I ran an old 11" 2200 r.p.m. stall Fairbanks behind the old 383with E-heads,8.0:1 compression, small cam@ 15 lbs. of boost without any ill effects. It was originally bought in the mid 80's by a friend, and I got it in a bunch of parts which was part of a barter/trade deal. I ran it because I had it, but it wasn't right for the combo. Didn't hurt it and couldn't" drive through it" like I did the cheap 10" 3K stall I tried later. I still have it, and would use it again with confidence in the right application. I currently have a 9.5" Dynamic behind the 470 which was built for the combo. It acts like a "loose" convertor for the first 15 feet from a dead stop, drives like a stocker after that cruising unless I get on the go pedal, when it becomes a loose convertor again. Really the best of both worlds. If you have the $$$ have one made by a good company to your specifications. If no bucks are available for the "right " one get the best name brand, non-custom convertor you can afford.