Quote:

?????????????You are going to have to....explain.......??????????????

VALVE LASH or VALVE CLEARANCE is measured between the top of the valve stem and rocker, not the push rod.

If you run hydraulic lifters, they are always under "some" preload

If you run mechanical lifters, the "push rod" clearance is never actually measured. It would be somewhere in the vicinity of the valve clearance multiplied by the rocker ratio, I guess

In other words if the valve clearance is .025 (say) and you have 1.5 rocker ratio, the (in theory) clearance at the pushrod would be .025 / 1.5 or about .016




I think what he's asking about is clearance between the pushrod cup & the rocker when the valve is fully opened if the pushrod is to long & the ball adjuster is backed out to set valve clearance the pushrod cup can rub the rocker arm as things change due to thermal expansion & as an effect of high RPM valve train oscillation/flexing/what ever you want to call it... I think a minimum of .060 would be safe & .100 is likely better...

Typically the rule of thumb when measuring for pushrods is three threads showing on the adjuster screw then set your adjustable mock-up pushrod to length with valve clearance built in & use that measurement to order your pushrods...

"The Armies of our ancestors were lucky, in that they were not trailed by a second army of pencil pushers."