that's fine

502 rw heads/cam stock bottom end... call it 550-560 conservatively at the flywheel
http://www.youtube.com/watch?v=OI73M1yPdFU

his cam is about the same size as mine but it is matched with good heads as well.

some guys are going 450 rw cam only... depending on the cam and dyno.

that is not to say that everybody does, but its not unbelievable