quik all this makes sense and I am not trying to argue, but who has some real evidence that swapping the truck intake would be better??? when I dynoed mine it pulled straight up to 6200rpm and then it just kind of flat lined all the way to rev limiter ~7200rpm? I know rwhp on a piece of paper looks good but e/t wise, who has proved that the truck intake is actually a POS for the trucks? I just keep on searching and really kind find proof of it... everyone that has ran better records "e/t" has the truck intake, and people that I know that has gone with the LS6 intake has gone back to the truck intake due to unsatisifed performance...

or does anyone know???

by the way to stay on subject, why not not mill the heads?

 

Wouldn't milling the heads only increase compression by reducing the combustion chamber size? Couldn't you produce the same effect by using a smaller cc combustion chamber heads without milling?