Are you talking about Performer RPM heads or Victor heads? Hughes Engines Shows their Big Mouth RPM's flowing 322@700. I had mine CNC ported by Modern Cylinder Head. Don't have my flow sheet in front of me but I think they were not that much somewhere in the 310-3320 range. I don't know anything about the Victor's if that's what you are looking at. I know my buddy runs the same cubic inches with the W5's and has run 9.70@136