that moved center head should make way more than 630 horsepower, if that is what it is making now. i know ported they go around 350 cfm, as much or more than a big indy head. numbers are just numbers of course. That said, dont know much about that head, as not many are out there, but " in theory" it should make 700 horsepower easily. think they had like a 2.15 intake valve if i remember correctly. i know the much smaller b1ba head will make the kind of power this motor you are talking about currently, does.