# Valve lash ajustment?



## bobby326 (Dec 13, 2009)

I have read numerous threads about valve lash ajustment and would like to get correct advice. When you get to zero lash with the rocker ive read that you should go 1/4 - one full turn past zero lash. What is correct. Some say 1/4, 1/2, 3/4 and full turn. Just want to know what the correct lash is. My engine is a 67-326, xe262 comp cam/ lifters, some head work, comp magnum rockers, eddy rpm intake, 600 holley, hei dist. Any advice would b appriciated. Thanks


----------



## RunninLeMans (Apr 3, 2014)

You could ask Comp Cams what they recommend in thousands of an inch, but anywhere in the 0.025" range is a pretty good start. How do you get there? A 7/16-20 threaded stud has 20 threads per inch, or 0.050" per thread, so 1/2 a turn gets you 25 thou. If your stud is different, gotta do your own math.


----------



## 646904GTO (Feb 10, 2008)

Pontiacs like a tight lash so go 3/4 from zero and if you get some ticking at idle you can go more. One way to find the limit and the old school way was with engine running turn down to misfire and back off 1/2 turn. This buries the plunger but under some conditions can cause shut down on hard decel. As you can tell there are lots of ways. If you really want an accurate measure on your particular engine with a cold engine and an unpumped lifter turn it down to zero lash and then go until it starts to open the valve, back it off 1/2 turn and try it. Myself I do the first method, 3/4 down and if it rattles go another 1/4


----------

