The "Guys with automatics" have done before and after testing with G-Tech pros and G-Tech Pro Comp instuments and they showed deffinate... Not "Butt Dyno" .... improvement in real numbers. Do a search. I have my numbers at home. If I remember I'll post them again later. I've posted them many times. As I've said before.... As soon as I get some spare time I'm going to take mine and get it Dynoed mainly to see how the real Dyno numbers compare with the G-Tech numbers.