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JHM 2.75" Performance Exhaust - Valved - Downpipes and Cat-Back (JHM) for B8-RS5 4.2L

This is a Race-only product. By adding this product to your shopping cart, you are electronically acknowledging that this product is not to be installed on any registered vehicle that will be driven on any US road, street or highway. In addition, you also acknowledge that the use or installation of this product outside of the intended closed circuit racing purpose may be illegal under the Federal Clean Air Act (42 U.S.C. § 7522(A)(3))

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Track Car Modification Waiver Form

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The JHM 2.75" full exhaust system represents the latest in development efforts from the 4.2L V8 experts at JHM. Featuring 2.75" stainless steel construction throughout, this exhaust is sure to leave a grin on your face as you floor the gas pedal on your favorite backroad. This exhaust includes downpipes, and a catback section featuring JHM's specially designed X-pipe section.

Why 2.75 Inch piping diameter? After much research, calculations, testing and development JHM found that based on the 4.2L 32v V8 engine's demands, 2.75 Inch piping diameter is the optimal size. With a 2.5 inch exhaust you end up choking off the RS5's free spinning and high-revving V8. JHM has also found with a 2.75 inch cat back that torque is not sacrificed for power gains in the top end of the RPM band.

Why an X-pipe? Naturally Aspirated V8s always make more power with an X-pipe. The location and size of the X-Pipe in the JHM B8-RS5 Cat-Back Exhaust System has been meticulously researched and developed to produce the best scavenging of the exhaust pulses coming from either side of the motor. The location of the JHM X-Pipe also gives the 32-valve V8 motor a cleaner, more refined tone.

Gasket Matched Flanges: The stock headers on the B8-RS5 are a LARGER diameter than the stock downpipes. This creates a flow restriction and hinders performance.  This is because the exhaust gas is forced into smaller diameter piping. Additionally, this transition from larger to smaller diameter piping is not a smooth transition. The smaller diameter of the stock downpipes introduces a wall that the exhaust gasses must first run into before being able to transition creating turbulence. With the JHM Gasket Matched Flanges and larger diameter of the JHM 2.75" exhaust piping, there is no longer a hindrance in exhaust flow allowing optimal exhaust flow for optimal performance gains.

JHM Downpipe and Cat-Back Weight: The full weight of the exhaust system for the B8 RS5, downpipes and cat-Back is 69lbs. The stock OEM downpipes and cat-back weight 78lbs.


  • 2008-2015 Audi B8/B8.5 RS5

The downpipes in this system retain the use of the factory catalytic converters.

More Information
Brand JHM
Stock Type N/A
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