the full potential of any cylinder head is dependant on the camshaft that is controlling the opening and closing of the valves. A poor set of flowing heads on a well built "MATCHED" combination will make more power then a set of great heads on a mis-matched combination. Not one part is the magic gizmo that makes power. . .its a combination that makes power.
A filet is good, but add an Idaho spud with real butter, grilled portabella's, some steamed veggies with Cajun seasoning and a tall draft in a frosted mug. . .now you got a hella of a meal!!! Same with engines. . .to hell with it I am going to the lake to get a beer!!
Chris