LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Roller Rocker Question

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Old 04-29-2008, 01:19 PM
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Default Roller Rocker Question

those of you guys that are running cam and RR's.. .what kind of clearance(if any) did you run on the valves.
Old 04-29-2008, 09:35 PM
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Default heads

Originally Posted by 93z28_6spd
those of you guys that are running cam and RR's.. .what kind of clearance(if any) did you run on the valves.
hi there just wondering what the flow potential of the lt1 1995 cylinder heads were and can you get away with 11.1 com because of the reverse cooling in the heads thanks
Old 04-30-2008, 11:35 AM
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dont know man, i just wanted to know what clearance to run on the roller rockers.. sorry i couldnt help
anyone else
Old 04-30-2008, 12:47 PM
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Are you talking a hydraulic roller cam or solid lifter, roller cam?

I've got GMPP roller rockers with the Comp Cams hydraulic roller lifters in my LT-1, and I've set the lash at 1/4 turn down from "zero lash". CC says to set them at 1/8, and I normally woldn't argue with a manufacturer on how to use their products, however at 1/8 turn, I was getting a noticible "ticking".
Old 04-30-2008, 01:06 PM
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i have stock lifters and 1.6 Roller ROckers...
so about 1/8 to a 1/4 turn?
i appreciate your help man
Old 04-30-2008, 01:09 PM
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'93

assume you are talking about "hydraulic roller" cam....1/4 turn past zero lash

iff solid cam, spec for lash should be on the cam card

Leadfoot:

if you have the COMP 875R lifters....the lash REALLY needs to be zero to 1/8th turn MAX. Excessive cam lobe wear or failure will resuly if you lash the 875's to tight. The 875's will have more "noise" than the 850's

If you have the 850's than 1/4-1/2 is fine
Old 04-30-2008, 01:20 PM
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alright thanks for the help.. i really appreciate that
Old 04-30-2008, 04:51 PM
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Originally Posted by ******

Leadfoot:

if you have the COMP 875R lifters....the lash REALLY needs to be zero to 1/8th turn MAX. Excessive cam lobe wear or failure will resuly if you lash the 875's to tight. The 875's will have more "noise" than the 850's

If you have the 850's than 1/4-1/2 is fine

I do have the 875s, but at 1/8 turn they were quite noisy. It just didn't seem right.
Old 05-01-2008, 06:15 PM
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OK, I had a little spare time today...I backed off the preload by 1/8 turn, so it's now at 1/8 turn. The biggest PITA to this job is removing the shock tower brace so I can get the valve covers off.
Old 05-01-2008, 10:24 PM
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hey thanks for all the help... so it sounds like i will be doing a little bit or RR adjustment here when i get some time
thanks again
Old 05-02-2008, 12:09 PM
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Default 875's

Originally Posted by leadfoot4
I do have the 875s, but at 1/8 turn they were quite noisy. It just didn't seem right.
they will make more noise.....but that is the trade off for running the 875's.

I have seen a cam lobe wiped because of to much preload on the 875's

My $02 is you did the right thing by backing the lash off.
Old 05-02-2008, 02:54 PM
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Originally Posted by ******
they will make more noise.....but that is the trade off for running the 875's.

I have seen a cam lobe wiped because of to much preload on the 875's

My $02 is you did the right thing by backing the lash off.

Hard to believe that they have so little plunger travel that 1/8 turn will make that big a difference....I mean if you cranked it down 1 full turn, and then went 1/8 MORE, I realize that would be a big concern. But, to go 1/4 turn from zero lash instead of 1/8 turn, and risk taking out a cam....WOW!!
Old 05-02-2008, 03:58 PM
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lead..

the 875's are almost solid lifters, they do not want more than 1/8 turn. Very little travel in their plungers. good lifters, just need to be lashed correctly. they can rev higher than the 850's

I have the cam but no pic in my files.....1/2 turn fing wiped the lobe in less than 2000 miles.
Old 05-02-2008, 11:02 PM
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I run the Comp 875R lifters. They need very little preload after zero lash. I mean very little.




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