[TahoeM3]

Good times. I ran a 12.8@108 stock in my X5M timed by VBox, but that was on an unprepared track in 90+ degree heat.

I think the 50i will run best times with brake torquing to around 3000 rpm in manual mode and letting the transmission shift itself, but short-shifting it is worth a shot to keep the torque in the peak.

Airbox mods are definitely going to be helpful. I'd bet that just removing the carbon filters would be worth 15 or more hp. A switch to an M-style airbox would make a big difference.