so ive been reading and searching allot, but i cant figure it out. if you have a stock 5.0 minus say exhaust and cold air, what heads get you what horsepower? thumpers i have heard get you 30-40 more than stock,. when its just the head. yet i see other aluminum heads advertising 70 hp over stock... whats the run down? how about with other stuff like a simple cam? how can you get 350 hp out of a h/c/i on the stock block. i know you'll probably need 30 or 24 pound injectors for that, but whats the simplest way to do that?