Lifter question?
Thread Starter
Joined: Aug 2005
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From: Greenville PA
Lifter question? What should I be looking for? Figured heads were off, screwed everything else up on cam install, was hoping I spared the lifters. Yes I'm sure I could have looked in the archives for this answer but wanted some fresh answers on this subject. Thanx. 
I am in currently in the process of doing a head/cam upgrade. I am going with Morel lifters. They seem to get the best feedback but they cost around $450. My second choice would be Comp R lifters.
TECH Senior Member
Joined: Mar 2004
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From: BFE
Originally Posted by 777
I would just get some stock replacement lifters. There is no need to spend 450 when you can spend 200 and be fine.
Comp 850-16 are plenty and cheaper than OEM ones
On The Tree
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Originally Posted by TA BOY
If U Buy The Comp R Lifters Do U Need To Buy Adjustable Rookers?
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TECH Senior Member
Joined: Mar 2004
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From: BFE
Originally Posted by LS1 Swapper
No, I'm running Comp R's with ~0.060" preload cold with stock rockers, works just fine. Seems to be a good deal of misconception about hydraulic lifters and preload on this board. Really not sure what is up with Comp and their preload specs.
Comp "R" have to be .0080>.010 cold, perhaps you have 16 different length custom push rods?
Last edited by PREDATOR-Z; Sep 7, 2005 at 12:05 PM.
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Verdad Gallardo TECH Senior Member
Joined: Mar 2004
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From: BFE
I've used them, yes, and they need adjustable rockers.
Unless you do not know that, lifter preload will not be equal on all of them.
With non adjustable rockers, you'll need custom p-rods of various length to achieve equality.
Comp "R" are not forgiving as other hydraulic lifters when it comes to tolerances, as a matter of fact, I would never even set preload on these cold.
Unless you do not know that, lifter preload will not be equal on all of them.
With non adjustable rockers, you'll need custom p-rods of various length to achieve equality.
Comp "R" are not forgiving as other hydraulic lifters when it comes to tolerances, as a matter of fact, I would never even set preload on these cold.
Originally Posted by PREDATOR-Z
I've used them, yes, and they need adjustable rockers.
Unless you do not know that, lifter preload will not be equal on all of them.
With non adjustable rockers, you'll need custom p-rods of various length to achieve equality.
Comp "R" are not forgiving as other hydraulic lifters when it comes to tolerances, as a matter of fact, I would never even set preload on these cold.
Unless you do not know that, lifter preload will not be equal on all of them.
With non adjustable rockers, you'll need custom p-rods of various length to achieve equality.
Comp "R" are not forgiving as other hydraulic lifters when it comes to tolerances, as a matter of fact, I would never even set preload on these cold.
On The Tree
Joined: Jan 2004
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Originally Posted by PREDATOR-Z
I've used them, yes, and they need adjustable rockers.
Unless you do not know that, lifter preload will not be equal on all of them.
With non adjustable rockers, you'll need custom p-rods of various length to achieve equality.
Comp "R" are not forgiving as other hydraulic lifters when it comes to tolerances, as a matter of fact, I would never even set preload on these cold.
Unless you do not know that, lifter preload will not be equal on all of them.
With non adjustable rockers, you'll need custom p-rods of various length to achieve equality.
Comp "R" are not forgiving as other hydraulic lifters when it comes to tolerances, as a matter of fact, I would never even set preload on these cold.
What would the effect of say one preload being 0.055" and the next being 0.065"?
And why would you never set them cold?
Again misconceptions on forums
Originally Posted by LS1 Swapper
Tell me what is so special about these hydraulic lifters that they need a precise preload? and why would 0.040 or 0.050 or 0.060 be bad compared to 0.080-0.100?(which would be easy to achieve without adjustable rockers, but I guess they NEED them...)
What would the effect of say one preload being 0.055" and the next being 0.065"?
And why would you never set them cold?
Again misconceptions on forums
What would the effect of say one preload being 0.055" and the next being 0.065"?
And why would you never set them cold?
Again misconceptions on forums
Not trying to pick a fight, but when I decided on Comp "R's" I also had to complete the package to support them.
On The Tree
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Originally Posted by Lasershop
According to Comp... R series lifter preload is .003 to .005. I would imagine it takes some serious time to achieve that kind of tolerance. I suppose the motor might actually run with the valves hanging open 50, 60 eighty thou' or so........
Not trying to pick a fight, but when I decided on Comp "R's" I also had to complete the package to support them.
Not trying to pick a fight, but when I decided on Comp "R's" I also had to complete the package to support them.
It's not going to hang your valve open unless you bottom out the lifter with too much preload, the spring in the lifter is no match for the valve spring.
TECH Senior Member
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From: BFE
I edited my post as i noticed I made a typo on preload setting it is .008>.010 cold.
.060 preload is way too much and the lifter will collapse if set that much upon pump up.
If you do not believe this, then call someone who builds LSx and uses them frequently.
Originally Posted by LS1 Swapper
No, I'm running Comp R's with ~0.060" preload cold with stock rockers, works just fine. Seems to be a good deal of misconception about hydraulic lifters and preload on this board. Really not sure what is up with Comp and their preload specs.
from a reputable sponsor builder.
The R's want .002-.004 preload at operating temps. Because the aluminum block and heads expand more under heat than the steel lifters and pushrods, hot preload will be less than cold preload by about .006 to .008. So if you set cold preload less than about .010, you run the risk of hot preload going to zero, which will cause lots of problems including plenty of valve noise and eventual failure.
The R's want .002-.004 preload at operating temps. Because the aluminum block and heads expand more under heat than the steel lifters and pushrods, hot preload will be less than cold preload by about .006 to .008. So if you set cold preload less than about .010, you run the risk of hot preload going to zero, which will cause lots of problems including plenty of valve noise and eventual failure.