What kind of difference would you expect to see if you just swapped the heads for some very similar flowing RPM heads, assuming the CR stayed the same?
I have a some other 408-416 to compare to on file. O ne that comes to mind with Edelbrock ported by another shop with pushrods tubed made 470 ish hp but lower compression and flat tappet cam and Airway. Oh and they were the Magnum Edelbrocks. I will look some past builds up. J.Rob
