Trick Flow 440 heads, The Real Deal?

Well, I'm impressed with his results on a 48 year old shortblock that was rated at 375 HP stock. No mention was made of the type and size of the camshaft though. Whatever it is, it is evidently still streetable. Bolt on a set of OOTB RPM or 440 Source heads and see if he can even get within 50 HP of that.