The stock exhaust system on the BMW leaves a lot of room for improvement. It does a good job at suppressing exhaust noise, but also corks what is otherwise a wonderful sound. cp-e™ has designed a two part system, the QuickPower™ pipe and the Austenite™ Cat Back system, to get the most out of your Austenite™ Cat Back system features our new muffler which is internally similar to the one used on our cat back, but it was specifically designed for the 135's single inlet/dual outlet design. This new muffler has been lengthened and a small baffle was added to increase noise suppression. We have also added our cp-e™ Stealth™ pipe to keep the Austenite™ Cat Back system from droning.

The resulting sound is nothing short of intoxicating, and we would be surprised if your stereo gets much use after installation. The low-rpm range now has a warm and mellow tone without sounding too boomy. As you move further into the powerband the character changes from a baritone grunt into a frenetic roar. Our exhaust is a dramatic improvement over the flat uninspiring tone produced by the stock setup. It gives the 135i a more aggressive character without becoming overwhelming. Most importantly, there is no drone! We believe that it provides the perfect blend of performance, sound, and appearance, without any of the drawbacks from which most aftermarket exhausts typically suffer.

The catback replaces the rear section, which includes the rear muffler and tailpipes. Or opt to replace everything from the downpipe back, which includes the larger diameter QuickPower™ midpipes and optional 8-inch hybrid mufflers. No matter which options you choose, the cp-e™ exhaust is a 100% bolt-in system that requires no cutting, grinding, or welding. Welcome to the product of serious engineering.

The Cat Back System will come complete with step by step instructions and all necessary hardware required for a complete and professional installation.

IMPORTANT: This system is not compatible with convertible models.