I disconnected the negative cable today for like 5 minutes and then let the car idle for another 5. I havent really raced after i got my full exhaust installed, but felt the difference in a third gear pull. Yet, id really have to race and will see the difference i guess. How much do u think i have gained to the wheels with the ams turbo back? For some reason i dont even feel when im going fast in my evo lol i dont know why i guess im used to the speed.