i heard a rumor..... [Archive] - Bimmerfest - BMW Forums

: i heard a rumor.....

04-12-2007, 12:25 PM
but is forced induction with an automatic / steptronic transmission a cardinal sin? I've heard it can be hard on your tranny... but I'm looking at a non-intercooled 6psi VF set up and I have a 5 speed auto.step. Would this blow my tranny or will I have to upgrade something? Perhaps the rear diff???

I have heard that BMW rear diffs on 3 series are built like a tank... I wanted some input on this subject.

04-14-2007, 10:56 PM
there are a lot of successful fi bimmers with steptronic. i chose to upgrade my torque converter and throttle body tune, but you don't have to.

04-25-2007, 01:48 PM
The only problem between the 2 transmissions is the auto eats some power when compared to a manual