High Flow Race Downpipe For B9 B9.5 Audi S4 & S5 3.0T | ARM MotorsportsThe ARM B9 S4 catless Downpipe is one of the best upgrades for the Audi 3. 0T EA839 engine, found in the B9 S4 and S5! The ARM B9 3. 0T Downpipe allows for more exhaust flow from the turbocharger which allows your 3. 0T to spool faster, increasing throttle response, and boosting power and torque. On top of all of these performance benefits, the ARM B9 3. 0T Downpipe upgrade opens up the sound of your 3. 0T especially when paired with the ARM B9