Swapping rocker studs - Need more length?

Loeryder

New member
Thats not what she said.... :lol:

Anywho, I am swapping out my rocker studs for a set of ARP studs and Crane 1.6 rollers.
Setup is L35 heads, valves are stock with LT1 hi rev springs, push rods are stock length.

Problem is I am only getting a few threads on the polylocks before they tighten.

Should the studs have a spacer/washer between the stud and the head to gain more height?
or should I say can I put one in there to get myself a couple more threads for peace of mind sake. :tup:
 
Last edited:
Re: Swapping rocker studs - Need more length?

I was under the impression that we need to use the 1.5's or modify the head. You also may need guide plates which will space them a little. I'm also learning this $hit in the last week of wrencing before nats.

Don't mean to HI-JACK the thread but..... If I get a working replacement set you can borrow my current set-up to at least have a running truck at NATS if you need them. But I guess you still have the stock set-up on hand too.

I'm heading out to buy a set of rockers and pushrods later today and I need quick info. I'm trying to solve a knock issue.
This may be common knowlege for most of you guys but with L-35's can I use any 1.5 / 3/8 rocker and rod for a Chevy Small Block? I already have adjustable studs and guide plates.

I'm looking at these from JEGS... and others that I may be able to get locally.
http://www.jegs.com/webapp/wcs/stores/servlet/CategoryDisplay?lang=-1&catalogId=10002&storeId=10001&categoryId=21003&searchItemId=73397
555-20100.jpg
 

JSM

Active member
Re: Swapping rocker studs - Need more length?

You either need self aligning rockers or guide plates and non self aligning rockers NOT both.
 

dgoodhue

BuSTeD 4.3
Re: Swapping rocker studs - Need more length?

SonomaGTlover said:
I was under the impression that we need to use the 1.5's or modify the head. You also may need guide plates which will space them a little. I'm also learning this $hit in the last week of wrencing before nats.

Don't mean to HI-JACK the thread but..... If I get a working replacement set you can borrow my current set-up to at least have a running truck at NATS if you need them. But I guess you still have the stock set-up on hand too.

I'm heading out to buy a set of rockers and pushrods later today and I need quick info. I'm trying to solve a knock issue.
This may be common knowlege for most of you guys but with L-35's can I use any 1.5 / 3/8 rocker and rod for a Chevy Small Block? I already have adjustable studs and guide plates.

I'm looking at these from JEGS... and others that I may be able to get locally.
http://www.jegs.com/webapp/wcs/stores/servlet/CategoryDisplay?lang=-1&catalogId=10002&storeId=10001&categoryId=21003&searchItemId=73397
555-20100.jpg

You can use 1.6 Rockers on the stock or L35 heads as long as the springs aren't binding and the the lift isn't too high (I think .480 and the valve guides need to be machined) If you have a stock cam/valve train you are all set. You can use SBC rockers, but you have to make sure that mixed and match setups (non self aligning vs self aligning), the stock valve train is self aligning rockers (Some L35's may have alignment plates from the factory, these are not guides plates).

For non self aligning rocker you need valve guide plates & hard pushrods (the stock pushrods will not work)

You can not use guide plates with self aligning rockers.

For most SyTy I would just use self Aligning, the guides plates add some high rpm stability but most of us don't have high rpm motors.
 

MikeRenz

not stock
Re: Swapping rocker studs - Need more length?

your stud prolly has too much girth and they probably can't penetrate the rockers deep enough to push the threads through up top to get a nut on

:lol:
 
Re: Swapping rocker studs - Need more length?

dgoodhue said:
For non self aligning rocker you need valve guide plates & hard pushrods (the stock pushrods will not work)
This may be my problem. They are definately guide plates but the rockers/rods appear to be stock, I'm not sure. The studs were converted over to adjustable so I may have a mixed set-up. Damn I hate not knowing what internals I have. I don't have a clue who built this engine.

You can not use guide plates with self aligning rockers.
This I knew but don't know how to tell the difference in self aligning and non self aligning. Maybe these pics can help?

PS...sorry Jas for the hijack, hope this is helping you too.

rocker1.jpg


rocker2.jpg
 

JSM

Active member
Re: Swapping rocker studs - Need more length?

Hard to tell from that picture. Does the tip of the rocker, hug the sides of the tip of the valve, or is the surface that touches the valve flat?
 

dgoodhue

BuSTeD 4.3
Re: Swapping rocker studs - Need more length?

I agree with JS, its hard to tell from the picture. I would need a picture of the other side of the rockers, basically the self aligning rockers are aligned by the top of the valve via a notch in the rocker. The pushrods if they have a few miles on them, would show wear if they weren't hardened.
 
Re: Swapping rocker studs - Need more length?

I'll have to take it all back apart again to see, but at least I know what to look for now. If I buy the new ones then I guess I don't have to worry about it, I'll just be sure to get the hard push rods and non self aligning rockers since I already have the guide plates in there.

With the higher RPM the self aligning rockers (if that's what they are) may be causing the rods to hit the guide plates (I noticed some were pretty close) hence my knock source. Damn, I hate to spend $300-$400 on these parts and still have knock but I am 99% certain that the valve train is the culprit. I guess we'll see huh?
 

Loeryder

New member
Re: Swapping rocker studs - Need more length?

I have the Crane gold self aligning.

Not sure what studs they are as these came out of another 4.3L V6 that was running these same rockers.

My original question still stands, can I use a washer to space my studs up higher to get an extra couple of threads?

I know that you need to use guideplates with non self aligning rockers, which is why I went with a self aligning setup. In that scenario the guideplate would act as a spacer between the stud and the head. So i SHOULD be able to use a hardened washer in place of a guideplate to get the extra length I need.

I turned the motor over by hand multiple times to make sure the lifters were bottomed out and the valve was fully seated before counting threads.
 

JSM

Active member
Re: Swapping rocker studs - Need more length?

I suspect you really need longer studs with those rockers. I would be afraid if you space them, you won't have enough engagement into the head and pull them out on that end. Lots of forces go on in the valve train.
 

dgoodhue

BuSTeD 4.3
Re: Swapping rocker studs - Need more length?

You may have to check you pushrod length as well if you have a spacer.
 

JSM

Active member
Re: Swapping rocker studs - Need more length?

Yep, the rocker should be riding in the center of the valve. If it doesn't then you will have high valve guide wear and need to replace/repair heads soon.

Valve train is a very complicated system to get RIGHT. Changing 1 item can throw all kinds of things off as you have found.
 

MikeRenz

not stock
Re: Swapping rocker studs - Need more length?

Loeryder said:
My original question still stands, can I use a washer to space my studs up higher to get an extra couple of threads?
No. The neck of the stud, just past the thread...is too thick for the rocker to sit down any further. You'll never get more stock threads through the rocker.
 

RSpengler

Ghetto Fab Specialist.
Re: Swapping rocker studs - Need more length?

I had to put washers under my ARP conversion studs when I did my Vortec swap to get the proper height for my Crane Gold 1.5's (self aligning).

I haven't had any problems with them pulling out or not having enough bite. <shrug>
-Rob
 

Loeryder

New member
Re: Swapping rocker studs - Need more length?

Well since I dont know what is in there I am kind of guessing, but looking over the available studs from ARP they have different "effective stud length" measurements.

I am going to measure mine tonight, but the studs on summit range from:
1.9 - 2.230 - 2.348

Also, I am not sure what the threads in the head and my locks are.
Anyone know if it is in fact a 3/8-16 or 3/8-24 in the head?

I will probably end up using hardened washers for the Nats and buy the longer studs when I get back.
The clock is ticking here....
 

JSM

Active member
Re: Swapping rocker studs - Need more length?

If they are stock heads and thread they are probably metric threads.
 

MikeRenz

not stock
Re: Swapping rocker studs - Need more length?

no washers. And a slightly longer collar so the threads protrude through the rocker
 
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