I usually do not refer people back to a dealership service department especially if their vehicle is no longer under warranty. However, I would speak with an advisor at BMW (or a shop certified in European car repair) to get the specifications of how you will need to properly re-modify your vehicle. They will need to look at it to see what the best fix will be.
〉 Answered on Jul 13th, 2012 by Diana Claussen, Owner / Writer at Auto Goddess
Emission tests differ from state to state, with California being probably the strictest. If you can pass in CA you can probably pass anywhere. However, it will be difficult with all those modifications unless you go back to original status of vehicle.
〉 Answered on Jul 13th, 2012 by Jo An Holt, Automotive Journalist at Holt & Associates