70mm or 75mm TB, which one for a stock engine?

[mlambrecht82]

I put a 75mm throttle body on my practically stock '02 GT and man I lost a lot of power. I now have a blower and am looking to go with a 70mm. I would loose power with a 75mm, even with a blower. I wouldn't change the throttle body if I was you. It will slow the vilocity of the air down. Unless you have forced induction or nitrous I wouldn't mess with it. The bigger throttle bodies only are bigger on the inside, the out side is virtually the same diameter. It's hard to get power without investing a lot into your car, at least with my experiance. You should probably save up for a nitrous kit. Zex makes a kit for your car that was tested by MM&FF and turned out good results. It's adjustable up to 150HP. If you run the kit at a 75 shot you should be fine and feel a big difference in performance. I think pricing is around $500-$700. Other weis you might want to talk to a performance shop who has experiance with your kind of car.