An alternative means of measuring valve-to-piston is to rig the valves with light checking springs, and then installing the head and valvetrain with a dial indicator reading off the retainer. Start at 20 degrees BTDC, set the indicator to zero, and then work the exhaust rocker by hand until the valve hits the piston, and read the indicator travel. Repeatedly adjust the crank position 2 degrees forward, re-zero the indicator, and check again. The reading will diminish to the minimum V-to-P value, and then open up again. Next, perform the same procedure on the intake valve, moving from TDC to about 20 degrees after.