Torque converter
I'm running similar 360 power level with 904 and 8"ATI converter. 29.5 bias slicks, 4.56 gears in my Demon. 60' is usually 1.55 if track is prepped. I did gain both 60' and 1/8 mile performance changing to this converter. The converter stalls dead on 4600. I leave on the 2step at 2700 and shift at 5800 going through the lights at 6200.