CJ, which tune on the sct were you using? I've gotten to 142 and still climbing when I backed off in 5th. Used Torrie's agressive tune ( the "wild" tune causes knocking/detonation unless the octane is higher than 93)/with magnaflow, intake tube, velocity stack and green cone filter, not lowered at the time,it is now. At 142 the front end started to float so I backed off. It was in the 30's that day, and had less than a quarter tank, that also probably had something to do with it. I'm also running on lightweight ASA 18's with a slightly larger diameter tire than the stock 17's.