Hi guys, im looking to find out how much the valves on a Zetec Blacktop protrude into the bore on full lift, so dimension from head face to valve face.

Project is to try an ST-170 Head on to my crate Blacktop bottom end using standard pistons with Piper 285' regrinds .

Thanks in advance for your help, Paul

I suspect the only safe way is to measure it carefully ,Do a dummy build and use plastigauge between the valves and Pistons . I have used thick solder through the plug hole in the past on X flow and A series engines which can save having to strip and rebuild the head from the engine.