My best of 13.1 @ 101 is on a stock trans n converter with 20's. 1.78 60' and 8.3 1/8th. Let the truck sit for about an hour and ran 8.2 in the 1/8th and forgot to shift outta 4th so it fell on its face for a second but still managed a 13.1. really think it could have been a 13.0