HEADS.
and an intake. Big cams don't do much good if the intake/exhaust sytem can't utilize what the cam brings to the party. That intake and stock heads can only flow so much air/fuel, no matter how far the valve opens, or how long it stays open. That's where you run into "killing" the engine with too big of a cam. Ya loose port velocity. Think of it this way. You have a 1/2" garden hose that you wash your car with. Inside the house, there's a 1/2 copper line that feeds the 1/2 spigot. With me so far? What would happen if all we did was switch the spigot with a 3/4" one? Might get a little better flow (read as power) but prolly not. What happens when we put a 2" valve in there instead? The water gets lost in the big valve now, and not much comes out the hose, we lost our velocity.
A VERY crude metaphor, but you get the idea. Simply adding a cam nets you very little horsepower. When selecting a cam, planning for the future is a good idea. In fact once you add the other goodies, that new cam will keep adding to the mix.
Make sense? I hope so. Just tryin to help ya out!
