This is the AOD converter I am selling: http://www.jegs.com/i/TCI/890/433100/10002/-1 Stall speed is based on your combination so I cannot tell you what it will stall exactly on your motor, but I can tell you it was PERFECT behind my 302 with Anderson N-41 cam. Worked great with GT-40P heads and the AFR's I replaced them with. Very streetable, and a fantastic strip converter as well. Good for transbrake/nitrous applications as well. About 2000 street miles and 20 passes on this converter (all motor passes). $350.00 plus the ride The C4 converter is almost new. It came with my Performance Automatic Super Comp C4. It is the fully built hard-core PA converter. I only put about 3 passes on it, and 200 or so street miles. It is a streetable converter, but was a bit too loose for my little 302. 11.5" Bolt Circle $400.00 plus the ride.