Well I just bought Nitto 555R's and only got 3 runs with them because the place was slammed! I was only launching @ 3200 rpms, I think it still would have hooked even @ 4000. Only thing is this car is my DD with a stock clutch, so snapping halfshafts and things are not options. I know it CAN run 12.4-12.5 with a nice 1.7 60'!!!