Now when you say "increase the car performance" - yes it does. Electrical performance. Whether that translates into speed/torque/power I don't know. It really depends on the age of the car, how good is the ground, etc.
Finally, went to dyno tuned my 7AFTE by using emanage. Found out i was running freaking rich whn offboost. I was being told my injector was too big for my setup as Im using GZE 365cc injector