Quite a few of the posts to this thread do not address the original posted issue. What is available for aftermarket exhaust systems for the X3? Any real power gains are in the headers and catalytic converters, mufflers are good for 5 or so rear wheel horsepower at best. Haven't seen any mufflers even that are listed for the present model. This is 2009 and the current powertrain has been out since the 2007 model year. We also need intake systems and reprogramming. Where is it?
2008 BMW X3
2006 Porsche 997 2S Cabrio