Active Autowerke GESI Ultra High Flow Cats X Pipe - E9X M3 08-13Active Autowerke is proud to release the highly anticipated GESI G Sport cats upgrade Connecting Pipes to the Signature Track Pipe with X Pipe for the BMW E9X M3. This is intended for those discriminating car owners who already have an Active Autowerke Signature Track Pipe and would like to remove the CEL without using a tune while meeting emission requirements as specified by the EPA. This exhaust system was designed and engineered to work with most