Before I'd done my research I'd always heard that the 904s couldn't stand up to much power. I'd already picked up a used race prepped 727 with converter from Texas before I found out that today most racers prefer the 904. Because I was going to have to make a new driveshaft when I swap rear ends it seemed like the opportune time to go to the 727. I wish the 904s and 727s were direct swaps so I could interchange them easily.
Correct me if I'm wrong, but I'd also heard that it was expensive to build strength into the 904s.
