valve to piston checking tool

[Ed Wright]

I made a little fixture that hooks on my Jessel rockets at the push rod end, uses a 1/2" break over, using the actual heads & used head gaskets, "checking springs" installed, pull the valve down against the piston, measuring actual travel. Ex from 10 deg BTDC, until TDC. Intakes from TDC. to 10 deg ATDC. Two degree increments. I have checked mine with checking springs vs racing springs. On mine, subtract about .004" from the checking spring VTP clearance. I have learned how much I need with checking springs, so only check it that way now.
This works for me. If a pro has a different recommendation, I defer to them. This is just how I have done it for several years.