I don't think the posted results are impossible, based on what I found when I flowed the head and looked at the intake port design. I think if the engine makes that kind of power, give or take 50 hp, it must be a pretty good piece. I just finished a Hilborn injected 429 cube FE with my Street Pro Ports that made 716 hp with a .525 lift cam, so this 482 is not unheard-of power........and before anyone cries foul about Morgan's dyno, I tested the engine on Tony Bischoff's Superflow 902.
I have a pair of those heads going on a 390 that I plan to sell, using my .525 baby roller. I am not sure yet if I am going to fix a few things about the ports, or run them as-is. I'll post it in the dyno section when it happens.
I don't know andyf, or the person who did the 482, and I am not about to say it is not a real number. With that said, as I have said before.....we race on racetracks, not dynos. This is apparently a street 482, and I'd safely say that it will make the owner happy. I say if all involved, and most importantly the guy who laid down his coins are happy, then all is well!