Pushrod Length Checker
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From: Johnsonville, SC; but orginally from GAINESVILLE, FL
Originally Posted by vettenuts
I think I answered this on CF, did you post it there as well?
You install the checker just like a pushrod and install the rocker, with the valve on the cam in the fully closed position.
You have to adjust the checker till you have NO PLAY.
That is 0 lash.
You may have to remove the rocker a couple of times to get it right unless you can screw the adjuster with the rocker installed.
Then carefully remove the checker, measure with a good caliper and add the length of the preload you want.
.025" is considered correct.
In other words, the length of the checker at 0 lash + .025".
Some lifters are more tolerant of more preload, but not much more.
RHOADS lifters are almost .060" of preload.
You have to adjust the checker till you have NO PLAY.
That is 0 lash.
You may have to remove the rocker a couple of times to get it right unless you can screw the adjuster with the rocker installed.
Then carefully remove the checker, measure with a good caliper and add the length of the preload you want.
.025" is considered correct.
In other words, the length of the checker at 0 lash + .025".
Some lifters are more tolerant of more preload, but not much more.
RHOADS lifters are almost .060" of preload.
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"Most here would shoot for .050 to .075... Tony (AFR) has a write up on it..."
All depends on the lifter too:
Comp 850-16 OE replacement - .050-.075
Stock - .080-.120
Morel - .030
Comp R - .008-.010
Double check these numbers. don't use my list as the word ( except Morel, I'm 100% positive on that one )
All depends on the lifter too:
Comp 850-16 OE replacement - .050-.075
Stock - .080-.120
Morel - .030
Comp R - .008-.010
Double check these numbers. don't use my list as the word ( except Morel, I'm 100% positive on that one )
Is the search feature broke again? 
According to Tony from this thread - https://ls1tech.com/forums/generation-iii-internal-engine/455714-comp-xe-r-lobe-base-circle-vs-stock.html :
According to Tony from this thread - https://ls1tech.com/forums/generation-iii-internal-engine/455714-comp-xe-r-lobe-base-circle-vs-stock.html :
Assuming heads are in place with the proper headgasket (or the same thickness shims during mock-up), the following is a quick rundown to check and measure for proper pushrod length:
Install an adjustable PR initially set too small (makes sure cam is on the basecircle of the lobe you are checking)
Bolt down the factory rockers....
Set the adjustable pushrod to zero lash and remove
Measure pushrod, then add .050-.100 to that figure which now represents your pushrod preload into the lifter and the total length of the pushrod your engine requires. This is obviously quickie instructions for a factory rocker arm set-up (pedastal mount).
Install an adjustable PR initially set too small (makes sure cam is on the basecircle of the lobe you are checking)
Bolt down the factory rockers....
Set the adjustable pushrod to zero lash and remove
Measure pushrod, then add .050-.100 to that figure which now represents your pushrod preload into the lifter and the total length of the pushrod your engine requires. This is obviously quickie instructions for a factory rocker arm set-up (pedastal mount).
