i have no idea. but let me offer this, i have a turbo z31. these tend to be ball-less until boost hits. i put in a set of stage 1 (.420 lift, don`t remember duration) and all i can say is "wow, what a difference" cams almost always make a noticable difference, and would be one of the first upgrades i would make to a motor. (that being said, they are only $170 for my z31, so what the fuck .)