[Mike Taylor 3601]

Jeff,
I believe what you are talking about on valve pockets is on TRW pistons most of them the valve pockets are'nt machined they are made when piston is forged,so pockets vary in depth and location.They vary because they are there before rest of piston is machined.
Anyone that has ever flycut a piston w/pockets forged will tell you they are inconsistent for depth and location.
I'm sure JE or any other piston maker would'nt rely on a piston with forged valve pockets to locate there valve pockets,all that info is going to come from there programs that will have valve pocket locations,spacing etc.
Mike Taylor 3601