[B Hoth]

I have seen some of this stuff show some positive gains, problem is their allmost allways on auto's with primative computers(easy to manipulate) were they take the results on the initial run. What they don't tell you is that the ECM then corrects for the change to bring it back in line with its design parameters, usually after the car is started the very next time. My sister has a Z4, she installed the turbonator and say's she felt a liitle more power by the seat of her pants gauge and increased her gas milage on that tank by 2 mpg's. She's thrilled, until the next tank and beyond goes back to the original mpg. I've driven it and I can get the rear wheels to turn loose easier with it installed then without. Other then that I feel no percieved difference. The only way things like this can work is if the computer can be reprogrammed for the mod or the computer can adjust more performance from the mod. If you live were you need to get emissions checked regularly then that becomes an issue as well. The engines are now so sophisticated that the only real time mods are going to be pricy and the gains for the most part will be small.