In dynoing, Scott is right. First test done was exactly what your are asking. Do the lumps help in a otherwise stock head. The short answer was no.
Starting with larger valves and porting was done next. Major HP and tq was found, even with the stock cam.
Lastly, changing the cam compounded the power gains a equal amount as the performance head.
P.S. Heard from a customer tonight. He ran a PES intake on a Dyno and witnessed a 7% gain over a Clifford. Take it or leave it. This was a circle track setup with a 2BBL.
