Setting valve lash with cro-mo pushrods

[Richierich56]

Hi all

Had car out this weekend at BugJam for first few runs and having set the lash at 0.06 the noise from the valve train was excessive. I have now read various threads elsewhere that advise to set lash at zero with cro-mo pushrods....what's everyones thoughts on this? Also, if it is the case that they should be set at zero, what movement should there be in the pushrods? Spinning freely or otherwise? Thanks

[Iryanu]

I set them at a "loose zero"

just tight enough that you can spin them between index finger and thumb, wobbling the rocker arm shouldn't have any play.

[Jim Ratto]

I don't like the way my car idles cold with them at 0.00" so I set my Berg pushrods at 0.002"
there is some noise, but once warm no more than when they were at 0.00" but the car runs better cold.

[nicolas]

i set mine at 'loose zero' as well. the process i use is to adjust them just as much so you can turn them with your fingers. that probably is what Richierich and Jim refer to, but without measuring.

[Richierich56]

Ok fellas, thats great advice - thanks a lot. Rich

[dragvw2180]

 Set your valve lash as close to zero as possible with the engine cold , then drive it four or five miles , recheck your valve lash hot. I think you will be surprised at how loose they are. My point is that when doing zero lash a few thousandths one way or the other will not make much difference using CM push rods as long as there is some lash .   Mike McCarthy