Active Autowerke Equal Length Mid-Pipe with F-brace – F87 M2 Competition Active Autowerke

For over four decades, Active Autowerke has established itself as the foremost authority in crafting top-notch BMW performance products. With an unwavering commitment to enhancing your driving experience through unparalleled quality, we have become synonymous with BMW’s innovation. Our latest research and development program is a testament to our dedication to refining BMW performance parts and making them accessible to the wider BMW community. In particular, we focused on improving the S55 exhaust sound, which led to the creation of our Active Autowerke F87 M2C and M2CS Equal Length Mid-Pipe (US Patent 11248511, approved in the UK and EU). This mid-pipe offers an alternative to our world-renowned F8X single mid-pipe.

The inline-six engine naturally produces an evenly spaced exhaust pulse, resulting in a rich and harmonious sound. However, the twin-turbo setup of the S55 engine, while providing additional power, has given rise to a sound that resembles two independent inline-three engines competing for attention rather than the throaty roar one would expect. The significant variance in length between the front and rear downpipes, nearly a foot and a half, create unevenly spaced pulses. Consequently, when these pulses merge in various crossover systems, such as stock, x-pipes, double x-pipes, single mid-pipes, or rear-section solutions, the sound waves move at the same rate upon exiting the system. This results in a higher-pitched sound that some have likened to a weed eater. Our exhaustive research and collaboration with BMW experts have revealed that equalizing the length of the exhaust pipes before mixing is the solution to this sound issue.

Initial attempts to address this variance focused on rectifying the space behind the differential housing. However, feedback revealed that it would necessitate replacing existing rear exhaust systems, which many BMW owners were reluctant to do. Leveraging our expertise in developing a single mid-pipe system for the F-series M cars, Active Autowerke redirected its research and development resources toward creating the mid-pipe solution presented here. Our team explored various approaches, ultimately extending the length of the passenger side mid-pipe section and introducing a new crossover section. This innovative design, incorporating sinusoidal pipes, allows us to correct the variance in downpipe length before merging the sounds, resulting in the exhilarating 6-cylinder sports car exhaust notes you desire.

The Active Autowerke M2C and M2CS Equal Length Mid Pipe are purpose-built to achieve equal-length exhaust pipes by compensating for the difference between the front and rear banks of the F87 S55 downpipes before incorporating an X-pipe. This results in an exhaust note distinct from the typical “S55 sound.” Engineered for a precise fit on both the F87 M2C and M2CS, the difference in sound when using this mid-pipe will be immediately noticeable, especially when unleashing the full power of your BMW.

Note: it is strongly recommended for vehicles with catless (straight-through) downpipes to opt for the resonator option when choosing the equal-length mid-pipe.

For owners of cars with aftermarket downpipes, we recommend the resonated version, although our testing has been conducted with the stock rear exhaust and Active Autowerke valved exhaust. On the M2C with the stock exhaust, there may be some rasp.

With stock downpipes, the rasp is minimal, but opting for the resonated version may still be preferable. However, if you have the M Performance Exhaust (MPE) or the CS exhaust, we highly recommend using the resonated version.

Please note that we do not guarantee results with rear exhaust systems from other manufacturers.

Key Features:

• Lighter weight than the factory system
• Quicker turbo spool
• Increased low-end and mid-range power
• Equal length design eliminates the pulsing sound caused by the unequal length down pipes

• F87 M2C Mid-Pipe-Equal Length (EL)-Resonated Install Guide
• F87 M2C Mid-Pipe-Equal Length (EL)-Non-Resonated Install Guide