I ran a best of 12.7 @ 105 mph and 1.6 60ft last weekend in mid 60 degree weather. I can run a consistant 12.9 @ 104mph with 1.6 60ft. Part of the reason though is that I launch hard off the line. Rev limiter hard 6250rpm. But we have 31 spline axles from factory so they are stronger and will hold up more than a 28 spline. In case you are wondering my mods are as follows... Ford Racing shorty headers, Bassani X-pipe with cats, Magnaflo Bullits, AFE CAI, Jet throttle body spacer, Moto Blue underdrive pulleys, Hurst short throw shifter, msd digital shift light, BMR rear lower control arms, BMR adjustable upper control arm (pinion angle set at -2) (eliminated wheel hop100%) Ford Racing 3:73's, and X-calibrator 2 with 3 JDM Engineering custom tunes, Race 93 octane, Street 93 octane, street 87 octane, yet i can return my car to stock mode any time i feel like it. These mods have not required a custom tune but new it would give me more power. I dyno at 287rwhp with out tune and 297 with the tune. I was not to impressed with the dyno numbers but my car kicks but at the track. I forgot to mention et street 26x11.5x17 too, work well on stock rims.