Here's a tidbit of info for you guys:
Roush engine shop tested a 427 with a set of AFR 225's. Then, due to some unforseeable circumstances, needed to swap in another set of heads...DART, which is nearby Roush's shop, got them into a set of CNC 225's. Power was up 26 hp and torque was up 13 ft. lbs (everything else the same). And this was with a head that flowed less by the numbers at each lift.
