I have a transmission specialties C4 spragless torque converter made for 70 and up. It is the 10" 11 7/16 pattern. stall is set for 2500-2900 and will handle up to 700hp. The converter also has the ballooning plates to handle nitrious. The part# is 10102XHDXLS. I just called today and verified all specs on it. This item is brand new, it has been test fitted on the tranny and then pulled off. They currently have it listed for $450 plus shipping i am willing to part with it for $250 plus the ride.