Piston deck height, heads CC, head gasket thickness, cam lobe seperation angle, installed cam intake lobe center and valve opening at 10 degree BTDC to 12 to 15 degrees ATDC will determine how much piston to valve clearances you will have I have read on here that there are two different grinds, versions of the Mopar "590" solid lifter cam The lobe seperation angle being the major differences, hopefully someone that know more about that cam will chime one way or the otyer on that