Valve Adjustment 302 With Positive-stop Rocker Arm Stud

alfa1

Member
Hello guys,


Does anyone really know that the valves or the hydraulic lifters will not adjusted if there are positive-stop rocker arm studs installed?
Only tightened/torqued to the shoulder of the studs and go...

Its a 302 with iron cast heads...

Thanks Martin
 
The camshaft specs are:

Camshaft: Stage 2 from engine tech.

Camshaft Specifications:

Type: (Stage 2)

.050" Duration (Int/Exh): 214/ 224

Cam Lift (Int/Exh): .296" / .311"

Valve Lift (Int/Exh): .478" / .498"

Lobe Separation (Int/Exh): 108/ 116

RPM Range 1200-4700

Hydraulic Flat Tappet
 
https://www.diyford.com/machine-small-block-ford-heads-step-step/

http://www.pbm-erson.com/content/erson_fordtech

4610ill_280.jpg


https://www.amazon.com/Cams-4610-16-Diameter-Adjusting-Small/dp/B000CEO7GM

612Guxb-DkL._SL1500_.jpg

Erson-Home-1.jpg

FORD TECHNICAL INFORMATION

Throughout the years, Ford Motor Company has introduced and manufactured some of the automotive industries most powerful as well as reliable engines. From Henry Ford’s 4 cylinder flat heads found in the original Model T’s to the Ford modular V8 of the ‘90s, Ford has always been a leader in design technology. With contributions from such famous engine builders as Holman and Moody, Carol Shelby, Bill Strope, Bob Glidden, Jack Rousch and Robert Yates, Ford has continued to be a serious contender in the never ending wars at race tracks all over the world. In an attempt to inform our customers of some of the more important aspects of valvetrain assembly, with regards to Ford engines, we have assembled a brief Ford technical section. This section covers areas of concern to individuals modifying stock Ford valvetrains. For more in depth information, customers should acquire the Ford Motorsports SVO Performance Equipment catalog as it is an excellent source of information. For complete one-on-one tech talk, call Ford’s performance hot line at 1.810.468.1356.

Blocks
1985-95 302 Ford engines were equipped with hydraulic roller valve trains. These blocks have taller lifter bores than 1962-84 blocks. It is possible to install hydraulic flat tappet, mechanical flat tappet or solid roller type camshafts in these engines as long as the proper matching components are used. With regards to solid roller camshafts and lifters, be aware that smaller base circle camshafts allow the roller lifter to set lower in the lifter bore. This may cause interference between the lifters link bar retaining button or rivet and the lifter boss in the block. Clearance the block to allow .060” minimum clearance are interchangeable, the push rods are not.

289/302 Heads
To convert late 289/302 heads for use with mechanical tappets, all valves must be replaced with early (1963-66) type valves. Another option is to machine the valve stem keeper grooves to early dimensions. Rocker arms must be replaced with early Ford rockers (part no. C20Z-6564-A), or equivalent aftermarket roller tip rocker arms. For guide plates, part no. C90Z6A564B, and rocker arm studs, part no. C30Z-6A527-B, must be used to install guide plates. Late heads must have the guide boss machined .230” and tapped to accept the stud.

429/460 Engines
We have found a number of 429/460 engines with a 7° retarded crank sprocket. Be sure to check during cam installation that your engine does not have this sprocket. These engines also have no provision for adjusting the valves when a mechanical tappet camshaft is installed. The easiest method to provide adjustment is to use adjustable pushrods. It is possible to modify the heads to utilize the rocker arms and studs from the Super CJ engine.

Rocker Studs


POSITIVE STOP STUDS
Positive stop studs are stock on 1969- 76 302-351W and 1968-72 429 engines with hydraulic cams. These studs allow no preload adjustment. They work only on hydraulic cams with .519” lift or less. For high performance or racing applications, we highly recommend replacing positive stop studs with conventional screw-in studs and guideplates.

CONVENTIONAL STUDS
A few 289-302 engines and most engines with solid cams used this type of stud. A lock nut on the stud keeps the valve lash from changing.

Rocker Arms
2 types of studs and 3 types of rockers are available on Ford engines:

RAIL TYPE ROCKERS
Rail rockers were used on 1966-68 289 engines and 1968-76 302 and 351W engines. This type of rocker features a slot in the end of the rocker arm to maintain alignment on the valve tip. Rail rockers must be used with long stem valves.

FULCRUM ROCKERS
These were installed on 351C, 351M and 400 engines. They were also used on 429-460 engines that did not use guideplates. A fulcrum or “sled” and a bolt keep the rocker aligned. Models built before 1977 use a slotted pedestal to hold the fulcrum. Screw-in studs and guideplates are required when replacing fulcrum rockers.

A flat pedestal and a U-shaped guide were used on 1977- later 302-351W engines to keep the fulcrum rocker aligned. Our screw-in studs allow you to easily convert to stud-type rockers. These engines are equipped with long valves. This allows easy installation of rail rockers.

Shaft-Mounted Rockers
Shaft-mounted rockers were used on 352-428 engines. The stock rockers were well suited for cams with a lift of .550” or less. However, there is not enough preload for proper lifter operation when using cams with a lift of more than .550”. You must replace the stock rockers with adjustable rockers to use solid or hydraulic lifters with the higher lift cam.

Valve Locks
Some Ford engines (351C and 351M-400) use multi-groove valve locks. PBM/Erson Cams offers multi-groove heat-treated valve locks for maximum load carrying capacity and durability. These are ideal for moderate competition applications where ultra high spring pressues are not used and valve float is minimized.

Timing Chain Sets
In 289, 302, and 351W engines, Ford periodically redesigned the arrangement of the cam gear, cam spacer, fuel pump eccentric, and front cover clearance. Always check these items for interference problems. Erson/PBM offers quality gear drives and timing chains.

Dowel Pins
1972-earlier 289, 302, and 351W featured cams with dowell pins of two different lengths. Dowell pins measuring 1.375” extended through the 1-piece fuel pump eccentric. 1973-later engines featured a 2-piece fuel pump eccentric, which required the shorter 1.125” dowell pins. If the fuel pump eccentric is removed from the engine, use a thicker-than-stock retaining washer to take up the space lost by the eccentric.

A common failure on Ford engines is the shearing of dowell pins. The bolt in the center of the cam sometimes comes loose and allows the dowel pin to be loaded in shear. To help prevent dowel pin shearing, use a suitable thread locker on the center bolt and torque to the manufacturer’s recommended torque specifications.

Valve Springs
Because Ford Motor Co. has so many different engine families and so many different horsepower ratings within each family, the issue of valve spring selection becomes complex. However, the basic rule is application and area of installation. Whether you are setting up a stock cylinder head or an all out competition Ford SVO cylinder head the rule applies at both ends of the spectrum. The following chart is comprised of common Ford installed heights.

FordSpringChart.jpg


Camshafts
Camshafts for 289-302 Ford small block engines are exactly the same dimensionally as the 302 HO and 351W engines. This means one can be used in the other’s block but the firing order between the two engines are different for performance as well as structural reasons. The Ford early 289 and 302 non-HO engines have a 1,5,4,2,6,3,7,8 firing order and the late model 302 HO and 351W engines have a 1,3,7,2,6,5,4,8 firing order. The early Ford 289-302 engines are identified by our 210 prefix and the late model 302 HO and 351W engines are identified by the 212 prefix. It is possible to put a hydraulic roller camshaft in an early pre-1985 block. However, the following must be considered. This conversion requires the use of a small base circle camshaft which properly positions the taller hydraulic roller lifters in a non-hydraulic roller block. The block must be modified to accept stock Ford hydraulic roller lifter retention hardware and the use of an aluminum bronze distributor gear becomes mandatory. Due to the use of dissimilar alloys in this area longevity becomes a concern. These types of applications are special order items and can be ordered through Erson’s Special Order Department.

All camshafts produced by Erson Cams for the early 289-302 engine and the 302 HO and 351W engine will be manufactured and ground on standard OEM journal diameter cores. For camshaft cores with larger than stock diameters, i.e.: race blocks or roller bearing blocks, camshafts should be ordered from Erson’s Special Orders Department and are subject to billet availability.

1958-63 Ford FE engines used a camshaft with a flanged front bearing and a spring loaded thrust button. The flanged camshaft billets are no longer available. 1963 1/2 later camshaft cores will replace the earlier cams. For information regarding this conversion, contact Erson Cam’s Technical Service Team at 775.246.4062.

Hydraulic Roller Cams
You can use conventional hydraulic and solid lifter cams with Ford engines that come stock with hydraulic roller cams. However, you must also change the lifters, pushrods, valve springs, and rocker arms to accommodate the cam change. Essential Information for “FE” Engines 1958 through mid-1963 engines used a cam with a flanged front bearing and a spring loaded thrust button. The flanged cam billets are no longer available. 1963 1/2 and later type cams will replace the earlier cams. If you have the early engine, you must remove the soft plugs from the oil galleys on either side of the front cam bearing and tap the holes to 7/16 NC. Purchase cam bolt 304815-S and 2 washers. 34808-S and 44730-S8, and pump eccentric C3AZ6287A. The timing chain, crank, and cam sprockets must be changed to the later type. Some cam sprockets are manufactured with an integral spacer, purchase Ford spacer C3AZ6265A.

Do not, under any circumstances, use a common hardware bolt to hold the sprocket on the cam. Use only a Ford bolt. Use Loctite on the cam bolt and thrust plate bolts and torque to proper specs. When the cam is properly installed, it will rotate freely and will have approximately .010” end play. If any parts are omitted or substitutions made, the cam bolt may come loose or excessive end play may result. This could cause severe damage to the cam, tappets and engine. NOTE--Most American production engines cannot accept more than .500” lift without modifying the valve guides. When installing a cam with more than .500” lift, it is absolutely essential that clearance between the valve spring, retainer and guide be checked. Do not attempt to operate an engine with less than .150” retainer-to-guide clearance. If you are using valve seals, check the clearance from the top of the seal rather than the top of the guide. Firing Order--289-302 engines: 1-5-4-2-6-3-7-8 302 HO and 351W engines: 1-3-7-2-6-5-4-8

Solid Lifters
Because mechanical cams require lash adjustment, many production Ford heads will require machine work to run these cams, Ford engines with non-adjustable valvetrains must be converted to adjustable valvetrains to run solid lifter or mechanical camshafts.

Rocker Arm and Stud Combinations
Conventional stud mount adjustable rocker arms with pressed in studs were used on 1962-66 1/2 221, 260 CID engines and 289 high performance engines. A slot in the head or a guideplate aligns the rocker arm over the valve stem in the absence of rail type rockers. Guideplates are required when using Erson’s non-rail type rocker arms.

To convert early 1966 1/2- 68 standard 289, 1968-76 302-351W and 1968-72 429-460 engines equipped with positive stop stud non-adjustable rockers, the following steps must be taken. Convert by re-machining or replacing existing valve to valves equipped with .250” tip lengths, as opposed to OEM valves intended for use with rail type rockers using .395” valve tips. Remove the pressed in positive stop stud and machine the guideplate boss down .230”. Drill and tap using the appropriate hardware to accommodate a 7/16 x 14 bottomed stud. Install, using a brand name thread locker, the new fully adjustable stud through the guideplate and torque to 50 ft./lbs. Now, you are ready to install any roller tipped or full roller rocker arm. This combination will handle any hydraulic, hydraulic roller, mechanical flat tappet or street roller type camshaft.

1970-82 351C, 351M and 400 CID engines as well as 1973- 95 429-460 Ford engine were also equipped with nonadjustable valvetrains. These engines employed a nonadjustable rocker arm mounted on a slotted pedestal which slides on a “sled” fulcrum retained by a bolt as opposed to a stud. To convert to a fully adjustable valvetrain the same steps must be taken as in the previous paragraph. For milling instructions regarding these applications see accompanying illustration.

For 1972 and later 302 and 351W engines equipped with pedestal-mount fulcrum style stamped steel rockers, the same steps must be taken to install a fully adjustable stud. However, machining of the guideplate boss must begin at the top of the pedestal-mount(-) .230”. See illustration. For vehicles wishing to maintain pedestal-mount rockers, Erson/PBM offers full roller 1.6 and 1.7:1 billet rocker arms. Adjustment upwards is accomplished by shimming the stands to achieve the recommended .040” pre-load required for most hydraulic lifters. Adjustment downwards is accomplished by milling the stands or shorter pushrods.

NOTE: Pressed in studs of any type are not recommended for mechanical flat tappet camshafts with higher than 330 lbs. of pressure over the nose.

NOTE: Rail type rocker arms are intended for stock hydraulic camshafts only.

NECESSARY MODIFICATIONS FOR CYLINDER HEADS EQUIPPED WITH PEDESTAL-MOUNT NON-ADJUSTABLE ROCKER ARMS TO CONVERT TO FULLY ADJUSTABLE ROCKER ARMS.
NECESSARY MODIFICATION TO FULLY ADJUSTABLE VALVETRAINS

FordRockerImage.jpg


ILLUSTRATION DEPICTS TYPICAL FORD PEDESTRALMOUNT NON-ADJUSTABLE CYLINDER HEAD. NUMBERS REPRESENT PROPER MILLING DIMENSIONS TO ACCOMMODATE SCREW-IN STUD AND GUIDEPLATE ASSEMBLY. ENGINES EQUIPPED WITH POSITIVE STOP STUDS MACHINE DOWN FROM THE TOP OF THE STUD BOSS PERPENDICULAR TO THE EXISTING HOLE.
FordMillingImage.jpg


DO NOT MILL PARALLEL TO THE BOTTOM OF THE HEAD.

Rocker Arms 101:

There are three main styles of rocker arms used on small block ford heads. These include pedestal mount, stud mount, and shaft mount. I don't care what anyone tells you, none of them are just a bolt-on-and-go deal.

Pedestal Mount: Pedestal mount rocker arms are the type of rocker arm most commonly found factory installed on late model 5.0L engines. On most standard 5.0L engines, the rocker arms were plain old stamped steel. The 1993-1995 Cobra 5.0L engines received pedestal mount Crane 1.7 ratio roller rocker arms. All pedestal mount rocker arms are fastened to the cylinder head with a small 5/16" bolt. There are many performance pedestal mount rocker arms available, but of the three types of rocker arms, the pedestal mount is considered the weakest because it is held in place with the smallest fastener.

A couple examples of pedestal mount rocker arms:

Factory:
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1993-1995 Cobra/Crane 1.7 Ratio:
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Ford Racing:
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Pedestal Mount Installation Instructions: Only after you have ensured that you have the correct pushrod length, confirmed whether or not you need shims under the pedestals, that the rocker arm tip is centered on the valve stem tip, are you ready to install your pedestal mount rocker arms. One cylinder at a time, turn the motor over until that cylinder is at TDC on the compression stroke, and then slowly torque the rocker bolts for both rocker arms for that cylinder to 18-20/ft lbs. Pay attention to your torque wrench while you do this. You should be able to turn your torque wrench 1/4-1 full turn before it clicks at 18-20/ft lbs. If it clicks before 1/4 turn, or after 1 full turn, than you either have the wrong length pushrod or need to shim the pedestals and you need to figure out which before you start over.

For more comprehensive pedestal mount rocker arm instructions, please READ: http://cranecams.com/pdf/453e.pdf

Stud Mount: Stud mount rocker arms were factory installed on 1963-1968 Ford 289s, and early 302s any many other early engines. Most (not all) factory ford heads that came with studs were press in studs, which are not desirable for performance since those types of studs tend to pull out at high rpm with agressive cams and stiff valve springs. Screw-In Studs are the only type of stud used in performance aftermarket stud-mount heads. All small block ford 289/302 engines originally equipped with stud rockers had 3/8 studs. 3/8 referring to the section of the stud the rocker goes on. Studs commonly used in performance small block ford heads are available in either 3/8" or 7/16", both of which have a 7/16" thread that goes into the cylinder head's stud boss. Whenever you hear someone referring to a 3/8" or 7/16" stud, they are referring to the "top part" of the stud that the rocker arm goes on. The thicker the stud, the less prone they are to valvetrain flex. At high rpm, even studs can flex almost like trees in a windstorm. You can convert a head with 3/8" screw-in studs to 7/16" screw in studs without machining, but you will need different rocker arms since rocker arms are stud size specific, meaning you couldn't use a rocker arm for 3/8" studs on a 7/16" stud and vice versa. Stud mount rocker arms can be attached with a nylon lock nut or a poly lock. Poly locks are preffered because they are less likely to back the stud out of the head than nylon lock nuts are. If you have a really high revving motor, you can also tie all your studs together for increased stability with a stud girdle.

A couple examples of stud mount rocker arms/parts:

Factory:
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Screw In Rocker Studs:
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Comp Cams Magnum Roller Tip with Lock Nut:
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Crane Gold Race with Poly Lock:
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Stud Girdle:
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Stud Mount Installation Instructions: Stud mount rocker arms, just like any other rocker arm, require correctly measured pushrod length and correct valvetrain geometry. To install them, you need to turn the motor over by hand in the direction of engine rotation. With the intake off, you can watch the lifters. When the exhaust lifter for a particular cylinder just starts to come out of its bore, you can now adjust the intake rocker arm for that cylinder. Why? Because if the exhaust valve is just opening, the intake valve is closed and on the base circle of the cam, where we need it to be to adjust it. After you've adjusted the intake valve, keep turning the motor over by hand and watch the intake lifter, once the intake lifter has come as far out of its bore as it can (max lift) and then starts going back down, pay attention. When the intake lifter reaches 1/2 way to 2/3 of the way back down, you can stop and adjust the exhaust rocker. The typical adjustment procedure is to spin the pushrod in your fingers as you tighten the rocker, when you start to feel resistance on the pushrod, the slack has been taken out of the pushrod and you are at zero lash. Make a 1/2-3/4 further of a turn on the lock nut or poly lock once you have done this (if using a poly lock, don't forget to tighten the allen head screw).

For more comprehensive instruction, please READ: http://compcams.com/Technical/Instructions/Files/151.pdf

Shaft Mount: Shaft mount rocker arms are by far the most expensive type of rocker arms you can buy, and were never factory equipment on 289/302 based small block fords. There are a number of aftermarket manufacturers that make shaft mount rocker kits for popular small block ford heads, such as the Trick Flow Twisted Wedge, AFR 165/185/205/225, etc. They are the absolute best for valvetrain stability because they tie the rocker arm bodies together, and are even more stable than a stud girdle setup. The stands that the shaft mount rocker arms ride on are fastened to the cylinder head stud bosses where the rocker studs used to be, and the shaft mount rocker arms are then fastened to the stand. For extremely high revving race motor with only the best parts, there is no substitute for a shaft mount setup. Consider this: most factory muscle cars with big block engines, such as the Ford FE, Hemi, etc. came from the factory with shaft mount rocker arms. Shaft mount rocker arms for SBF's are available from Crane, Jesel, Comp, Harland Sharp, and others.

A couple examples of stud mount rocker arms:

Crane Shaft Mount:
craneSportsman.jpg



Jesel Shaft Mount:
new_products_ss_shaft_rocker.jpg



Shaft Mount Installation Instructions: Just like with any other rocker system, you need to check to see if the rocker stand that the shaft rockers are mounted to need to be shimmed, and you also need to measure for proper pushrod length. The installation procedure is essentially identical to stud mount rocker arms, in that you turn the motor over by hand and adjust each rocker arm when its cam lobe is on the base circle. You also have a lash adjuster on the top of the rocker arm body that works in a semi-similar fashion to a poly lock that you would normally find on a stud mount rocker arm.

An example of Shaft Mount Installation Instructions: http://www.jeselonline.com/docs/instructions/INS-SS0051.pdf
 
Hi grumpy,
thanks!! Does these spacers in combination with the high strength adjusting nuts allow me the adjustment? Theres is nothing more to do?
Is it necessary in combination with the cam?
Thanks Martin
 
https://www.summitracing.com/parts/...MIiqTDqfmC5QIVDNvACh3M4AUbEAQYASABEgJLUfD_BwE

very few things are simple
you need the correct matching adjustable rocker studs (they come in 3/8" and 7/16") and the stud bosses need to be machined

NECESSARY MODIFICATIONS FOR CYLINDER HEADS EQUIPPED WITH PEDESTAL-MOUNT NON-ADJUSTABLE ROCKER ARMS TO CONVERT TO FULLY ADJUSTABLE ROCKER ARMS.
NECESSARY MODIFICATION TO FULLY ADJUSTABLE VALVETRAINS

FordRockerImage.jpg


ILLUSTRATION DEPICTS TYPICAL FORD PEDESTRALMOUNT NON-ADJUSTABLE CYLINDER HEAD. NUMBERS REPRESENT PROPER MILLING DIMENSIONS TO ACCOMMODATE SCREW-IN STUD AND GUIDEPLATE ASSEMBLY. ENGINES EQUIPPED WITH POSITIVE STOP STUDS MACHINE DOWN FROM THE TOP OF THE STUD BOSS PERPENDICULAR TO THE EXISTING HOLE.
FordMillingImage.jpg


DO NOT MILL PARALLEL TO THE BOTTOM OF THE HEAD.
 
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once your familiar with basic engine performance builds you rapidly come to accept that with very few exceptions,
almost anything you might want to do to increase power will require both cash outlay and machine work,
and very few things you might want to do will be accomplished without the help of a skilled machinist and at least partial dis-assembly and re-assembly.
yes there are mods to the lubrication, headers, exhaust, and cooling and ignition systems,
and porting on the cylinder heads and intake manifolds, changes in valve train rocker ratios, etc.
but it takes the personal experience or at least research into what will work best in any particular project as every application has its potential strong or weak points.
In my opinion, few BRANDS and obsessive brand loyalty is rather misplaced as most manufacturers have produced both impressive designs and made some obvious mistakes.
and of course things change constantly, and access to parts is mostly dictated by what sells best in the market, and that is mostly linked to the numbers of the specific engine family that were sold.
manufacturers are reluctant to tool up for a limited market, regardless of how effective the part they might make might be.
you don,t see nearly as many BUICK, CADILLAC, PONTIAC AMC,or OLDS performance parts simply because, the market is very limited , for some engines and transmission combos,
compared to some of the more common chevy and ford engine families.
all the manufacturers produced decent engine combos and some less than impressive products.
the key is in doing the research before you start opening your wallet in a bottomless pit, hoping to improve your cars performance.
and in many cases you would be well advised to start with a vastly different car or engine,
as its rather easy to find your throwing cash into beating a dead horse as the saying goes.
yeah, do your research, theres not a thing wrong with deciding to build a 302 ford, 351 Cleveland or 427-, 428, FE, or 429,460 ford all have advantages but do your research carefully
 
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Hi Grumpy,
Thanks a lot. Here in germany you can't find some true Ford engine experts. I have to research and plan the most things by myself. I study and communicate about the net and the forums...like here and you. Its very helpful!!
My engine ist still assembled. Its a 347 stroker. new bored/drilled to the first oversize. I believe 0,30.
In my shelf I have a pair of Flow Tek heads. I plan to install it next spring.
But till spring I drive the car with the stock iron cast heads as described.
Thanks Martin
 
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