"The worlds's best cam combined with a poor set of heads will produce an engine that's a dog. But bolt on a set of great heads even with a poor cam and that engine will still make great power."

I will add that a good free flowing exhaust system and good free flowing intake system to the list so as not to restrict the heads. Allen

 

And the point?

 

By a set of great heads and a ****ty cam? :shrug:

Oh. And a good exhaust system.