904 or 727 ?

Currently running 904 in my 71 Dart 408. Probably in the 530 to 550 hp range with 3500 converter. Only running on the street at this time. Very, very happy with it! John Cope built the trans with manual reverse, nothing super exotic, just good parts. See my pictures and specs for more info. When I start racing it, I will probably pull it out and go with a low gear set, a brake and beef it up a little.