You will want to get an MSD window switch wired with your system...here's why. Nitrous is activated at wide open throttle. Since you have an auto tranny, you will be at WOT throughout your race, you don't let off the gas to shift. Since you are still on the gas, the nitrous will be spraying during the shift...this is bad. The window switch will turn on and shut off the nitrous at desired rpm levels, so you will want to shut it off a few hundred rpm before the auto shifts.