Comp R lifter preload problem and very interesting solution proposed by Louis of LG
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Comp R lifter preload problem and very interesting solution proposed by Louis of LG
First off, I wanted to thank this board's sponsors for all the help they've given.
Nasty N8, AP Engineering, TEA, MTI, and LG have all been great help.
Well, here is my issue:
I have different preload on every lifter on every cylinder.....
Cylinder# Intake Preload/Exhaust Preload
1 .025/.046
3 .026/.047
5 .027/.048
7 .024/.049
2 .017/.032
4 .015/.033
6 .016/.034
8 .018/.035
I ended up ordering the Ford Shims in .015 and .030 sizes, but the problem I have is that my Yella Terras are attached on each cylinder, so for example, on cylinder 1 I can't use a .15 shim on the intake and a .30 shim on the exhaust because wouldn't that cause some sort of imbalance since they're connected?
LG suggested for example, using .30 shims on all the passenger side rockers, getting the preload to the following:
Cylinder# Intake Preload/Exhaust Preload
2 -.013/.002
4 -.015/.003
6 -.014/.004
8 -.012/.005
Then I would use lash caps on the top of the valve stems to get the preload back to where I'd like it to be since lash caps come in more sizes and offer more "adjustability" if you would.
Nasty N8, AP Engineering, TEA, MTI, and LG have all been great help.
Well, here is my issue:
I have different preload on every lifter on every cylinder.....
Cylinder# Intake Preload/Exhaust Preload
1 .025/.046
3 .026/.047
5 .027/.048
7 .024/.049
2 .017/.032
4 .015/.033
6 .016/.034
8 .018/.035
I ended up ordering the Ford Shims in .015 and .030 sizes, but the problem I have is that my Yella Terras are attached on each cylinder, so for example, on cylinder 1 I can't use a .15 shim on the intake and a .30 shim on the exhaust because wouldn't that cause some sort of imbalance since they're connected?
LG suggested for example, using .30 shims on all the passenger side rockers, getting the preload to the following:
Cylinder# Intake Preload/Exhaust Preload
2 -.013/.002
4 -.015/.003
6 -.014/.004
8 -.012/.005
Then I would use lash caps on the top of the valve stems to get the preload back to where I'd like it to be since lash caps come in more sizes and offer more "adjustability" if you would.
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Originally Posted by verbs
First off, I wanted to thank this board's sponsors for all the help they've given.
Nasty N8, AP Engineering, TEA, MTI, and LG have all been great help.
Well, here is my issue:
Nasty N8, AP Engineering, TEA, MTI, and LG have all been great help.
Well, here is my issue:
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#8
Originally Posted by Country Boy
Adjustable rockers are soooo much easier
If I were one of those shops listed I might have suggested.." hey why don't we set you up with a good set of Comp Pro Mag's"
#10
FormerVendor
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The only lash cap thinkness I know of is .060", you would have to grind them to yeild something different and would have to be done on something like a surface grinder to make sure they are flat. On another note, I believe factory lifters can be adjusted anywhere from a few thousandth's from the top of the plunger all the way to .015" from the bottom like LPE once reccommended. I contacted Comp and ask if there is any reason why these lifters can not be adjusted the same and the response I got was NO, meaning, the plunger can be put about anywhere in its travel just like a stock lifter and still works. I didn't shim my R at all with my Harland Sharp rockers, and never had a problem.
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Originally Posted by Brian Tooley
I contacted Comp and ask if there is any reason why these lifters can not be adjusted the same and the response I got was NO, meaning, the plunger can be put about anywhere in its travel just like a stock lifter and still works.
You're saying that Comp told you the .002-.004 preload is not critical? Not that I'm suprised, but I'd sure like to hear more about that.
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Originally Posted by Brian Tooley
I contacted Comp and ask if there is any reason why these lifters can not be adjusted the same and the response I got was NO, meaning, the plunger can be put about anywhere in its travel just like a stock lifter and still works. I didn't shim my R at all with my Harland Sharp rockers, and never had a problem.
So far I've seen feedback ranging from one extreme (installed them just like stockers and no issues) to the other (make sure preload is set just right or you'll end up with lifter parts all over your engine).
Which is it??
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Originally Posted by michael101
You're saying that Comp told you the .002-.004 preload is not critical? Not that I'm suprised, but I'd sure like to hear more about that.
LG runs their Comp R preload from .010-.020, and sometimes as high as .025. They say they've never had any problems running the comp R lifters like this. Running the preload on the comp R's below .010 will cause a lot of valvetrain noise too.
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Originally Posted by spectacle solutions
That's what I'm screaming!
If I were one of those shops listed I might have suggested.." hey why don't we set you up with a good set of Comp Pro Mag's"
If I were one of those shops listed I might have suggested.." hey why don't we set you up with a good set of Comp Pro Mag's"
Originally Posted by 66ImpalaLT1
Why is your head .010 shorter on the drivers side?
I was told they just took off a couple thousandths.
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verbs,
I'm new to this whole preload game
Could you describe the method/tool(s) you used to measure your preload on each cylinder to such an accurate (thousandths) precision?
I will likely be needing to do the same thing very soon, and I want to make sure I do it right. Also, if a specialized tool was used, about how much did it cost and where'd be the best place to find one?
I'm new to this whole preload game
Could you describe the method/tool(s) you used to measure your preload on each cylinder to such an accurate (thousandths) precision?
I will likely be needing to do the same thing very soon, and I want to make sure I do it right. Also, if a specialized tool was used, about how much did it cost and where'd be the best place to find one?
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I personally don't think that the lifter preload is that critical with the Comp R's as long as it's below something like .025.
What lash caps would you use? When I last used some it was 2000, and we had to take some and modify them (sort of ghetto).
What lash caps would you use? When I last used some it was 2000, and we had to take some and modify them (sort of ghetto).
#17
Here it is word for word out of the Comp catalog
Pro Magnum lifter must be installed on an engine
with ADJUSTABLE rocker arms and preloaded to
.002"-.004". Always set the preload with the engine warmed to
normal operating temperatures to allow for thermal growth
http://www.compcams.com/Technical/Ca...ML/279-282.asp
so..run them at whatever preload you like..but you run the risk..and dont call Comp to warrenty your lifters once they fail
Pro Magnum lifter must be installed on an engine
with ADJUSTABLE rocker arms and preloaded to
.002"-.004". Always set the preload with the engine warmed to
normal operating temperatures to allow for thermal growth
http://www.compcams.com/Technical/Ca...ML/279-282.asp
so..run them at whatever preload you like..but you run the risk..and dont call Comp to warrenty your lifters once they fail
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Originally Posted by spectacle solutions
Here it is word for word out of the Comp catalog
Pro Magnum lifter must be installed on an engine
with ADJUSTABLE rocker arms and preloaded to
.002"-.004". Always set the preload with the engine warmed to
normal operating temperatures to allow for thermal growth
http://www.compcams.com/Technical/Ca...ML/279-282.asp
so..run them at whatever preload you like..but you run the risk..and dont call Comp to warrenty your lifters once they fail
Pro Magnum lifter must be installed on an engine
with ADJUSTABLE rocker arms and preloaded to
.002"-.004". Always set the preload with the engine warmed to
normal operating temperatures to allow for thermal growth
http://www.compcams.com/Technical/Ca...ML/279-282.asp
so..run them at whatever preload you like..but you run the risk..and dont call Comp to warrenty your lifters once they fail
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Originally Posted by spectacle solutions
well..I think I would trust the company that supplies the parts..wouldn't you?