I have a custom exhaust, injen air intake, just tuned up 30k mi. ago. Tires are 225/55/16. I keep it tuned with all services all the time. I have had the car for 7 years. My reaction time differed, I made 3 passes. It was from .7 to 1.5 sec. for reaction. 17-18 et times. I race cars pretty often and consider my self to be a very good driver. I hold the brake and rev the to max before the brakes let go and launch. It does not burn tires it feels like a perfect start. I also drove my brothers camaro SS and ran 13.3 with the factory stating 13.6 et .