Understanding Valve Spring Bind Height +.060" Safety Margin

Indycars

Administrator
Staff member
Quite often I see this graphic showing 0.060" between the coils. If this was right, then the actual safety margin would
equal nearly 1/4" and NOT 0.060". With roughly 5 coils in the spring then there are 4 gaps between the coils, therefore
4 x 0.060 = 0.24" or nearly 1/4". Looking at the graphic also makes me think that I could use a wire gauge of 0.060"
and measure directly between the valve spring coils at maximum valve lift to determine if I had the correct clearances.

What we are really trying to determine is if the spring height at maximum valve lift is 0.060" greater than spring bind height.

Maybe I don't understand this concept.......am I right or wrong ???
 

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grumpyvette

Administrator
Staff member
Re: Understanding Valve Spring Bind Height +.060" Safety Mar

Indycars said:
Quite often I see this graphic showing 0.060" between the coils. If this was right, then the actual safety margin would
equal nearly 1/4" and NOT 0.060". With roughly 5 coils in the spring then there are 4 gaps between the coils, therefore
4 x 0.060 = 0.24" or nearly 1/4". Looking at the graphic also makes me think that I could use a wire gauge of 0.060"
and measure directly between the valve spring coils at maximum valve lift to determine if I had the correct clearances.

What we are really trying to determine is if the spring height at maximum valve lift is 0.060" greater than spring bind height.

Maybe I don't understand this concept.......am I right or wrong ???






yodam.jpg

valvetip.jpg

13cal.jpg

http://www.racingsprings.com/



READ THIS THREAD AND RELATED LINKED INFO

http://garage.grumpysperformance.co...rdering-correct-custom-length-pushrods.14241/

http://garage.grumpysperformance.co...-loads-and-installed-height.10709/#post-46658
your correct the illustration confusing and miss represents the clearance they MEAN .060 TOTAL clearance not .060 per coil


coil bind height + plus lift + plus .060 clearance = equals max cam lift
longslot.jpg


long slot rockers are far less likely to bind on rocker studs

example if coil bind is 1.25" and installed height is 1.90 " then the .060 minimum clearance, being mandatory , leaves a max cam lift of .590
the rocker is basically a pivot point between the valve and push rod roughly centered on the rocker stud, if the rocker is not running smoothly thru its intended arc theres an excellent chance you've got clearance or rocker geometry issues,you will need to verify the correct rocker geometry then order the push rod length to match the correct rocker geometry and clearances in the valve train.
youll need to verify you have enough valve train clearance at full valve lift to both prevent the retainer from getting closer than .060-.090- from the valve seals and .060 minimum from spring bind or having the spring fully compressed

file.php


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
once youve got that correct you use the valve spring/rocker geometry check tool to get the APPROXIMATE LENGTH REQUIRED, and

an adjustable length push rod

adjst.jpg

cca-7901-1.jpg


https://www.crower.com/clearance.html?cat=1541

you might want to buy a few of these while they are on sale at a reduced price

heres a bit of useful related push rod length info (POSTED HERE) youll want to select the correct set or SETS for your shop

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"



auto0075kn.jpg


pushrodr1.jpg

you should very carefully inspect any used rockers or push rods before you use the two, as any previous wear areas will in most cases cause rapid wear on the new component mated to the worn surface, and obviously the rockers must be clearanced correctly and have obvious oil flow from the push rods
pushrodr2.jpg

HERES A SBC with a push rod checker installed showing an obviously too long for the application push rod.
pushrodr3.jpg

since the early mark IV BIG BLOCK engines use two different length push rods (INTAKE/EXHAUST) the checker is designed to be reversible, and marked to indicate which position it needs to be used with, to indicate the correct length push rods
notice in the pictures directly above and below it appears the push rods are a bit too long

pushrodr4.jpg

pushrodr5.jpg

pushrodr6.jpg

notice in the two pictures above the pushrods are the correct length as the checker sits on both the valve tip and push rod tip
pushrodr7.jpg

pushrodr8.jpg


obviously the push rods must be long enough to clear the push rod guide plates rockers through the full arc of movement and not bind on the springs retainers or rocker stud at full lift or while the lifters seated
pushrodr9.jpg

pushrodr10.jpg

push rods should also not rub on the guide plates at any point in the arc as it moves the valve from seated to full lift and back too seated
pushrodr12.jpg

pushrodr13.jpg

pushrodr14.jpg

pushrodr15.jpg


read link
http://www.racingsprings.com/Store/1400 ... ive/sku/32

http://www.racingsprings.com/Store/1200 Series/sku/5

viewtopic.php?f=52&t=181

viewtopic.php?f=52&t=1376&p=3030&hilit=pushrod+length+checker#p3030

http://www.stockcarracing.com/tipstrick ... eight.html
pic191.jpg


pic20%20(2).jpg


springmic.jpg

valvespringmic.jpg

pro-66832_cp.jpg

otc-4573_w.jpg



http://www.hotrod.com/techarticles/engi ... to_15.html

occasionally youll see guys post advice , to remove the inner of the two springs on dual valve springs during the cam break-in process to reduce the lifter to cam lobe load rates, thus reducing the potential for rapid wear during the critical break-in process,the problem I see occasionally is that some guys confuse single valve spring with dampers with dual springs.
typically chevy valve springs use single or dual valve springs usually with an inner friction damper
vswda.jpg

single valve spring with friction damper ABOVE
vswds3a.jpg

vswds2a.jpg

dual valve springs with friction damper (BOTH PICTURES ABOVE)
dvsps4.jpg

dual valve springs without damper


as always its isolate and carefully test,don,t assume you know whats causing the noise, or problem like most guys do, and try to prove it, look at the facts!as you find them,and let them lead you to the cause, don,t ever assume a new part can,t be defective or that you could not have installed it incorrectly, WE ALL SCREW UP OCCASIONALLY!. THINK THINGS THRU,BE OBSERVANT! Id suggest you pull the valve covers, and carefully inspecting the rockers and valve train components for indications of excessive wear,and look at the valve springs and check for coil bind , and rocker to rocker stud clearance,and rocker to jam nut clearance, rocker to retainer clearance,especially if the cam you installed has over .480 lift and your still using the stock valve springs,and then place your hand on each rocker as the engine idles and listen for changes in the sound and feel the rocker movement, a defective or improperly installed rocker arm,or one binding on the jam nut can and will make that sound and exhaust rockers are more prone to fail, if you adjusted the rockers without having the engine idle try it the old way at idle ,yeah, I know,what you heard, try it any way.
you might also find that pulling one spark plug wire off the distributor cap at a time and replacing it then moving to the next and removing that one, etc. etc. will help you locate the cylinder causing the ticking sound, by the change in sound when that cylinder does not fire.
you might also do a compression test and check your ignition timing curve, look for vacuum leaks and post clear detailed pictures of each spark plug labeled as to the cylinder as its condition can tell you a great deal about the combustion in that cylinder
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/
retain7.jpg

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

rockerh2.png

valvespring3.JPG

lash_caps.jpg

at times lash caps or longer push rods will be needed to change the valve train geometry to gain rocker clearance or get the proper geometry
worn_cam_lifter1.jpg

AND YES CAM LOBES AND LIFTERS FAIL..even ROLLER LIFTERS
ToastedLifter007.jpg

ToastedLifter008.jpg

ToastedLifter009.jpg

 
Last edited by a moderator:

Indycars

Administrator
Staff member
Re: Understanding Valve Spring Bind Height +.060" Safety Mar

What do you think, does this say it any better ???

Old Graphic .....

New Graphic .....
 

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grumpyvette

Administrator
Staff member
Re: Understanding Valve Spring Bind Height +.060" Safety Mar

yes your correct thats a huge improvement

please put a note, (total clearance between spring coils, at max lift equals a minimum of .060) on that diagram

yes you need to as stated, many times on this and other websites, check all your valve train clearances carefully, the cam spec. card that came with your cam should indicate the ideal matching spring load rates and clearances required.
drawsdf.jpg


those heads (keep in mind that price is for a single (1) cylinder head)
https://www.summitracing.com/parts/tfs-30410001/overview/

OBVIOUSLY YOULL WANT THE CORRECT VALVE SPRINGS

http://garage.grumpysperformance.co...steam-holes-posted-by-dennyw.2991/#post-57455

http://www.competitionproducts.com/1500-1585-OD-Valve-Springs/products/2631/1/0

https://www.summitracing.com/search/part-type/valve-springs

https://www.iskycams.com/cart/valve-springs-c-99.html

http://www.cranecams.com/userfiles/file/334-343.pdf

https://www.racingsprings.com/Valve-Spring/Store/13

http://www.lunatipower.com/Category.aspx?id=23

http://www.pspring.com/products/engine-valve-springs/

http://www.competitionproducts.com/Valve-Springs/departments/49/

http://psisprings.com/products/

http://www.compcams.com/Products/CC-'Valve Springs By Usage'-0.aspx

http://www.racingsprings.com/Beehive-Valve-Springs

https://www.supertechperformance.com/valve-springs-p109

http://www.cvproducts.com/index.php/psi-springs/


you might also want to keep in mind theres a great deal more to setting up a valve train than slapping some springs and retainers and keepers on the valves.
read thru the links and sub links as theres a great deal of useful info, that youll want to know.
btw just a bit more info, there are valve spring retainers, valve spring seats, shims, valve retainer keepers etc. that can be used that have different sizes or depths that allow you to change the installed height, or relation of the spring to the valve stem , it compressed height, or the valve springs location in relationship to the stems locking groove
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
cca-4929.jpg


0607em_17_z+engine_assembly+shims.jpg



viewtopic.php?f=52&t=181
http://www.jegs.com/p/Crane/746983/10002/-1

http://www.jegs.com/p/Moroso/764349/10002/-1

http://www.jegs.com/p/Manley/940089/10002/-1

http://www.jegs.com/p/Comp+Cams/757964/10002/-1
2709946016.jpg

660-42379-16.jpg

valvespringseats.png

valsp1.jpg

valsp2.jpg

valsp3.jpg

valsp4.jpg


youll have to correctly measure the clearance on your heads with the valve springs and cam specs you selected too use to know if you have the correct valve spring installed height and clearances, failure to accurately check frequently results in very expensive repairs and to what new guys frequently blame on the cam when it was a installers ignorance that was the true cause.

https://www.summitracing.com/parts/pro-66902/overview/

https://www.summitracing.com/parts/sum-900032/overview/

https://www.summitracing.com/parts/rsc-pac-t902/overview/

pic16vc.jpg

pic19vc.jpg


springmicv.jpg

vsmt7a.jpg

pic18vc.jpg

pic20vc.jpg


vspr1.jpg

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

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

push rod to short
WIDE SWEEP ON VALVE TIP FROM ROCKER ADDS ADDITIONAL,
SIDE LOAD WEAR
long.jpg

push rod to long
correct.jpg

lash_caps.jpg

at times lash caps or longer push rods will be needed to change the valve train geometry to gain rocker clearance or get the proper geometry
push rod length correct
AS CLOSE TO CENTER AS POSIABLE BUT BEING CENTERED IS LESS IMPORTANT THAN MINIMAL SWEEP ON THE VALVE TIP< INDICATING MINIMAL SIDE LOADING

http://garage.grumpysperformance.co...-pushrods-and-check-info-you-might-need.5931/
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
a few simple tools will tell you if clearances are ok

12cal.jpg


Feeler-Gauge.jpg


READ THESE LINKS CAREFULLY

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

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

http://garage.grumpysperformance.co...steam-holes-posted-by-dennyw.2991/#post-57455

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

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

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

Indycars

Administrator
Staff member
Re: Understanding Valve Spring Bind Height +.060" Safety Mar

Anything else ???
 

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