[ponyakr]

"...The stock factory hard parts in a T 400, 4L80E, will live just fine to 750 HP..."


Not for the sake of argument, but just to present my differing opinion, I don't think the factory int sprag or roller clutch that came in most Pontiac TH400's will live with that much power. I broke 2 of the stock 16 element sprags, with only about 400hp/500 torque.

My trans guy, at the time, installed what he called a 500 Cadillac sprag, in all my bracket TH400's, and I never broke one. I assume those sprags were about equal to the 34 element sprags used today, for HP TH400 builds.