I think the brodix head is a lot better head then that dart 308 for sure. If the price is right I would try for them, the motor will thank ya later. I agree 775-800hp isnt out of sight for that motor at all.
I went racing friday night, car slowed up some and smoked when I got out of it at the finish line. I felt I might have a blown intake gasket so came home and pulled it apart and my guess was right.