I have 2 similiar engines that I am doing like you describe. One is a 598 inch big chief engine, one is a 632. Did one over the winter also, that one was a 598. Because of the money thing, budget, which is an oxymoron with a big chief style engine, but I am using the Dart Pro-1 18 degree castings, that I tune up. Additional porting and re-vised valve job. For the money, its a hard head to beat. Comes partialy cnc ported, chamber is done, and the bowls. They make 1100hp easy. when I say easy, I am not talking 1 inch lift, and 16:1 compression. I am talking 1 carb, 14:1 ish compression, and mid .800 net lift cam.
Nothing against curtis, but I would have to see it to believe it, that those heads would make 1200 hp. They look nice, and I am sure they will make a heck of a lot of power, but 1200hp isn;t exactly easy, even with a spread port head. Possibly with 2 carbs, and a 1 inch+ lift cam, and maxed compression, and LOTS of rpm, like 8800+, possibly. But those heads won;t do it as easily as a spread port head. If everyone else is using a spread port head, you will likely need a spread port head to compete. Could you run with some of the guys, and even beat some with conventional heads, absolutely. But, unless you don;t care if your middle of the pack, some guys don;t have to be top dog, then you will need the spread ports.
Frank
Advanced Performance
www.get-ap.com