Good information here guys. I know your combo does mean alot when you running stick or auto. I will tell you one thing though the year before last when I was waiting to buy a Jerico I ran a reverse valve body T400 with a trans brake in my 67 Camaro with a 5500 rpm stall and 456 gears. I left around 4600 rpm on the brake. Best ET was 11.07 123mph
60ft 1.51 best.
Last year I put the Jerico 4speed in with a 19lb. aluminum flywheel and 488 gears. Best ET 10.40 128mph 60 ft best 1.38. I had the exact same motor and tuned it the same way. With my set up on the motor it liked the Jerico better than the T400. This is the only comparison I have cause I always run sticks. Don't get me wrong now the automatics leave awesome with a brake.
Now pro stock and alot of other guys run clutchless trans which I thing is even quicker and you could pick up a couple hundreds on ET.
I always heard the converters slow you down alittle.