I would have responded earlier but something was up with the site . . . I dont have any data per-say . . . I go off what I have heard. Just about with 90% of other thing on this website. The data that I get is from people butt dyno's. There has been several member say/tell me that after replacing there aftermarket IC with Godspeed units that they felt a difference in the car. Can't remember the name of the person that somewhat convinced me but he has a White z with White wheels, I meet him at the last Empire Z car meet. I know he come on this Forum, He also has/had a Supra as well. Maybe he will chime in.