you may be correct..im just goin on info that i have acumulated from a shop around here..i was asking about stage 3 cams and they told me i would have to do the entire vlave train..he told me i could run stage 2s with stock valve train but since the price for the stage 2s to the stage 3s dont differ too much then it would be worth it to upgrade all..sorry if i relayed false info.