1987ZTPI

I've got a 87 305 TPI roller motor and i wanna set valve lash people have told me to set it at 1/4 turn past zero lash and others have told me to set it at 3/4 turns isn't that to much pre-load on the lifters .

Mkos1980

iTrader: (8)

No its not. Factory is accually more then 1 full turn. Anything from 1/4 to 1 full turn is fine. But I personally run mine around 1/4.. I've done back to back tests on the dyno from 1/4 to 1 full turn. Power was the same along with top RPM. No differance.

89Nighthawk

The rule of thumb is 1/4 to 3/4 if you adjust cold, not running. If hot and running, back off until it clatters, tighten until the clattering stops and go another 1/2 turn. You want to preload the lifter but not bottom it out.

1987ZTPI

whats the best or easyest way to do it i'm sure it takes longer to do it without the engine running but i don't want to do any damage to my engine by running it without prpoer vlave lash. and i can adjust from 1/4 to 3/4 turn after zero lash and it will operate correctly.

Randy82WS7

it is zero lash plus 1 full turn when warm, or about 3/4 turn when cold

this is to set the plungers to the center of their travel inside the lifters

this is for hydraulic lifters only of course

any true gm service manual shows this adjustment info

it has always been zero plus one full turn

go here and scroll down a little
http://www.centuryperformance.com/valveadjustment.asp

doc

In a high performance book by a well known author, he states (if I remember correctly) 1/4 turn past zero lash. I have set my lash this way for the last 10 years. This is for hydraulic roller lifters with engines having good horsepower and revving higher than stock.