http://garage.grumpysperformance.co...ange-in-valve-spring-iinstalled-height.12791/
http://garage.grumpysperformance.co...1-6-1-ratio-rockers-and-the-pushrods-rub.198/

yodam.jpg

ultrapro.jpg

rockernut.jpg

there are some jam nuts that are slightly shorter in length
arp-300-8245_w.jpg

RockerArmPivotInstall_2521.jpg


viewtopic.php?f=52&t=6186&p=19333&hilit=rocker+roller+flat#p19333

BTW, I occasionally find I'm working with some guys who either lack experience or are clueless as to their options, when bolting an intake manifold down on an engine.
Ive watched guys fight for 20 minutes trying to tighten the standard 9/16" hex head machine bolts on some intakes where access was very limited

Coarse-Thread Socket-Head Bolts - 3/8in.-16 (thread) x 1 1/4inch (length).

most guys are familiar with use of standard HEX HEAD BOLTS
36RG04_AS02.jpg

when used on a chevy aluminum intake manifold you'll frequently find, the required room,for easy access with a box or open end wrench is very limited due to the intake runner proximity to the threaded holes center line,
and that after some time standard bolt heads tend to rust and dis-color aluminum intakes.

now ideally youll use a lock washer, under the bolt head and ANTI SEIZE on the bolt threads
lockwas.jpg

that prevents vibration and heat cycles from allowing the bolts to back out of the threaded holes.
there are both 6 and 12 point, reduced bolt head size , stainless bolt sets available that allow increased clearance

intablt1.jpg

intablt2.jpg


capscrew1n.jpg


STAINLESS STEEL socket head cap screws make a much neater look ,
are less likely to rust,and allow far more clearance around the bolt heads, both standard and TORX versions and several head designs are available
BUTTON HEAD VERSIONS MAKE FOR A CLEAN APPEARANCE


1CET2_AS01.jpg

.
Valve spring replacement schedule ???

Id suggest that both the rate or speed of the lobe ramp design and the amount of valve spring pressure will affect the potential expected life span of the valve springs
it should be rather obvious that the quality of valve springs varies with manufacturers
it is recommended to check ALL spring pressures once a year or every 15K miles.
That does not mean they will need replacing,
that is proper maintenance. Depending on the lobes used and if properly installed, certain springs can last 30+k, some less some more.

personally I have always suggested testing every 15 k miles or about once every once a year,
and
if you find any valve springs that have lost more than about 10%- 12% of the originally listed seat or compressed load rate its time to replace the set.
most of us can,t justify purchaseing a valve spring test tool,
but most better machine shops will test them ,

if you drop them off in a box with the listed installed height, max lift and seat pressure listed for under $40-$50 for a set, in my experience

A VALVE SPRING LOAD TESTER IS EXPENSIVE, BUT A GREAT TOOL TO HAVE
vsts1.jpg

http://streetperformanceusa.com/i-72754 ... ester.html
vsts2a.jpg

http://www.summitracing.com/parts/pro-66775
vsts3.jpg

http://www.summitracing.com/parts/pro-66776/overview/
https://www.compcams.com/valve-springs-101

https://www.hotrod.com/articles/hrdp-1011-what-you-need-to-know-about-valvesprings/

https://www.enginebuildermag.com/2010/01/performance-valve-springs-and-retainers/

https://www.nhra.com/news/2019/how-pick-valve-springs-your-race-car

https://www.aa1car.com/library/valve_spring_diagnosis.htm


http://garage.grumpysperformance.com/index.php?threads/busted-valve-spring.7716/#post-38047

http://garage.grumpysperformance.co...t-compressed-when-installed.11356/#post-51869


I have roughly 15,000 miles over 5 years on the original Brodix valve springs. Is it all about the number of cycles or does time have to be factored into this equation? How often should they be changed when the lift is .560 inches. I sure don't want to drop a valve, it would NOT be worth a set of new valve springs.

Should I see more valve rotation ???
(I would not be overly worried, most valves rotate slowly during operation)

Most valves in an operating small engine rotate about the valve stem axis at varying rates. Valve rotation has an overall positive effect on valve life. Rotation provides improved temperature distribution in the valve head and a mild scraping action that cleans the valve interface of any crushed combustion deposits.
Each time a valve opens, the valve rotator turns the valve slightly. This prevents the valves sticking due to carbon build up. Additionally, it allows the inlet and exhaust valves to be heated and cooled symmetrically. ... Cleaner valves reduce engine emissions and prevent burning and guttering of the valve face and seat.

Looking at the witness marks on the valve tips, it sure does not look like the valves are rotating. On some intake valves I've noticed that the valve stems (close the valve head) is polished. I thought about taking some photos, but just didn't think I could capture the details.

Does the protrusion of the rocker stud hole into the intake port disrupt flow ???
I was wondering how much this hole disturbs the flow thru the intake port. Have there been any dyno tests? It would be easy to fill with some JB Weld to make the intake port wall continuous.

TW, remember to visually verify the stud length and cut them a bit shorter if required you don,t want the lower end protruding into the intake port and any threads doing that do NOTHING to increase the stud rigidity but they sure can reduce port flow rates if left sticking down into the air flow path
rockerstudp1t.jpg

rockerstudp2.jpg


ID ALSO POINT OUT THAT A ROCKER STUD GIRDLE ADDS A GOOD DEAL MORE STABILITY TO THE VALVE TRAIN
if the stud extends into the port ID get it machined shorter
if the lower rocker stud does not reach into the port Id be more concerned,
with the potential need to add a rocker stud girdle for rigidity than with minor port flow irregularity
p
IMG_2071.jpg

http://www.summitracing.com/parts/SUM-141010/?rtype=10
sum-141010.jpg

http://www.summitracing.com/parts/CCA-4014/
caa-4014.jpg

wrl-832010_w.jpg


viewtopic.php?f=52&t=1769

Photo0020.jpg
 
Last edited by a moderator:

grumpyvette

Administrator
Staff member
ALLEN said:
grumpy, Ive bent another push rod and I carefully verified I don,t have any piston to valve interference (its .120 on the intakes and .140 on the exhaust)or coil bind issues , any ideas?

the most common fault I see is guys who fail to verify the clearances in the valve train that may not be obvious like the rocker slot to rocker stud clearance, or retainer to valve guide, clearance, or the edge of the valve to the valve pocket in the piston. most guys check for coil bind and push rod length, and use some clay to verify the valve face to piston clearance but few guys that I see come to my shop seem to have verified all the potential issues like push rod to push rod guide plate clearance over the full sweep of the rocker travel.
use of a camshaft install handle generally reduces the chances of damaged cam bearings

CCA-4919_xla.jpg

cca-4919_w.jpg

preventing cam & lifter break-in failures
I can easily see why you might be confused, if you read enough internet commando posts you'll very quickly get the idea that hydraulic roller lifters will last a great deal longer than solid roller lifters. (thats frequently the case mostly because solid roller lifters are run with much higher valve spring load rates and spun up to much higher rpms thus operate under much higher stress, if both types of valve trains were run under similar stress and rpm limitations both styles would have similar life expectancy)
but what the vast majority of the posters fail to mention is that the valve spring load rates and peak rpm expectations , plus the basic cam core materials, and valve train quality, all can vary a great deal, and in general, the solid roller lifters are generally lighter in mass(weight) so that they can and will operate safely to slightly higher rpms with identical valve spring load rates, compared to the heavier hydraulic roller lifters, but remember you'll need to match the valve spring load rates too the intended inertial loads the valve train will be expected to see, during its intended operational rpm band.
if you run an engines rpms up to the point the lifters loft, of FLOAT, ( or leave the cam lobe surface due to inertial loads exceeding the valve springs ability to maintain lifter to cam lobe contact, valve train damage will usually quickly follow)
your generally going to see stock O.E.M. valve springs start to not be able to control hydraulic rollers at about 6000 rpm, and remember valve springs have a tendency to loose the load rates as the stress and age of the valve spring in use is extended, so a new set of O.E.M. valve springs that controlled the valve train very effectively for the first 10K-20K miles will no longer have anything like the original resistance or load rates after 20K miles in most cases.
any time your building a new engine youll want to talk to several engineers at several cam manufacturers to discuss, carefully matching...
the cam and valve train components youll want to use and the limitations of the parts you'll select, discuss the cams intended operational rpm range the cars weight, drive train and rear gear, tire size, basic lobe lift, duration, lobe separation, engine displacement and compression, along with the valve spring load rates lifter design, rocker ratio, and the potential use of a billet or hardened cam core.
P1-CHARTS.jpg

related info

The following recommendations are from Erson Cams. If you have questions, you can reach their tech department at 800-641-7920.

Hydraulic Flat Tappet Camshaft: 110 lbs Seat pressure/250-280 lbs open pressure

Solid Flat Tappet Camshaft: 130 lbs Seat Pressure/300-325 lbs open pressure

Hydraulic Roller Camshaft: 130-140 lbs Seat Pressure/300- 355 lbs open pressure

Solid Roller Camshaft: (Minimum Safe Pressures DEPEND ON SEVERAL FACTORS)

Up to .600Ë valve lift: 200-235 lbs Seat Pressure/600 lbs open pressure

Over .600Ë valve lift: 250-280 lbs Seat pressure /100 lbs pressure for every .100Ë of valve lift



http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.co...-the-extra-cost-vs-a-flat-tappet-design.3802/

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/rod-bolts-rpm-vs-stress.341/#post-30778

http://garage.grumpysperformance.com/index.php?threads/redline.343/#post-58215

http://garage.grumpysperformance.com/index.php?threads/what-springs.11352/#post-51835

http://garage.grumpysperformance.co...ulic-roller-lifter-selection.5522/#post-16620

http://garage.grumpysperformance.co...ng-pressures-don-t-work-well.1489/#post-16234

http://garage.grumpysperformance.co...rect-valve-spring-load-rates.4680/#post-12650

http://garage.grumpysperformance.com/index.php?threads/small-base-circle-cams.3810/#post-10118


it should be rather obvious that there's options,you'll chose in both valve train components and lubricants, cam failures are usually the result of incorrect CLEARANCES or too much SPRING PRESSURE or LACK of ADEQUATE LUBRICATION,USE DECENT MOLY CAM LUBE, and decent quality oil, adding MAGNETS to trap metallic CRUD HELPS, if your not getting constant oil flow from each rocker /push rod at idle theres something wrong and that needs to be checked
vincam.png

marvel.jpg

plewsoilm.jpg

http://www.plews-edelmann.com/oil-cans-and-oilers/
pre-oiling the rockers before starting an engine the first time helps prevent problems


longslot.jpg

bbcspring2.gif

BE aware you need to verify rocker adjustment lock nut to rocker slot clearance and yes it varies even with the same manufacturers different rocker designs
rockerh1.png


rocknut.png

rockerh2.png

rockerbin.jpg

PtV3.jpg

03313a.jpg

GRAPH SHOWING VALVE AND PISTON LOCATION, ,USUALLY AT ITS CLOSEST BETWEEN 10-20 DEGREES BFTDC and USUALLY AT ITS CLOSEST BETWEEN 10-20 DEGREES AFTDC

http://www.cylinderheadsupply.com/valve-guide-tools-guide-top-cutters.html

http://garage.grumpysperformance.com/index.php?threads/leak-down-test.332/#post-14272

http://garage.grumpysperformance.com/index.php?threads/oil-on-plugs.11044/#post-49058





YES TAKING THE TIME TO READ SUB LINKS IS WELL WORTH THE EFFORT

http://www.enginebuildermag.com/2011/01 ... cker-arms/

http://www.hi-flow.com/HP012dVT.html

viewtopic.php?f=54&t=120&p=28636#p28636

http://static.summitracing.com/global/i ... 411-16.pdf

viewtopic.php?f=52&t=6641&p=21035#p21035

viewtopic.php?f=52&t=399

http://static.summitracing.com/global/i ... 82%291.pdf




http://garage.grumpysperformance.com/index.php?threads/valve-seat-runout.15104/#post-86003

http://garage.grumpysperformance.co...u-buy-bare-or-assembled-heads.534/#post-81754


http://garage.grumpysperformance.com/index.php?threads/multi-angle-valve-job-related.3143/

http://garage.grumpysperformance.co...gree-valve-seats-tpi-motors.14662/#post-98674

http://garage.grumpysperformance.co...gree-valve-seats-tpi-motors.14662/#post-98674

http://garage.grumpysperformance.com/index.php?threads/ccing-my-heads.14187/#post-71989

http://garage.grumpysperformance.co...olishing-combustion-chambers.2630/#post-48319

http://garage.grumpysperformance.co...at-angles-and-air-flow.8460/page-2#post-33298

http://garage.grumpysperformance.com/index.php?threads/removing-valve-seals.4283/#post-11290

http://garage.grumpysperformance.com/index.php?threads/sellecting-cylinder-heads.796/

http://garage.grumpysperformance.co...and-setting-up-the-valve-train.181/#post-1397

Stainless Valves: Do you really need them?

I thought this was interesting info from the Isky website. I can't find where I have SS valves, but a magnet will NOT stick to one of the Brodix IK200 valves. I'm wondering if I should consider buying valve lash caps??? http://www.iskycams.com/techinfo_index.html Click on "Tech Tips 2000"...
garage.grumpysperformance.com

don,t forget to use proper valve spring seats/shims

now you may not need these, on all applications, but aluminum heads can be damaged if the valve spring is run directly on the head surface ,and if the springs base can move around due to harmonics at high rpms it can cause valve control issues and wear issues and they are a good idea on even...
garage.grumpysperformance.com

sellecting valve springs, and setting up the valve train

How do you determine the spring pressure needed to keep the valves under control for a given lift, duration, and max rpm. It might take you several hours to read thru all the links and sub links but its time very well spent as it could save your engine from destruction and save you thousands of...
garage.grumpysperformance.com



CRANE CAMS said:
Besides Coil Bind, What Other Types of Mechanical Interference Should You Look Out For?
When you increase the valve lift with a bigger cam or increased rocker arm ratio you must be sure that there is no interference between any of the moving parts. Some of the components that must be inspected for clearance are:

1. The distance from the bottom of the valve spring retainer and the top of the valve stem guide, or the top of the valve stem seal must be equal to the net valve lift of the valve plus at least .060" more for clearance.

2. When using rocker arms mounted on a stud, the length of the slot in the rocker arm body must be inspected to be sure it is long enough to avoid binding on the stud. The ends of the slot must be at least .060" away from the stud when the rocker is at full valve lift and when the valve is closed. ? Crane Cams offers steel long slot and extra long slot rocker arms to relieve this interference problem. Aluminum roller rocker arms may be required to provide sufficient travel on larger lift camshafts.

3. The underside of the rocker arm body cannot touch the valve spring retainer. You will need at least .040" clearance to the retainer throughout the full movement of the rocker arm. If necessary, a different shape retainer or rocker arm design will be required. In some cases, installing a lash cap on the tip of the valve stem can provide the clearance required.

4. Valve to piston clearance must be checked to be sure there is sufficient clearance. The intake valve must have at least .100" clearance to the piston and at least .120" clearance on the exhaust valve.
 
Last edited by a moderator:

grumpyvette

Administrator
Staff member
tthorp32 said:
I have a 383 stroker that has 10.5:1 compression with trick flow twisted wedge g1 heads. The max lift I can use from a cam before the valves hit a piston is .520 if I use different springs. "So long as you stay at or below 236* @ .050" Duration, No less than a 108* LSA, you can go up to about .520" lift before piston to valve clearance becomes an issue." I need help on cam selection. I want a hydraulic roller cam. It's a non roller block. I'm trying to make around 500 horsepower. It's a street strip setup with a t56 transmission. Also 1.52:1 rocker arms. Thanks in advance!
any time you find the valve train producing a noise its generally a clearance issue or a worn part,
to help locate the source of the noise, take off the valve cover and, have a buddy start the engine,
press down on the rockers individually at idle with the palm of your hand,
,if the lifter, rocker or other valvetrain component is worn or mal-adjusted,
the sound on each valve assembly will change as pressures applied to the rocker with the heal of your hand on the rocker testing individually at idle,
obviously done before oil temps rise too far and
visually check for cracked valve springs,
bent or loose rocker studs and
rocker slots that contact the rocker stud

and
missing valve lock keys in the valve spring retainer
Id also suggest you swap rockers if you find one causing the noise,
burn or worn rocker balls in the rocker can cause this,
and that helps you isolate the defective component

https://www.chevydiy.com/small-block-chevy-rocker-arms-studs-pushrods-lifters-guide/

6-4.jpg


Stamped rockers use a slot cut in the base of the rocker that allows the rocker to move relative to the stud. With higher lift cams, make sure there is a minimum of 0.050 inches clearance between the end of the rocker slot and the rocker stud at max lift.


2-4.jpg




13-3.jpg


In the mid 1980s, all production small blocks began using “guided” rocker arms that use two small guides that straddle the valve tip to locate the rocker arm tip. Guided or “rail” rockers should not be used with guideplates since this could create a binding situation that would break parts.
its not unusual to find mixed sets on older engines:mad:



let us know what you find:rolleyes::p

http://garage.grumpysperformance.co...-engine-noise-valve-train-or-rod-knock.13846/

http://garage.grumpysperformance.co...ectly-and-get-it-to-last-cam-install-info.90/

http://garage.grumpysperformance.com/index.php?threads/small-base-circle-cams.3810/

http://garage.grumpysperformance.co...ifter-for-checking-cam-timing.3745/#post-9950

http://garage.grumpysperformance.com/index.php?threads/degreeing-in-a-cam-correctly.3097/#post-8240

http://garage.grumpysperformance.com/index.php?threads/cam-degree-equipment-tools.1759/#post-4440

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-12997

http://garage.grumpysperformance.com/index.php?threads/what-causes-valve-float.11502/#post-52997



cambreakin.jpg

62191_ATA.jpg

scan10001B.gif

SUM-G1056_xl.jpg

cambutclear.jpg

http://garage.grumpysperformance.com/index.php?threads/how-to-pick-timing-gear-set.4548/#post-43700

http://garage.grumpysperformance.com/index.php?threads/timing-chains.2209/#post-32459

http://garage.grumpysperformance.com/index.php?threads/timing-chains-stretch.5734/#post-17492

http://garage.grumpysperformance.com/index.php?threads/cam-spacer-buttons.1793/#post-4553

http://garage.grumpysperformance.co...ear-articles-you-need-to-read.282/#post-57371


SPRAYING ALL VALVE TRAIN COMPONENTS DURING ASSEMBLY WITH MOLY REDUCES FRICTION
molysp3.JPG

molysp2.JPG

molysp1.JPG

pre-spraying all bearing and valve train components with a moly based spray, helps embed micro moly lubricants in the metallic surface micro fissures , a good paste lube like cranes assembly lube over the spray surface helps insure a good lubricant surface coating, that is far stronger than just the ZINC and PHOSPHATES in oil
crn-99004.jpg


What valve springs would go good with this? Will any beehive springs fit those heads?
first ID point out that those are the guide lines that came with those heads and
THEY DON,T ALWAYS APPLY, you NEED TO ACTUALLY MEASURE YOUR PISTON TO VALVE CLEARANCE AND VALVE TRAIN CLEARANCES
you will be taking a HUGE gamble if you don,t VERIFY your TRUE clearances, and ID also point out that the valve springs can be and should be UPGRADED for use with a roller cam as the load rates are different, plus the fact that your valve springs and seals are at least 15 years old now, because they stopped selling those heads at least that long ago.
they are decent heads if in good condition but need better springs for a hydraulic roller cam.
It would help to know more about the car weight, rear gear, headers etc, and if you need to pass emission testing.
check the valve seals and valve guides for wear, as the G1 heads have a reputation for wearing originally installed valve guides

retain6.jpg

the reduced diameter of beehive valve springs usually eliminates the rocker too retainer clearance issue
011-bbc-big-block-chevy-nitrous-comp-cams-hydraulic-roller.jpg

this is what is SUGGESTED BY most cam manufacturers



viewtopic.php?f=52&t=3293&p=8709&hilit=twisted+wedge#p8709

viewtopic.php?f=52&t=181

viewtopic.php?f=52&t=399
viewtopic.php?f=52&t=399&p=488#p488

I don,t know many or in fact any engine builder that doesn,t have some good model clay in his tool box for checking clearances
wd40.jpg

or a can of wd 40 to spray on the valves and clay too prevent clay sticking to parts measured, use good quality modeling clay, some crap like kids PLAY DOUGH, is SPRINGY and won,t give exact and consistent measurements, I pick mine up at a local arts & craft supply

clay6.jpg

116_0701_06_z+valve_to_piston_clearnace+indentations.jpg


116_0701_04_z+valve_to_piston_clearnace+measure.jpg



when you select a hydraulic roller cam from any major manufacturer like crane or crower they will suggest a matching valve spring kit.generally hydraulic roller cams require a bit heavier load rates as the lifters are heavier and impart more inertial loads on the valve train, mandating the stronger springs use to maintain the lifter to cam lobe contact as rpms increase, this usually but not always involves minor machine work or at least a change on the valve shims and retainers, but frequently youll need to swap to different valve seals. so check with the manufacturer and be sure to ask lots of questions so you don,t assume you can just stuff a new cam in and have it work, because in most cases not following the guidelines voids the warranty and prevents the cam from functioning as nits designed too.
Hydraulic Roller Camshaft:generally use, 130-140 lbs Seat Pressure/300- 355 lbs open pressure
If your confused by the terms, lets try this, using this cam and the spring it lists

crane110921.jpg

once installed the valve spring max length is the installed height,
ValveSpringDetail.gif

max lift is installed height minus .060 minus coil bind
drawsdf.jpg


if you used these valve springs
Crane Cams#271-99846-16
Single Valve Springs
Outside Diameter: 1.255"
Inside Diameter: .870
Seat Pressure: 125 LBS @ 1.800"
Open Pressure: 383 LBS @ 1.200
Coil Bind: 1.100"
Rate (LBS/IN.): 428
Max Lift: .640
Set of 16
coil bind is 1.100 so minus .060 from the installed height of 1.800, you get 1.160 lift,subtracted from 1.800 (.640 clearance) but the valve only forces the spring to compress to max valve lift which will be less than the .640 max lift, while the installed height of 1.800 minus the max permissible lift with that spring 1.800-1.160= .640 in this case the cam lobe lift on the lifter multiplied by the rocker ratio provides a .536 max spring compression, since you have a max usable lift clearance of .640 available with that spring at that installed height,in this case, the .536 lift the cam lobe provides,compresses the valve spring about .104 less than the max permissible lift so clearance will be fine and the valve lift will never reach the full theoretical valve spring compression or load rate listed, it will with the stated load rate of 428 lbs per inch of compression see a lower rate than the listed 383 lbs as .536 lift x 428 lbs per inch of compression= roughly 230 lbs

BTW Im sure the question would come up about swapping to a 1.6:1 ratio rocker, how will that effect the result above?
cams are listed with the stock in this case (SBC) 1.5:1 rocker ratio, in the case above that provides a .536 lift on the exhaust lobe which is a bit more than the listed .518 on the intake,valve, if we were to swap from the stock 1.5:1 ratio to a 1.6:1 ratio you simply divide that listed .536 by 15 then multiply by 16 and you'll find you'll see a change to a .571 lift, still under the .640 max lift
never use both push rod guides and self aligning rockers

youll be far ahead if you carefully read the linked and sub-linked info



http://garage.grumpysperformance.com/index.php?threads/wrong-rocker.13987/#post-71250

http://garage.grumpysperformance.co...rect-custom-length-pushrods.14241/#post-72346

http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-57678

http://garage.grumpysperformance.co...engine-and-bent-two-pushrods.4712/#post-56192

http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/#post-54088

http://garage.grumpysperformance.co...-in-vs-threaded-rocker-studs.2746/#post-43539

http://garage.grumpysperformance.co...-rockers-and-the-pushrods-rub.198/#post-46839

http://garage.grumpysperformance.co...nd-check-info-you-might-need.5931/#post-18267

http://garage.grumpysperformance.co...all-block-chevy-guide-plates.2839/#post-12739
related info
viewtopic.php?f=52&t=181

viewtopic.php?f=52&t=3802

viewtopic.php?f=52&t=1376

viewtopic.php?f=52&t=2746

viewtopic.php?f=52&t=5522

viewtopic.php?f=52&t=9392
 

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    ValveSpringClearance01.jpg
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Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
ALLEN said:
how close will a regular DOT-TO-DOT cam install get your average cam to its intended correct install, location?

you might want to read this threads and sub links, and short answer, its generally close enough to function but its frequently costing you 3-15 hp over a correctly indexed cam, correctly degreed in. (but I've seen cases of imported timing sets that were a good deal further off)

worth watching, just for the tips on new head inspection
http://garage.grumpysperformance.co...ectly-and-get-it-to-last-cam-install-info.90/

http://garage.grumpysperformance.com/index.php?threads/how-to-pick-timing-gear-set.4548/#post-43700

http://garage.grumpysperformance.com/index.php?threads/cam-degree-equipment-tools.1759/#post-4435

http://garage.grumpysperformance.com/index.php?threads/checking-piston-to-valve-clearances.399/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

both offset retainers and offset valve locks exist that will each allow .050 added height,or clearance, but be aware added space reduces the valve spring pressure

http://garage.grumpysperformance.co...ng-height-load-on-a-l98-383.14592/#post-77688

http://garage.grumpysperformance.co...tched-valve-spring-required.13774/#post-77425

http://garage.grumpysperformance.com/index.php?threads/what-springs.11352/#post-51835

http://garage.grumpysperformance.co...-loads-and-installed-height.10709/#post-46658

http://garage.grumpysperformance.com/index.php?threads/valve-guide-cutting.8382/#post-29239


http://garage.grumpysperformance.co...d-high-spring-pressures-don-t-work-well.1489/

http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-79273
 
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Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
OK lets go into the problem,and info on potential solutions
(the failed cam lobe to lifter contact and rapid unacceptable wear area)
theres several routes or areas of concern, to look into
Proper clearances,
proper valve train geometry,
lubrication,
cooling,
protection from, and containment of metallic debris, generated through wear.

before, you start reading through the thread and links below, Ill point out that I,ve done the forensics on quite a few failed cams over the years that guys have brought to my shop and
Id say about
60%
of the failed cam lobe & lifter problems were traced to a failure to check clearances or correct valve train geometry issues , like coil bind, rocker to rocker stud, or rocker to adjustment nut clearance, retainer to valve seal, clearances or rocker geometry, use of the wrong spring load rates for the application,or failure to check valve train or push rods binding issues like rocker to retainer, push rods binding on guide plates or heads,etc.before they became an issue.
about
10% were traced to failure to remove metallic or other trash, generated by a previous cam failing from the engines internal oil passages, or failure to carefully clean the engine before installing the new cam, and components, ( use of shrapnel screens and magnets help a great deal in this but can,t remove all trash as some is non-magnetic)
5%
to low quality components, or miss matched parts, like the wrong spring load rates for the application, and perhaps
15% of the failures due to using the wrong lubricants , or not nearly enough moly cam lube on the lobes and lifter bases or setting up the oil supply system correctly, or use of a high quality oil and filter, and a failure to change that oil and filter regularly after the first few hundred miles , the remaining
1o% were from unknown causes but more than likely due to a failure to correctly break in the cam,or properly adjust the valves before the engine break-in process or carefully check and re-adjust the lifters rapidly during the break-in process
its likely cause



once the engines solidly supported in the car frame and properly connected,
to its sub support electrical,exhaust and cooling systems theres no reason NOT,
to fire it up and check for correct function, look for oil leaks,
break in the rings, set the ignition timing,set the carb floats,verify oil flows liberally from all rockers, check fuel pressure, and check the valve train and do the valve adjustments and initial tuning!

plewsoilm.jpg

the plews 50-347 I bought last year at that auto parts store, is still working fine so for the $15 I paid its been worth the price

https://www.tooltopia.com/plews_lubrimatic-50-347.aspx

https://www.newegg.com/Product/Product.aspx?Item=0MG-0023-00016

OH! in case your curious
I own TWO now , I bought a second one several month later, too use for cutting oil when I use the MILLING MACHINE or DRILL PRESS

http://www.amazon.com/CRC-SL2512-Solubl ... r+drilling
41YtvD98P5L.jpg

you might think of having the engine installed like that as a rudimentary,
engine test stand

YOU'LL MISS A GREAT DEAL OF INFO,
IF YOU SKIP READING LINKS AND SUB_LINKS ,SCATTERED THROUGH MOST THREADS

related info

http://garage.grumpysperformance.com/index.php?threads/limited-oil-choices-for-cam-break-in.13602/


http://garage.grumpysperformance.com/index.php?threads/engine-test-run-stand.930/#post-40783

http://garage.grumpysperformance.co...ear-articles-you-need-to-read.282/#post-52016

http://garage.grumpysperformance.com/index.php?threads/cam-break-in-procedure.130/#post-160

Cam Break-in Procedure
cambreakin.jpg

crn-99004.jpg

MOLY adds a great deal of lubrication to sliding metal surfaces , as it embeds in the micro fissures in the metallic surface's

• Have a high quality service manual available, such as the factory service manual, or the vehicle specific manuals published by Chiltons, Motors, or Haynes. You will need these for the basic information regarding engine disassemble and reassemble along with the torque settings for the various fasteners.

• Read and understand the manual completely, along with these instructions before you begin working. We highly recommend you also have the assistance of a knowledgeable friend to assist you, especially during the initial fire-up and break-in period.

In addition to the normal installation procedure, installing a performance camshaft requires you to check for several extra items to insure long life and optimum performance.

• New Lifters Are A Must- There is no such thing as a good used lifter! Any flat faced lifter establishes a wear pattern almost immediately with the cam lobe it is riding on and cannot be used on any other cam lobe, let alone a different cam. Should you have a need to disassemble the engine, make sure you keep the lifters in order so they go back on to the exact same lobes.

• Valve Spring Pressure and Travel- We highly recommend purchasing the matching valve springs recommended in our catalog. This insures you will have the proper pressures, both closed and open, and sufficient travel to get the maximum rpm, performance and life from your new cam.

• Piston to Valve Clearance- While many performance cams will work just fine with stock pistons, there are many factors that effect your engine and the clearance available. Things such as factory tolerances, normal machine work such as head and block surfacing, aftermarket components such as cylinder heads, higher ratio rocker arms, etc. all effect your engines ability to handle a performance camshaft.

• Valve Train Interference- In addition to valve spring travel and piston-to-valve clearance, a commonly overlooked area is that of retainer to seal clearance. The other common area of interference is rocker arm to stud clearance along with rocker arm travel. The best way to check these is by physically opening both a intake and an exhaust valve on each cylinder head to the gross lift of the cam plus and additional .030". It is easiest to do this by pressing down on the rocker arm with one of the many tools available. Do not simply rotate the engine to the maximum lift point for a given valve. This does not work when engines are hydraulic lifter equipped, or even allow any margin of safety when you are using a mechanical lifter cam.

• Valve Adjustment- The easiest way to insure proper adjustment is to adjust the rocker arms as you install them, one cylinder at a time. Adjust the intake valve as the exhaust valve is just starting to open and adjust the exhaust valve when the intake valve is almost closed. It is simplest to do this with the intake manifold off and watching the lifter’s movement.

• Hydraulic Lifter Valve Adjustment- All engines, regardless of manufacture, require correct valve adjustment. Some engines, such as Chevrolet V-8’s, are equipped with stud mounted rocker arms can easily be adjusted to compensate for changes incurred during engine assembly. Never just torque the rocker arm into place and assume that the lifter preload will automatically be correct. Various engine manufacturers use multiple length pushrods, shims, and spacers to compensate for changes in preload. Hydraulic lifters cannot compensate for all changes. Ideal lifter preload is .020" to .080". Do not attempt to fill the lifters full of oil prior to installation. They will fill automatically once started and manually filling them makes adjusting the preload a difficult task.

• Mechanical Lifter Valve Adjustment- Adjusting mechanical lifters should be done the same way as outlined above, one valve at a time. For an initial setting, we recommend .003" to .005" than listed on the cam’s specification card. Once broken in and with the engine fully warmed up, re set the rocker arms to the cam’s specification sheet.

• Installation Lubricants- All flat faced (non-roller) camshafts require the use of high pressure lubricant supplied with your Erson cam on the bottom of the lifters, the lobes of the cam and on the distributor drive gear. Do not use this lube on the tips of the pushrods, the sides of the lifters or on the rocker arms. Use a quality oil when installing roller tappets.

BEFORE YOU TURN THE KEY

• Fill All of the Engine’s Fluids- Using a minimum of a SAE API SD, SE or better fresh clean mineral based oil, fill the engine to the proper level. Do not use synthetic oil during break-in. Fill the coolant system and follow the instructions on purging air from the system. With carburetor equipped engines, fill the carburetor to insure fuel is available immediately. Make sure that the ignition timing is properly set to insure immediate starting, without excess cranking of the engine.

• Pre-Lube the Engine- Using a oil pump priming tool such as those available from Mallory, spin the engine’s oil pump until you see pressure on the gauge or have oil at the rocker arms. Do not attempt to prime the engine using the starter motor!

• Proper Ventilation- Make sure that you do not start the engine without good airflow. That means have the overhead garage door open and the exhaust vented to the outside. If you have any doubts about sufficient airflow to the engine, push the car out of the garage to make sure the radiator can draw in plenty of air. Having a fan to blow fresh air through the garage is a plus.

• Exhaust System- If at all possible, start the car with a muffled exhaust system hooked up and operational. It makes it much easier to hear what is going on.

• Resist the Urge- Take a minute before you try to start the engine for the first time and double check that you are ready to go. Don’t take any short cuts or leave parts such as fan shrouds, air cleaner, wire looms, etc. off. Clean up the are around and especially under your vehicle. Pick up your tools and wipe up the floor so you can easily spot even a minor leak.

• Be Prepared- Have extra coolant or a hose handy, clean rags, tools for tightening clamps, connections, etc. just in case. They need to be in place to make sure you have an uneventful break-in of the camshaft.

WHEN THE ENGINE STARTS

• Have a Helper- Now is the time for a helper. They can check the coolant level, check for oil and fluid leaks, and proper operation of underhood accessories. Air pockets in the coolant system are common so make sure the recovery bottle is checked and filled as necessary. You cannot count on the temperature gauge. Temperature gauges are only accurate if the sensor is submerged in coolant and will not give an accurate reading if in an air pocket.

• Do Not Idle the Engine- As soon as the engine starts, raise the rpm to 2,000 rpm. You should also constantly vary the RPM between 2,000 and 3,000 RPM for the first 20 minutes. This is the only way to insure proper lubrication during this critical period since the camshaft to lifter contact area relies almost exclusively on oil splash from the crank and connecting rods. Make sure that you run the engine for a full 20 minutes using this procedure. It will seem like forever, but it is one of the most important steps to insure long, dependable performance.

Once Break-in is Complete- Drain and replace the engine oil and filter with new, fresh oil and a new filter. Recheck for any fluid leaks and check all fluid levels. If you installed a mechanical lifter style camshaft, flat faced or roller style, the valve adjustment should be rechecked at this time with the engine fully warmed up. Hydraulic lifter equipped engines should not require any readjustment.

Proper maintenance is important for any vehicle. Frequent oil changes, with a new filter is one of the easiest ways to insure your vehicle will deliver the performance you want for many long happy miles.


ID ADD, USE a GOOD MOLY BASE ASSEMBLY LUBE AND A HIGH ZINC CONTENT OIL AND SOME G.M. E.O.S. TO THE OIL
Originally Posted by Howards Cams Catalog p.161
The first few minutes of engine operation after installing a
new cam are critical. It takes time for the engine’s oiling
system to reach efficiency and while you’re waiting for
that to happen, metal-to metal contact can occur. If it
does, something is going to fail then or later. Especially
critical is the lifter/cam lobe area. If metal touches metal
here without benefit of solid lubrication, galling will occur
and something (the lifter, the lobe or both) is going to fail.
To prevent these and similar problems not covered by any
warranty, please follow the steps outlined here:
1) New lifters must be installed with any new cam installation.
The surface of a new lifter, which rides on the cam
lobe, has a spherical shape with a 0.002” crown, which is
almost impossible to detect. Used lifters won’t have that
crown and will quickly destroy cam lobes (see Fig. 2.
“How to Install a Performance Camshaft”). Note: that if
you later take your engine apart, lifters must be reinstalled
in the bore from which they were removed. Each lifter
wears in a way that mates it to a given cam lobe; switching
lifters is the same as using old lifters with a new cam.
2) Install the valve train components (lifters, valves,
springs, etc.) recommended by the cam manufacturer.
These items have been tested and proven for compatibility
with the cam.
3) Coat the cam lobes, distributor drive gear, lifter cam
faces and other critical components with a moly-disulfide
lube like our Camshaft and Engine Assembly Lube for
protection against metal-to-metal contact during initial
break-in.
4) Check the entire valve train for interference and adequate
clearance during assembly. The four areas of major
concern are covered in “How to Install a Performance
Camshaft.”
5) Fill the oil pan with top-quality MS-DG engine oil meeting
the SAE or API specifications set by the engine manufacturer.
A Pennsylvania-based detergent oil is preferred. Use a
straight viscosity of 20W or 30W for break-in; do not
switch to a multi-viscosity oil until after the break-in period.
For flat tappet applications, a zinc-phosphorous
additive must be added, such as MAX Z.P.M. (99000),
to the engine oil during break-in.
6) Before starting the engine be sure:
• The valves are correctly adjusted. Set solid lifters 0.003”
to 0.005” tighter than specified.
• To prime the oil system by turning the oil pump manually
until pressure is indicated on the oil gauge. Be sure
crankcase is filled to proper (normal) level.
• To put gas in the carburetor float bowls, prime the
accelerator pump and have gas in the tank.
• There’s water in the radiator.
• The battery is charged.
• Nothing will get caught in the fan, fan belts, and alternator/
generator belt or by the crankshaft. Check the
entire engine compartment for loose tools or parts.
• Ignition timing is set accurately.
To avoid galling, the engine should start right away.
Avoid a long grind on the starter and over cranking the
engine before firing. Low oil pressure could damage
camshaft and other components.
7) When the engine fires, immediately rev it to 1800-2400
rpm. Do not idle the engine for the first 20 minutes. Much
of the oil for lubrication and cooling the camshaft comes
from crankshaft splash. Below 1800 rpm, turbulence is
probably not enough to lubricate the cam fully. The
engine may be run on the road or in the shop, but the
shop is best. If adjustments are required during the first
20 minutes, shut the engine off.
8) Vary rpm frequently during this initial break-in period to
change oiling within the engine.
9) After completing the break-in period, change the
engine oil and filter. Regularly change engine oil and filter
and maintain proper valve lash adjustment on solid
lifter engines.
Following these steps will extend the trouble-free life of
your cam and assure you of an engine that delivers the
maximum possible performance.

(lack of proper clearances geometry or failed proper lubrication)
lobelif.png

and some potential areas that might be improved or potential solutions
installedheight.gif

Ok, in most cases where a lifter or cam lobe contact area fails,during the first few thousand miles or hours of run time, its related to a clearance issue or mis-matched components, or less than ideal rocker geometry.
yeah! I know your 100% sure you got it correct but after checking dozens of engines guys brought into my shop , I find an amazing amount of areas that get either ignored or over looked, or the engines owner/builder never even considered or understood the potential clearance issue in that area!

surface preparation of both the lifter base and cam lobes with a high quality moly assembly lube that will embed micro platelets in the metallic surface flaws adds considerable wear protection
The Moly platelets that make up the protective layers on your engine surfaces slide across one another very easily. Instead of metal rubbing against metal, you have Moly platelets moving across one another protecting and lubricating the metal engine parts.
cambreakin.jpg

crn-99004.jpg

MOLY adds a great deal of lubrication to sliding metal surfaces , as it embeds in the micro fissures in the metallic surface's
lab_additive_test_results1.jpg



This coating effectively fills in the microscopic pores that cover the surface of all engine parts, making them smoother. This feature is important in providing an effective seal on the combustion chamber. By filling in the craters and pores Moly improves this seal allowing for more efficient combustion and engine performance.
nosqueeze.jpeg

This overlapping coating of Moly also gives protection against loading (perpendicular) forces. These forces occur on the bearings, and lifters. The high pressures that occur between these moving parts tend to squeeze normal lubricants out.

USE OF PROPER OILS WILL BE MANDATORY
Oil categories:

*** Over 90,000 psi = OUTSTANDING protection

*** 75,000 to 90,000 psi = GOOD protection

*** 60,000 to 75,000 psi = MODEST protection

*** Below 60,000 psi = UNACCEPTABLE protection




1. 5W30 Pennzoil Ultra, API SM = 115,612 psi
I have not been able to find this oil with the latest API SN certification. The bottle says, “No leading synthetic oil provides better wear protection . For once, a product hype turns out to be true.
zinc = 806 ppm
phos = 812 ppm
moly = 66 ppm

2. 10W30 Lucas Racing Only = 106,505 psi
zinc = 2642 ppm
phos = 3489 ppm
moly = 1764 ppm
NOTE: This oil is suitable for short term racing use only, and is not suitable for street use.

3. 5W30 Mobil 1, API SN = 105,875 psi
zinc = 801 ppm
phos = 842 ppm
moly = 112 ppm

4. 0W30 Amsoil Signature Series 25,000 miles, API SN = 105,008 psi
zinc = 824 ppm
phos = 960 ppm
moly = 161 ppm

******* 10% below number 1 = 104,051 psi ********


5. 10W30 Valvoline NSL (Not Street Legal) Conventional Racing Oil = 103,846 psi
zinc = 1669 ppm
phos = 1518 ppm
moly = 784 ppm
NOTE: This oil is suitable for short term racing use only, and is not suitable for street use.

6. 5W50 Motorcraft, API SN = 103,517 psi
zinc = 606 ppm
phos = 742 ppm
moly = 28 ppm

7. 10W30 Valvoline VR1 Conventional Racing Oil (silver bottle) = 103,505 psi
zinc = 1472 ppm
phos = 1544 ppm
moly = 3 ppm

8. 10W30 Valvoline VR1 Synthetic Racing Oil, API SL (black bottle) = 101,139 psi
zinc = 1180 ppm
phos = 1112 ppm
moly = 162 ppm

9. 5W30 Chevron Supreme conventional, API SN = 100,011 psi
This one only costs $4.29 per quart.
zinc = TBD
phos = TBD
moly = TBD

10. 5W20 Castrol Edge with Titanium, API SN = 99,983 psi
zinc = TBD
phos = TBD
moly = TBD
titanium = TBD


11. 20W50 Castrol GTX conventional, API SN = 96,514 psi
zinc = 610 ppm
phos = 754 ppm
moly = 94 ppm

12. 30 wt Red Line Race Oil = 96,470 psi
zinc = 2207 ppm
phos = 2052 ppm
moly = 1235 ppm
NOTE: This oil is suitable for short term racing use only, and is not suitable for street use.


THE LINKS and SUB LINKS GO INTO THE PROBLEM IN MORE DEPTH

http://garage.grumpysperformance.co...k-after-a-cam-lobe-rod-or-bearings-fail.2919/

http://garage.grumpysperformance.com/index.php?threads/assembly-lube-summary.6352/#post-56615

http://garage.grumpysperformance.com/index.php?threads/magnets.120/#post-49772

http://garage.grumpysperformance.com/index.php?threads/not-getting-oil-to-rockers.4537/#post-31114


the non-adjustable rocker engines from 1991 and up are much less tolerant than the earlier engines to cam changes, and any cam and lifter damage DID result in metallic trash in the engines oil system

http://garage.grumpysperformance.com/index.php?threads/casting-numbers-vin.93/

http://garage.grumpysperformance.co...ck-chevy-gen-v-vi-to-adjustable-rockers.4564/

http://garage.grumpysperformance.com/index.php?threads/rocker-push-rod-wear-issues.9815/#post-56570

http://garage.grumpysperformance.com/index.php?threads/magnets.120/#post-49772

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

READ, ALL THESE LINKS AND SUB LINKS, ALL THE WAY THROUGH CAREFULLY
http://garage.grumpysperformance.co...k-after-a-cam-lobe-rod-or-bearings-fail.2919/

http://garage.grumpysperformance.com/index.php?threads/cam-wear-articles-you-need-to-read.282/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.co...t-compressed-when-installed.11356/#post-51869

http://garage.grumpysperformance.co...-pushrods-and-check-info-you-might-need.5931/

http://garage.grumpysperformance.co...ectly-and-get-it-to-last-cam-install-info.90/

http://garage.grumpysperformance.com/index.php?threads/magnets.120/



while the links and sub links will take a few days to read through youll get a good education thats well worth the effort, theres books and a few videos , plenty of reference material and several dyno tests


http://garage.grumpysperformance.com/index.php?threads/another-496bbc.5123/

http://garage.grumpysperformance.com/index.php?threads/454-bbc-on-the-cheap-well-to-start.11739/

http://garage.grumpysperformance.co...-building-a-peanut-port-big-block-combo.2900/

http://garage.grumpysperformance.com/index.php?threads/468-build.11794/

http://garage.grumpysperformance.co...g-block-head-comparison.319/page-2#post-49217

http://garage.grumpysperformance.com/index.php?threads/big-block-chevy-info.710/#post-49737

http://garage.grumpysperformance.com/index.php?threads/newby-from-ontario-canada.12003/#post-57367

http://garage.grumpysperformance.com/index.php?threads/cam-break-in-procedure.130/#post-728

http://garage.grumpysperformance.co...oil-passages-and-improved-oil-flow-mods.3834/

http://garage.grumpysperformance.com/index.php?threads/rhodes-lifters.1552/#post-6067

summit said:
I have a small block Chevy in a ’66 Chevy II that seems to run pretty good but now I’m not so sure. It’s a 383 small block with a set of no-name aluminum heads, a Lunati hydraulic flat tappet Voodoo cam (227/233 degrees at 0.050 inches with 0.489/0.504-inch lift), a Performer RPM intake, and a 650 cfm Holley carburetor. The engine runs fine – doesn’t misfire or do anything funny but I am concerned that it seems to stop pulling once the tach gets above 5,000 rpm. The ignition is an HEI with good Moroso wires and new spark plugs. The motor has been in the car for several years but about a year ago we changed to that Lunati Voodoo cam. It just seems like it lays down in high gear. Any ideas?

J.B.

Jeff Smith:
One of the challenges of the whole hot rodding hobby/sport is that there are literally millions of combinations of parts from which to choose. With hundreds of companies making thousands of parts, the permutations of just cylinder heads, camshafts, intakes, and compression ratios becomes a blur of options. So it’s not surprising that you may have difficulties.

But I have some possible solutions.

You didn’t mention whether you were feeding the engine with a mechanical or electrical fuel pump. I’ll assume that the pump is probably mechanical. First thing to do is to check the fuel filter for obstructions. The fuel filter is often an afterthought and cheap, restrictive filters can reduce output from the pump. The pump may be capable of supplying fuel for low rpm and part throttle operation but at higher rpm, there is insufficient fuel pressure and volume due to a filter restriction, so start with that inspection first. Your 650 cfm Holley is big enough that it’s not really a restriction with regard to airflow.

The best way to check for adequate fuel flow is to install a fuel pressure gauge in between the pump and the carburetor and upstream of the fuel filter. This does not have to be an expensive Auto Meter gauge permanently mounted on the cowl – although this is a good idea. Instead, you could borrow or buy an inexpensive fuel pressure/vacuum gauge and plumb it into your fuel delivery system. Use a long length of rubber hose and place the gauge on the cowl where you can read it while driving. I’ve actually duct taped gauges to the lower portion of the windshield when doing diagnostic work like this. Next, run the car somewhere safe where you can make multiple passes past 5,000 rpm and monitor the gauge. Decent fuel pressure for a carburetor is 4 to 6 psi. It’s possible that at the higher engine speeds the pressure will begin to drop. If it falls below 3.5 psi, it’s possible that you’ve found the problem. Holley and several other companies make really good mechanical fuel pumps for a small-block. For example, Holley offers an 80 gallon per hour (gph) mechanical pump (PN 12-834) that will deliver more than enough fuel for our application. This pump should be able to easily supply 4.5 to perhaps 6 psi at WOT while supplying more than enough fuel volume.

If after checking fuel pressure you learn that your existing pump is working just fine, then we have another suggestion.

To be more accurate we would need more information on the valve springs and cylinder heads. But with an emphasis on the budget aspect, often these heads come with valve springs that are not up to the task of controlling the valves at high rpm. This is aggravated somewhat by the Lunati Voodoo camshaft. The Voodoo line offers great performance from a relatively short duration. Lunati accomplishes this by being fairly aggressive with the rate at which the intake and exhaust lobes open the valves. The Lunati description for this cam is “Makes unequaled power to 6,200 rpm with proper valve springs.” The key here is the connection to the valve springs.

Our experience with the Voodoo line underscores this load on the valve springs. You didn’t mention if you were running stock 1.5:1 ratio rockers. If so, that’s fine, but with 1.6:1 rockers, the additional ratio puts even greater forces on the springs because the rocker accelerates the valve even faster to achieve the greater lift. A combination of weak valve springs with a Voodoo cam and 1.6:1 roller rockers could easily cause the problem you are experiencing. Most guys would call this valve float. What they don’t tell you is how to fix this. That’s what we’re going to do.

The most accurate definition of valve float is when the spring loses control of the valve. When this happens, the first indication is when the intake valve bounces off the seat as it closes. This may not sound like a big deal, but the results will kill power. When the valve bounces off its seat, this occurs at the same time that the piston is rising in the bore and creating cylinder pressure. But when the valve bounces off the seat, it allows some of this pressure to escape. The reason the valve bounces is because the spring cannot exert enough load to keep the valve closed. When the valves bounce off the seat multiple times, the engine loses power and often can’t even achieve the rpm. This is classic valve float. Of course, the end result is a dramatic loss of power.

The most common fix for this problem is a stiffer valve spring, especially if the existing springs are on the weak side. What you should do is remove one spring and have it tested at a local machine shop. This will tell you the status of your springs. Stock replacement valve springs generally do not produce much more than about 90 to perhaps 100 pounds of seat load with an installed height of 1.750-inch. For a stock or mild performance cam, this is sufficient load. But with a performance camshaft like the Voodoo cam even Lunati’s base replacement spring is rated at only 98 pounds with at a 1.750-inch installed height and 286 pounds of force at 0.500-inch valve lift. My guess is that this spring will probably not work as well as something with a little more closed pressure, especially if the plans call for a 1.6:1 rocker. While a dual spring could do the job, this often places excessive load on the cam at peak lift. Instead, Lunati recommends using its new line of Signature Series Ovate Beehive springs. The complete valve spring and retainer kit (PN 74818K2) includes new beehive springs, retainers, and the necessary locks all under one part number.

This beehive spring offers a substantial increase in seat load from the previous spring’s 98 pounds at 1.750 to the beehive’s 130 pounds at a taller 1.800. Now that we know how valve float starts, perhaps you can see that a spring with essentially 30 percent more seat load will have a much better chance of keeping that intake valve closed at higher engine speeds. There are other added benefits to using a beehive spring but in the interest of brevity, we’ll save that discussion for another time. Changing over to the better valve springs will probably be the thing that will improve your engine’s performance and bring your small block back to life!


these links may be useful
http://garage.grumpysperformance.com/index.php?threads/adjusting-valves.196/

http://garage.grumpysperformance.co...cally-tracking-down-a-valve-train-noise.6237/

http://garage.grumpysperformance.com/index.php?threads/metal-in-oil.10875/#post-47688


http://garage.grumpysperformance.com/index.php?threads/cam-wear-articles-you-need-to-read.282/

http://garage.grumpysperformance.co...k-after-a-cam-lobe-rod-or-bearings-fail.2919/
 
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Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
I'm looking into upgrading my rocker arms on my 454 from the stock stamped steel units. I have 3 different brands in mind that have a 1.8 ratio. All three are about $3 difference in price. The brands are Harland sharp, Howard's (both of these are aluminum) and then the crower enduro which are stainless steel.

the crower steel units will have a longer fatigue life and the bearing trunions are replaceable so they can be rebuilt after 60K-80K

,Fatigue limit, endurance limit, and fatigue strength are all expressions used to describe a property of materials: the amplitude (or range) of cyclic stress that can be applied to the material without causing fatigue failure.[1] Ferrous alloys and titanium alloys[2] have a distinct limit, an amplitude below which there appears to be no number of cycles that will cause failure. Other structural metals such as aluminium and copper, do not have a distinct limit and will eventually fail even from small stress amplitudes. In these cases, a number of cycles (usually 107) is chosen to represent the fatigue life of the material.
tappet%20adjustment_zps8vi9yxmu.jpg

fatiguel.PNG


heres a bit of useful related push rod length info
Big Block Chevy, Standard Length Big Block Intake 3/8" / .080" 8.275"
295-7941-8 Big Block Chevy, Standard Length Big Block Exhaust 3/8" / .080" 9.250"
295-7969-8 Big Block Chevy, Standard Big Block +.100" Long Intake 3/8" / .080" 8.375"
295-7979-8 Big Block Chevy, Standard Big Block +.100" Long Exhaust 3/8" / .080" 9.350"
295-7951-8 Big Block Chevy, Standard Length Big Block Tall Deck Intake 3/8" / .080" 8.675"
295-7961-8 Big Block Chevy, Standard Length Big Block Tall Deck Exhaust 3/8" / .080" 9.650"
295-7800 V8 396-454 Retro Fit Pushrod Set, Intake & Exhaust, 1965-Present
3/8" / .080"
3/8" / .080" 7.725 Int.
8.675 Exh
295-7913-16 Small Block Chevy, Standard Length Small Block Chevy 3/8" / .080" 7.800"
295-7984-16 Small Block Chevy, +.100" Long 3/8" / .080" 7.900"
295-7934-16 Big Block Ford, Standard Length Ford `72-'78 429-460 3/8" / .080" 8.550"
295-7951-16 Big Block Ford, Standard Length Ford `69-'71 429-460 3/8" / .080" 8.675"
295-7582-16 Oldsmobile, Std Length 455 5/16" 9.550"
http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-57678

http://garage.grumpysperformance.co...train-clearances-and-problems.528/#post-66870

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/
 
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enigma57

reliable source of info
Very informative! Thanks, Paul! I have a question...... Working with an OEM small block Chevy cast-iron head...... At what valve lift is it necessary to go to 0.100" longer valve stem?

Thanks,

Harry
 

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
The answer to selecting the proper valve length in relation to the cam lift, and valve spring load rates, depends on the engine valve train geometry and the cylinder head design,
it differs from intake to exhaust on most engines also.
I've usually found longer valves are required if the valve lift exceeds about .630,
but theres no rock solid rule, you need to do some research and call your machine shop and the cylinder head manufacture.
the load rate also plays a significant part in that decision,
with thinner valve spring seats, that is not always an option,
as higher load rates require thicker castings for structural rigidity.
valve lift alone withing reasonable limits, has little to do with the need for longer valves, but as the lift increases the difference between the spring installed height and its spring bind or coil stack obviously changes.
if your standard valve spring has lets say a 1.70 installed height and a 1.20 coil bind or stack height you would generally be looking at .500 difference, subtract the .060 minimum clearance,
added to prevent binding issues for coil bind, that only leaves you .440 useful valve clearance.
now you can machine the heads in the valve spring seat area only minimally as the valve spring seats are over the coolant passages and generally ,
the manufacturers will tell you you can only machine the valve seat so far from the O.E.M. original location,
and in many cylinder heads you can't machine deeper without reducing the heads functional strength or causing problems.
if you can,t machine down into the valve spring seat, your other option is a longer valve stem, or if you just need about .040-.050 maybe you get by with off-set valve locks, or retainers, and longer push rods and valve lash caps.
but most machine shops would prefer the longer valves and longer push-rods to maintain the proper valve train geometry.
valves are generally available . .100,..200, .300 longer lengths for popular engines and you can certainly use a micrometer to measure similar valves from a different engine, if the proper length is not easily available.
be aware that theres both different valve stem diameters, valve lock location, valve lock designs, different intake and exhaust valve steels that you can,t interchange.
one of the old performance tricks some guys used to use on a BBC, engines with turbos, was to replace the 1.88 exhaust valves with 2.00 intake valves from a 430 lincoln engines that were made from exhaust steel.
vspr1.jpg


Installedsp.jpg


drawsdf.jpg


portsd2.jpg

before as cast
portse1.jpg
 
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enigma57

reliable source of info
Many thanks! I just wanted to make sure I wasn't going past that limit on this engine, Paul.

Best regards,

Harry
 

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
youll generally see no issues with the stock rocker to stud clearances below about .530 lift,
but as always theres going to be exceptions so it needs to be carefully checked and verified, assuming is a quick route to expensive problems
 

enigma57

reliable source of info
Thanks again, Paul. That is good to know and I will make a note of it. What I am working with are some NOS big block rockers, GM part number 6258611 which are for 1965 - 1969 396 & 427 high performance engine.

As I soon found out when putting together a matched set...... GM used this same part number for both the M-stamped rockers and the L-stamped rockers. M-stamped are 1st design (1965 - mid 1966) and L-stamped are 2nd design (late 1966 - 1969).

They seem to be identical except for identifying stamp (M or L) and the fact that the 1st design M-stamped rockers use smooth, shiny pivot balls and the 2nd design L-stamped rockers use grooved pivot balls same dark colour (nitriding?) as rocker arms.

Anyway...... I ended up with a complete set of M-stamped rockers (and a couple of L-stamped rockers I suppose I will keep for spares). Both types measure between 0.693" and 0.695" as to slot length.

I looked up high performance 396 solid lifter cam specs for those years. 1965 cam (part number 3863144) had valve lift of 0.497" int. and 0.503" exh. and 1966 - 1969 solid lifter cam (part number 3963143) had 0.5197" lift for both intake and exhaust. So I figured these rockers would be OK with valve lift around 0.500", but of course I will double check clearances during assembly as you suggest. Better safe than sorry.

BTW...... Whilst I am thinking about it...... Is there any real advantage to using the pivot balls with oiling grooves rather than the smooth pivot balls with an engine running a hydraulic flat tappet cam on the street having between 230 and 240 degree duration @ 0.050" and moderate lift (0.500" or less)? So far, I have found only the smooth pivot balls in GM NOS. Grooved pivot balls seem to be much harder to find and I am hesitant to run aftermarket grooved pivot balls on original GM rockers (not sure how well aftermarket pivot balls would fit OEM rockers).

Thanks,

Harry
 

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
the grooved rocker pivot ball design was an effort by G.M. engineering to economically solve the issue of marginal oil flow causing rocker ball galling, and resulting noisy, or broken valve trains
some roller rocker too retainer combo clearance issues cause problems easily solved with beehive springs and smaller retainer diameters
beehivesprcl.jpg

for several years even stock BBC engines ,(the markVI and mark V) as opposed to the (mark IV earlier BBC engines)
also don,t use adjustable rocker arms if your running a stock cam and valve train with stock O.E.M. heads you probably can get by without them,
swap to a higher lift cam and a longer duration and aftermarket heads and better valve strings and in my opinion,
you would be very foolish to build and use a performance BBC engine without adjustable push rod guide plates
what you really should do is order these
Dart 27001230-4 - Dart Pushrod Guideplates

301-27001230-4.jpg



viewtopic.php?f=44&t=2839&p=7344&hilit=adjustable+guide#p7344

http://garage.grumpysperformance.com/index.php?threads/busted-rocker-stud.689/
bbcrk1.jpg


dualspring.jpg



offsetlockheight.jpg

the grooved rocker pivot ball design was an effort by G.M. engineering to economically solve the issue of marginal oil flow causing rocker ball galling, and resulting noisy, or broken valve trains
some roller rocker too retainer combo clearance issues cause problems easily solved with beehive springs and smaller retainer diameters
beehivesprcl.jpg

for several years even stock BBC engines ,(the markVI and mark V) as opposed to the (mark IV earlier BBC engines)
also don,t use adjustable rocker arms if your running a stock cam and valve train with stock O.E.M. heads you probably can get by without them,
swap to a higher lift cam and a longer duration and aftermarket heads and better valve strings and in my opinion,
you would be very foolish to build and use a performance BBC engine without adjustable push rod guide plates
what you really should do is order these
Dart 27001230-4 - Dart Pushrod Guideplates

301-27001230-4.jpg



viewtopic.php?f=44&t=2839&p=7344&hilit=adjustable+guide#p7344

http://garage.grumpysperformance.com/index.php?threads/busted-rocker-stud.689/
bbcrk1.jpg


dualspring.jpg

offsetlockheight.heic

offsetlockheight

[/img]
offsetlockheight.heic

offsetlockheight
 
Last edited:

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
about_valvespringsa.jpg

in-depth-review-nextek-valve-spring-400x316.jpg

Stronger beadlock 10-degree locks (A) are required with radius-style valve stem grooves (B). Conventional square-shoulder valves (C) accept both corresponding 7-degree (D) and 10-degree (E) keys. Note the 10-degree locks increased thickness. Most titanium valves have a pressed-in, hardened tip (F). In its absence, a lash cap (G) is mandatory for preventing tip wear.
http://www.summitracing.com/search/part ... ve%20locks
the locking ridge in the valve keeper locks can be selected to move the retainer up at least .030-, .050, .060 and the valve spring retainers can also be purchased to move the valve spring retainer a similar .050 or more in either direction on the valve spring allowing at least a .100 or greater change in valve spring installed heights

be aware that there are both 7 degree and 10-degree valve stem locks and valve spring retainers
and there are several dozen versions some have rounded valve stem recesses
some have square recesses and there's valve stems with multi-groove locks, it should be obvious that the valve spring retainers and valve keepers MUST match the valve diameter and type of locking grooves and the retainers used must match the valves and keeper and spring diameters

Manley%20LOCCAP%20SYSTEM.gif

halderman-ch031-lecture-71-728.jpg

21-7.jpg

valve_locks.jpg



worth watching, just for the tips on new head inspection

https://www.jegs.com/p/COMP-Cams/Comp-Cams-Valve-Stem-Locks/753201/10002/-1
valvespringinstalled.gif

bbcspring2.gif

you need .090 clearance between the retainer to valve seal and a TOTAL of .060 clearance MINIMUM on the valve spring coils from spring bind, or solid stacking the spring coils

drawsdf.jpg

installedheight.gif

K1060-100.jpg

notice the lock groove can be moved to increase or decrease the valve spring installed height
K1030-100.jpg

cca-601-16.jpg


offheight.heic
 
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