I agree the cam is a bit small, hoping the heads make up for it. My hp guesses are based on a 428 ford I dynoed with this same cam but worse heads and intake. It made 430 hp. I figure the inches should make up for a bit and the better (IMO) bore to stroke ratio. Someday I may change the cam, most certainly will change the heads, but beggars can't be choosers and I was given the cam and I already had the heads with the valves.