Im still trieng to decide the same thing bro. Allot of these guys say z06 cam is cool, others say not cool, either way you go on cam you gotta upgrade the springs and pushrods. Im just gonna wait and Get a cam, springs, retainers, lifters, pushrods, valves, ect.. along with P/P heads maybe cryotreated and thermal coated all in one shot. May be more exspensive but It will be worth it.