Active Autowerke Equal Length Mid Pipe with F-Brace – F8X M3 / M4 Active Autowerke

For over 41 years, Active Autowerke has been at the forefront of engineering high-quality BMW performance products. With a steadfast commitment to enhancing your driving experience, we have earned recognition as a leading innovator in the BMW community. Our unwavering philosophy centers around developing refined performance parts that cater to the discerning needs of BMW enthusiasts worldwide. In line with this ethos, we proudly present our latest research and development endeavor: the Active Autowerke F80 M3 and F82 M4 equal-length mid-pipe—a remarkable addition to our acclaimed F8X collection.

When it comes to an inline-six engine, the exhaust pulses naturally harmonize, creating a seamless and exhilarating auditory experience. However, the twin-turbo configuration of the S55 engine, while adding power, has introduced an unconventional sound that resembles two independent inline-three engines vying for attention rather than the throaty symphony one would expect. This dissonance arises from the significant difference in length between the front and rear downpipes, spanning almost a foot and a half. As a result, when these exhaust pulses merge through stock, x-pipes, double x-pipes, single mid-pipes, or rear-section solutions, the sound waves align at the same rate upon exiting the system. These crossover sections inadvertently create a higher-pitched noise, often described as an irritating “weed eater” sound. The existing systems permit the banks to merge unequally pulsed sounds, prompting an extensive research and testing process involving BMW experts. Consequently, we discovered that equalizing the exhaust pipe lengths before merging them offered a viable solution to this sound predicament.

Initial attempts to address this variance focused on rectifying the space behind the differential housing, but this presented a challenge as it required the replacement of existing rear exhaust systems. Determined to provide a solution that retained the original rear exhaust, Active Autowerke leveraged its expertise in developing single mid-pipe systems for the F-series M cars. Consequently, our dedicated research and development resources were channeled into the creation of the mid-pipe solution before you. By extending the passenger-side mid-pipe section and incorporating a new crossover segment, we achieved an exhaust note that defies the conventional “S55 sound.” Our patented crossover design, featuring sinusoidal pipes, effectively rectified the variance in downpipe length before merging the sounds, resulting in the anticipated exhaust notes of a true 6-cylinder sports car.

The Active Autowerke F8X Equal Length Mid Pipe stands as a testament to our unwavering pursuit of perfection. Meticulously crafted to establish equal lengths for the exhaust pipes, it harmonizes the front and rear banks of the F80 M3 and F82 M4 downpipes before merging them through an X-pipe. The outcome is an exhaust note that departs from the customary “S55 sound.” Engineered with precision for a seamless fit on both the F80 M3 and F82 M4, the transformative impact of this mid-pipe is immediately perceptible with the first exhilarating throttle release!

Please note that for vehicles equipped with catless (straight-through) downpipes, we strongly recommend selecting the resonator option for the equal-length mid-pipe.

While we advise owners of cars with aftermarket downpipes to opt for the resonated version, it is essential to highlight that our testing was conducted solely with the stock rear exhaust and Active MAAD MAXX exhaust. A minimal rasp is expected with stock downpipes. However, we cannot guarantee results with other brands of rear exhaust systems.

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 downpipes.

Installation Manuals

• F8x Mid-Pipe to Stock BMW Rear (Resonated)

• F8x Mid-Pipe to Stock BMW Rear (Non-Resonated)

• F8x Mid-Pipe to Stock BMW Rear (AWE)