Piston to valve clearance

SSStang said:

trickflow 1.6
Just to double check after zero lash turn 1/4 to 1/2 to set preload? That is what i'm doing when checking the PTV and I made my own solid lifter by taking a lifter apart.

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You check with a solid lifter at zero preload. If you preload a solid lifter, you're actually lifting the valve off the seat and reducing "true" clearance. Preload is for final assembly with hydraulic lifters, not for checking PtV with a solid lifter.

Just stick the rocker on the stud, make sure everything is aligned, and spin the poly lock down by hand. With the other hand, hold the pushrod and kind of jiggle it up and down to feel for play. When you don't feel any play in the pushrod, you're at zero lash; stop tightening the poly lock. (At this point, the poly lock should feel tight, anyway.)

Spin the engine over twice, tear everything apart, and check the minimum thickness of your clay.

THAT ALL SAID, if you're hitting the piston with 1/2 turn preload, you're probably still not going to have enough clearance (if any) at 0 preload.

Did you measure the actual clearance? Even if it clears now if there is not enough margin you could still have valve to piston contact when the engine is running and parts are expanding, etc. I'm not questioning your ability, just trying to make sure you don't end with an expensive problem.