With the auto it's tough to get any extra power you can feel. An engine chip will be the biggest bang for the buck, but shouldn't do so much as to damage the tranny. I have heard mixed reviews on transmission chips. If you do the other 2 mods also you will gain a few HP, but they give more of an improvement in sound (and if going to aftermarket exhaust, weight). With all 3 mods it shouldn't take a lot of miles off the tranny (it will shorten it's life, but not by more than 2-5%) Hey I have a 95' 325i automatic.....what modifications should I make in terms of performance.. Intake? Exhaust? Chip? all of these? and would the mods. make a drastic increase in horsepower, torque, etc.? I would appreciate the advice. Thanks!!