Author Topic: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms  (Read 5753 times)

8T03S1425

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When setting adjustable rocker arms on an engine with an hydraulic flat tappet cam, should I remove the distributor to manually spin the oil pump in an attempt pump up, or maintain pressure within the hydraulic flat tappet lifter for the rocker arm being adjusted?

I’m otherwise okay with the process of adjusting the rocker arms and offer the following as a check and for a basis of general discussion.

When an engine has a stock, or a mildly modified cam, I’m told that adjusting the rocker arms for each cylinder at TDC is preferred. This is because there’s less chance of confusion, and at TDC both valves in that cylinder should be closed, meaning both lifters are on the heels of the camshaft.

I have also read about and used the EOIC method. Followers of the EOIC method believe this is a better method of determining that the rocker arm being adjusted has the associated lifter on the heel of the cam lobe, and minimizes errors due to variations in cam profiles for increased lift duration.

For those unfamiliar with the EOIC method, it may come across as being complicated or confusing, because you’re monitoring one valve’s motion and then adjusting the other valve. Additionally, as you work down a cylinder bank, you’ll need to pay attention to the pattern of exhaust and intake valves. FE heads have the valve pattern of E-I, E-I, I-E, I-E, whereas the 289, 302 & 351W heads have a valve pattern of E-I, E-I, E-I, E-I. Anyway, the EOIC method breaks down like this:

Pick a cylinder for the exhaust and intake valves you want to adjust.
Rotate the crankshaft until the Exhaust valve of that cylinder begins to Open.
Stop rotating the crankshaft and set the Intake valve to zero lash and then tighten an additional 1/2 turn*.
If you have a locking nut, you can snug it now.
Rotate the crankshaft until the Intake valve begins to Close.
Stop rotating the crankshaft and set the Exhaust valve to zero lash and then tighten an additional 1/2 turn*.
If you have a locking nut, you can snug it now.

*  Check with the cam or lifter manufacturer for this pre-load. I have read where some mechanics use additional pre-loads ranging between 1/2 turn and 1 full turn.

Steve
I have owned 8T03S-01425 since 06/76.
I owned 6S2295 in 1973 & ‘74.

shelbydoug

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #1 on: March 31, 2020, 04:06:02 PM »
Why are you using adjustables? Those are for solids. Use the stock, non-adjustable arms, bolt them down and forget about it.

There is NO advantage to using the adjustables. None.
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The Going Thing

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #2 on: March 31, 2020, 04:41:22 PM »
Well, that's not exactly true. I run adjustable too. There is about a .030 increase in lift with the 1.76 Vs 1.73 rocker ratio.  You do not want them pumped up at all.  You need to set your preload.  When I get home this evening I will find and post the article on adjustment. You don't need to do anything with the distributor what so ever other than removing the wires from the valve covers and laying them to the front of the heads. You'll need a remote starter switch and I suggest unplugging the wire power to the coil.  Anyway, I'll try and find the sheet when I get home, if not a link to the website.

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #3 on: March 31, 2020, 05:05:35 PM »
  Yes Doug ,
      "Some of us do run adjustables on hyd cams for the reason Keith stated . the amount of lift increase is .003 x the lobe lift so on a .300 lobe lift ( .519 gross at the valve) the rocker change would make the gross lift .528. The bigger the cam lobe , the more lift. On my 428 with a .342 lobe , I get .012 which gets me right at .600 lift. Big difference? Not that big and might not show up on an ET slip. I did it because my valve stem heights varied a bit and I like less preload as Keith mentioned.
     The average FE owner with a hydraulic cam doesn't need adjustables in reality  , I agree.
   Randy
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Royce Peterson

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #4 on: March 31, 2020, 05:49:01 PM »
The other really good reason for using adjustable rockers is that you can make up for differences caused by machining and non - factory head gaskets by simply adjusting the rocker arm. When heads get milled, blocks get decked, and you use some head gasket other than stock it can put the valve adjustment out of range of a stock non adjustable rocker and stock length ball / ball pushrod.

On the other hand the stock adjustable rockers are not known for being able to hold an adjustment for long when the adjuster has been used a few times. Of course there are first and second oversize adjusters to help compensate. There are also aftermarket set ups that use a lock nut to eliminate this issue.

I prefer the non - adjustables when I am able to control all the variables.
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The Going Thing

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #5 on: March 31, 2020, 07:00:43 PM »
Royce hit a point I missed while sitting in a class. The FEs are a funny animal, and with a cam change and geometry changes it almost always needs a custom pushrod length.  The adjustable rockers allow some compensation for small changes without having to go that route.
Anyway, I will look for the "cheat sheet" that works great for the KISS system for adjustment. I shall return!

8T03S1425

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #6 on: April 01, 2020, 12:21:06 AM »
Doug, Keith, Randy, and Royce, thank you for providing this technical guidance. I'm a hobbyist who's willingness to turn a wrench far exceeds my qualifications to do so. The good new is, my interest in high performance cars stimulates my desire to learn how to work on them. The bad news is, I all too often find that there is no such thing as a free education with on the job learning. I successfully adjusted valve lash on a 289 with solid lifters, after watching others do it. I never felt comfortable adjusting rocker arms for preload on an engine with hydraulic lifters, because none of my car guy buddies did it or showed me how.

Even though I could use a remote start switch to crank the engine, previous to asking for help, I decided to take out the spark plugs and spin the engine manually with a socket and ratchet on the harmonic balancer bolt. I did that because I thought it gave me more control on positioning the crank and cam shafts to determine when the lifters were on the heel of the cam. I removed the distributor because I thought that I needed to spin the oil pump to pump up the lifters. Now, if I understand your comments there is no need to pump up the lifters when I set rocker arm preload. And, I should adjust each rocker for zero lash and then add another 1/2 turn for preload. Zero lash is when the rocker arm adjuster applies enough pressure that spinning the push rod starts to become difficult.

Regarding why I'm using adjustable rocker arms...

In 1977, I needed to replace my original engine. I purchased a 428CJ that was pulled from a '69 Torino Cobra. I disassembled the engine and took the parts to Shaw's Speed Shop. The store's manager was more than willing, and I thought helpful, to make recommendations on how I should spend my money rebuilding the engine. Besides the typical procedures, i.e., hot tank cleaning, magnaflux, cam bearing insertion, bore and hone of the cylinders, I had the block decks paralleled and the block align bored.

When we talked about cam selection, I went with his recommendation for a Crane "Fireball" 34434 and hydraulic lifters. He also recommended that I replace the stock rocker arms with Crane adjustable rockers, with locking nuts, and the associated ball & cup push rods. After reading your comments, I was reminded of his reasons for going with adjustable rocker arms. So I feel better about his rationale for the recommendation.

The engine ran fine for a while but had a right side valve tap that I couldn't quiet even though I adjusted the loose rocker arms a couple of times. While checking the fluids after a day out on the road, I saw that my coolant and oil looked like a black and white milk shake.

That was back in the early '80s. I parked the car and pulled the engine, intending to rebuild it. Well, life events interfered and it wasn't until some 20+ years later later that I could do something about it. Incidentally, I was one of those guys that kept telling Domenic that the car wasn't for sale as I was intending to get to working it some day.

In 2007 I had a professional engine builder, Doug Meyers, rebuild my engine. He installed Crower cam 16243, the associated flat tappet hydraulic lifters, and push rods. He also reused my adjustable rocker arms.

Crower cam 16243, Grind #297HDP, is described as having:

     Intake duration 297 degrees, Lift .590"
     Exhaust duration 308 degrees, Lift .588"
     Based on a 1.76 rocker arm ratio, Intake & Exhaust

     The spec sheet doesn't provide an overlap spec, but provides information, "...for degreeing cam only. Correct only at 0.050" tappet lift.":
          Intake opens at 10 degrees BTDC and closes at 46 degrees ABDC.
          Exhaust opens at 57 degrees BBDC and closes at 5 degrees ATDC.

I can't really make hide nor hair of those specs, but I've included them in case they are important for this discussion.

The engine sat assembled on my engine stand until 2015 when I had my Shelby restored.

So, that's the whole story as to why I have adjustable rocker arms on an engine that uses an hydraulic flat tappet cam.

Any other tid bits of help you can provide will be greatly appreciated. I'd really like to get this engine running as it should, without having to pull it out.

Steve
I have owned 8T03S-01425 since 06/76.
I owned 6S2295 in 1973 & ‘74.

Royce Peterson

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #7 on: April 01, 2020, 09:03:15 AM »
If these are stock style adjustable rockers then you typically will need to replace all the adjusters with first oversize if you are needing to adjust them again. Otherwise they will come loose in no time and then you will get to do it again.

I learned a trick on adjusting hydraulic valves that is so simple it is ridiculous. But it works for me. I put a piece of masking tape on the valve cover sealing surface above the valves on each side the length of the engine. I rotate the engine until I get used to seeing how far each valve goes open before it starts coming back up. When I am comfortable knowing when a valve is full open, I can adjust the closed valve next to it. After adjustment I use a Sharpie to put an "X" above that valve so I know it has been adjusted.

Each valve is adjusted by running the adjustment out until there is play in the rocker arm. Use two fingers to feel and rotate the pushrod as you tighten the adjustment. When the pushrod cannot be turned with a thumb and forefinger you add 1/2 turn to the adjustment.

Eventually you will have an "X" next to each valve. Then you know you are done.


Doug, Keith, Randy, and Royce, thank you for providing this technical guidance. I'm a hobbyist who's willingness to turn a wrench far exceeds my qualifications to do so. The good new is, my interest in high performance cars stimulates my desire to learn how to work on them. The bad news is, I all too often find that there is no such thing as a free education with on the job learning. I successfully adjusted valve lash on a 289 with solid lifters, after watching others do it. I never felt comfortable adjusting rocker arms for preload on an engine with hydraulic lifters, because none of my car guy buddies did it or showed me how.

Even though I could use a remote start switch to crank the engine, previous to asking for help, I decided to take out the spark plugs and spin the engine manually with a socket and ratchet on the harmonic balancer bolt. I did that because I thought it gave me more control on positioning the crank and cam shafts to determine when the lifters were on the heel of the cam. I removed the distributor because I thought that I needed to spin the oil pump to pump up the lifters. Now, if I understand your comments there is no need to pump up the lifters when I set rocker arm preload. And, I should adjust each rocker for zero lash and then add another 1/2 turn for preload. Zero lash is when the rocker arm adjuster applies enough pressure that spinning the push rod starts to become difficult.

Regarding why I'm using adjustable rocker arms...

In 1977, I needed to replace my original engine. I purchased a 428CJ that was pulled from a '69 Torino Cobra. I disassembled the engine and took the parts to Shaw's Speed Shop. The store's manager was more than willing, and I thought helpful, to make recommendations on how I should spend my money rebuilding the engine. Besides the typical procedures, i.e., hot tank cleaning, magnaflux, cam bearing insertion, bore and hone of the cylinders, I had the block decks paralleled and the block align bored.

When we talked about cam selection, I went with his recommendation for a Crane "Fireball" 34434 and hydraulic lifters. He also recommended that I replace the stock rocker arms with Crane adjustable rockers, with locking nuts, and the associated ball & cup push rods. After reading your comments, I was reminded of his reasons for going with adjustable rocker arms. So I feel better about his rationale for the recommendation.

The engine ran fine for a while but had a right side valve tap that I couldn't quiet even though I adjusted the loose rocker arms a couple of times. While checking the fluids after a day out on the road, I saw that my coolant and oil looked like a black and white milk shake.

That was back in the early '80s. I parked the car and pulled the engine, intending to rebuild it. Well, life events interfered and it wasn't until some 20+ years later later that I could do something about it. Incidentally, I was one of those guys that kept telling Domenic that the car wasn't for sale as I was intending to get to working it some day.

In 2007 I had a professional engine builder, Doug Meyers, rebuild my engine. He installed Crower cam 16243, the associated flat tappet hydraulic lifters, and push rods. He also reused my adjustable rocker arms.

Crower cam 16243, Grind #297HDP, is described as having:

     Intake duration 297 degrees, Lift .590"
     Exhaust duration 308 degrees, Lift .588"
     Based on a 1.76 rocker arm ratio, Intake & Exhaust

     The spec sheet doesn't provide an overlap spec, but provides information, "...for degreeing cam only. Correct only at 0.050" tappet lift.":
          Intake opens at 10 degrees BTDC and closes at 46 degrees ABDC.
          Exhaust opens at 57 degrees BBDC and closes at 5 degrees ATDC.

I can't really make hide nor hair of those specs, but I've included them in case they are important for this discussion.

The engine sat assembled on my engine stand until 2015 when I had my Shelby restored.

So, that's the whole story as to why I have adjustable rocker arms on an engine that uses an hydraulic flat tappet cam.

Any other tid bits of help you can provide will be greatly appreciated. I'd really like to get this engine running as it should, without having to pull it out.

Steve
1968 Cougar XR-7 GT-E 427 Side Oiler C6 3.50 Detroit Locker
1968 1/2 Cougar XR-7 428CJ Ram Air C6 3.91 Traction Lock

68stangcjfb

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #8 on: April 01, 2020, 12:37:06 PM »
When I adjust valves, I bring the number one cylinder to top dead center on the compression stroke. O degrees on the pointer. I then put a chalk mark or piece of tape at the very top of the damper or the lower pulley. I adjust the valves on #1 cylinder. I then rotate the crankshaft 1 quarter turn and then adjust the valves on the next cylinder in the firing order. Each quarter turn you turn the engine brings the next cylinder in the firing order to TDC until you've turned the engine 2 full turns. You end up back at number one cylinder and you're done. 30 years ago, when I was bending pushrods on my Fairlane for no apparent reason, this was the quickest way to run the valves when I got stuck on the street and had to change them out on the road. Of course I know now why they were bending. .587 lift Crane cam, Sidewinder intake & the holes in the intake not big enough causing the pushrods to contact the intake manifold. At 6000 RPM, the pushrods didn't like that very much!😵 Be sure to check that when you assemble your engine.
« Last Edit: April 01, 2020, 12:39:16 PM by 68stangcjfb »
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gt350hr

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #9 on: April 01, 2020, 12:40:49 PM »
   Steve,
      Doug Meyers is a great machinist/engine builder , long time Shelby owner and personal friend of mine for over twenty years. The cam he picked for you is 236* duration @ .050 on the intake and 242 on the exhaust. That is an excellent ''step up" over a CJ cam. Because of the nature of this aftermarket cam , I suggest using the Exh just opening - set the intake and Int begining to close set exh. That way you can be certain the lifter is on the base circle. Because it is a more aggressive aftermarket cam , you could use a 1/4 to 1/2 turn preload and be safe . "I" use 1/4 turn and a similar hyd cam in my 428.
   Randy
Celebrating 46 years of drag racing 6S477 and no end in sight.

The Going Thing

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #10 on: April 01, 2020, 01:03:19 PM »
I have a write-up about base circle adjustment. The way Ford tells you to do it for factory cams does not work with a cam with performance cam of this nature. If you're assembling the engine it's even easier when you can see what the lifter is doing. I have a couple of tasks to complete and I will try and get it posted for you. It really does simply adjustment so you'll get it right the first time. We have very similar cams, but I decided to run my cam with roller rockers.

pbf777

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #11 on: April 01, 2020, 01:22:01 PM »

Even though I could use a remote start switch to crank the engine, previous to asking for help, I decided to take out the spark plugs and spin the engine manually with a socket and ratchet on the harmonic balancer bolt. I did that because I thought it gave me more control on positioning the crank and cam shafts to determine when the lifters were on the heel of the cam. I removed the distributor because I thought that I needed to spin the oil pump to pump up the lifters. Now, if I understand your comments there is no need to pump up the lifters when I set rocker arm preload. And, I should adjust each rocker for zero lash and then add another 1/2 turn for preload. Zero lash is when the rocker arm adjuster applies enough pressure that spinning the push rod starts to become difficult.


     Agreed, best procedure, remove the plugs, turn by hand. 

     No need to pump-up the lifters, as a mater choice I prefer them bled-down for better feel, but that's me. 

     Generally, the suggested sum of .020" - .040" "lifter-punger-preload" is that which one is targeting, if the adjusting ball stud in the rocker is 3/8" x 24 tread per inch, then 1/2 turn equals just over .020".   But less is often chosen by racers who will maintenance this more frequently.

Quote
He also recommended that I replace the stock rocker arms with Crane adjustable rockers, with locking nuts, and the associated ball & cup push rods. After reading your comments, I was reminded of his reasons for going with adjustable rocker arms. So I feel better about his rationale for the recommendation.

In 2007 I had a professional engine builder, Doug Meyers, rebuild my engine. He installed Crower cam 16243, the associated flat tappet hydraulic lifters, and push rods. He also reused my adjustable rocker arms.
 
So, that's the whole story as to why I have adjustable rocker arms on an engine that uses an hydraulic flat tappet cam.




      I would consider it to have been a good choice to use the Crane rocker arms in your build, and prefer them particularly, but even O.E.M. adjustable versus the nonadjustable rockers even in hydraulic camshaft applications whenever possible for a number of reasons.

      And as one consideration for the naysayers, consider the scenario if you were to try adjusting for the lash value of a mechanical camshaft on the FE, using nonadjustable rockers, by only shimming up or down under the four rocker stands (equally)?  Although I agree that perhaps the lash value of the mechanical camshaft is more critical then the lifter plunger preload value, but perhaps just the thought of the reasons why it wouldn't work (well ideally anyway) is what will spark the understanding of the preference for the possibility of individual setting of each versus an averaging of the whole.  It may only prove to be a question of how accurate do you want to be?            :-\

      And, it would be better to use the E.O.I.C. process in adjusting with the more aggressive after market camshafts.    ;)

      Scott.       
« Last Edit: April 01, 2020, 03:11:06 PM by pbf777 »

The Going Thing

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #12 on: April 01, 2020, 01:52:48 PM »
You don't want to run Crane Rollers. They're poorly made. The are known for bore wear and breakage. Not just my opinion, but many on the FE forum.  A good reasonable unit is from Doug at Precision Oil Pumps. You'll want to run the stud kit as well and the end stands and end supports and shafts.  The cam you're running will not work with stock springs or pressures.   The seat pressure for that cam is about 135lb on the seat and should be about 335 open. The factory rocker shafts aren't designed for those loads and you're asking for a failure.
Either way, roller or non-roller you'll need the stands, shafts, studs and end supports.
If you ran single factory springs you'll have to pull the heads and have them set up. You can't run a .600 lift cam on stock single springs, retainers and unmachined guides. You'll have coil bind and wind up bottoming the spring retaines on the guide.



http://stores.precisionoilpumps.com/fe-ford-billet-end-support-stands/
http://stores.precisionoilpumps.com/fe-ford-hd-chrome-moly-rocker-arm-shafts/
http://stores.precisionoilpumps.com/fe-ford-roller-rocker-arms/
http://stores.precisionoilpumps.com/ford-fe-390-427-low-riser-428-cj-billet-rocker-stands/
http://stores.precisionoilpumps.com/ford-fe-390-428cj-427lr-rocker-stud-kit/



« Last Edit: April 01, 2020, 10:27:19 PM by The Going Thing »

8T03S1425

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #13 on: April 01, 2020, 10:07:57 PM »
   Steve,
      Doug Meyers is a great machinist/engine builder , long time Shelby owner and personal friend of mine for over twenty years. The cam he picked for you is 236* duration @ .050 on the intake and 242 on the exhaust. That is an excellent ''step up" over a CJ cam. Because of the nature of this aftermarket cam , I suggest using the Exh just opening - set the intake and Int begining to close set exh. That way you can be certain the lifter is on the base circle. Because it is a more aggressive aftermarket cam , you could use a 1/4 to 1/2 turn preload and be safe . "I" use 1/4 turn and a similar hyd cam in my 428.
   Randy

Thanks for confirming that using the EOIC method of setting lifter preload for this cam setup. I'll put some effort in it tomorrow. I had to walk away from it as I've been more susceptible to repair related frustrations lately.

Doug is a good guy. I'm glad I found him and he's very close to where I live. He's a pleasure to talk with, not shy about giving me a tour of his shop when I drop off something to be worked on or ask to purchase something incidental, and someone who I'd describe as being a quiet achiever. I'm working on getting a date code correct short block and he'll be building a complete engine for me. He's already rebuilt the heads.

It's interesting that you described the cam he selected as an excellent ''step up" over a CJ cam, because that's exactly what I asked for. I wanted that and I wanted the engine to have a pleasant lump at idle. It does sound good at idle. That might sound a bit immature, but I think a moderate bit of immaturity is okay.  ;)

The next time I see him, I'll ask about his Shelby and tell him that Randy Gillis says hey.

Steve
I have owned 8T03S-01425 since 06/76.
I owned 6S2295 in 1973 & ‘74.

8T03S1425

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Re: 428 PI/CJ Hydraulic Flat Tappet Lifters w/Adjustable Rocker Arms
« Reply #14 on: April 01, 2020, 10:17:28 PM »
I have a write-up about base circle adjustment. The way Ford tells you to do it for factory cams does not work with a cam with performance cam of this nature. If you're assembling the engine it's even easier when you can see what the lifter is doing. I have a couple of tasks to complete and I will try and get it posted for you. It really does simply adjustment so you'll get it right the first time. We have very similar cams, but I decided to run my cam with roller rockers.

Thanks Keith. I'd love to see the write up.

I was considering roller rockers when I was having my engine built. Others also pointed me in that direction. I decided against using them because I was told that they may not fit under the Cobra LeMans valve covers, and using the Cobra LeMans valve covers was important to me. Are you able to use the Cobra LeMans valve covers with the roller rockers?

Steve
I have owned 8T03S-01425 since 06/76.
I owned 6S2295 in 1973 & ‘74.