The ARM Motorsports 3" Midpipes for the Audi B9/B9.5 S4 and S5 are engineered to dramatically improve exhaust flow and sound on the EA839 3.0T engine. Featuring a full 3-inch design through 93% of their length—compared to the OEM 2.3-inch (60mm) piping—these midpipes unlock a deeper, richer, and more aggressive exhaust tone while boosting overall performance.

By removing the factory front resonators, these midpipes allow the engine’s natural harmonics to shine, producing a sound that is crisp, powerful, and significantly more pronounced in Dynamic mode. With the OEM exhaust valves retained, you can still enjoy quiet operation in Comfort or unleash the full volume when desired.

For maximum performance and the most dramatic sound transformation, pair the ARM 3" Midpipes with the ARM B9 3.0T Downpipe. Together, they eliminate the largest restrictions in the factory exhaust, improving turbo spool, reducing back pressure, and enhancing throttle response.

These midpipes offer a fully reversible, bolt-on solution requiring no cutting, trimming, or welding. Whether paired with the OEM exhaust (using the included reducers) or an aftermarket 3" cat-back, the ARM 3" Midpipes fit perfectly and install in only 60–90 minutes.

Construction:

The ARM B9/B9.5 Midpipes begin with CNC-machined 3-bolt downpipe flanges, each equipped with a pre-installed hard-to-reach bolt to simplify installation. The system expands immediately to 3-inch mandrel-bent stainless steel piping, providing significantly improved flow compared to the OEM midpipes.

OEM-quality flex sections are integrated into each pipe to relieve stress on the downpipes during aggressive driving. Factory-location exhaust hangers ensure proper support and stability. At the rear, included reducers taper the system back to the OEM 2.3-inch size, allowing seamless compatibility with the stock exhaust. Removing the reducers enables direct connection to any 3-inch aftermarket exhaust system.

Designed for durability, flow, and ease of installation, the ARM Midpipes deliver a premium, high-performance solution for Audi 3.0T enthusiasts.

Fitment:

Fits the following Audi B9 and B9.5 models equipped with the EA839 3.0T engine:

• Audi B9 S4 3.0T
• Audi B9.5 S4 3.0T
• Audi B9 S5 Coupe 3.0T
• Audi B9 S5 Sportback 3.0T
• Audi B9.5 S5 Coupe 3.0T
• Audi B9.5 S5 Sportback 3.0T