I have a Sprint Booster, but I did not drive the car with it installed before installing the Renntech kit, so I really don't know what it would have done when the car was stock. The best to my understanding of the Sprint Booster, the Crossfire's have a sort of memory that it keeps track of how you have been driving and communicates to the throttle response. I believe it kind of keeps the computers memory erased so that the car reacts more like a car that has a direct mechanical connection from the gas pedal to the throttle body rather than using the throttle positioning sensor. I asked the guy's at Renntech if the Sprint Booster would effect their kit and they said they didn't believe in them, I have thought about pulling mine out and selling it if I could see no difference in how the car reacted.