End of year HP

[Alan Roehrich]

Originally Posted by M Brand 505B

Keep in mind these heads still have to CC and have the same valve size as the head you're replacing.

Are you really sure about that?

The GMPP 401 head is actually an Edelbrock head (and in fact, the Edelbrock head itself is now approved), I'd strongly suggest that you look at the difference in specs for it and the rectangle port closed chamber heads it replaces. It (the replacement head) has its own chamber cc, port cc, and exhaust valve size.