Despite what many think/believe the 330i is a vey tuneable engine, with just software you can get 20+ bhp and similar torque gains, changes the engine note and sharpens the throttle. Also gains to be had with MPG.
However, the only person that seems to be able to get these gains is Jason @ BWchiptune. He sends lots of 325's and 330's to us for map installs and dyno testing and we are always amazed with what he can do.