PROFILE

The ARM 6" B58 Downpipe takes the title of being the largest catless downpipe available for the B58 platform!  The sound coming from your B58 with the 6" section of the ARM B58 Downpipe will astonish you.  Even deeper tones, even better sound, and improved turbo spool.  

The ARM 6" B58 Downpipe is one of the foundational upgrades for giving your B58-powered BMW more power, torque, and sound.  The stock B58 downpipe comes from the factory with a catalyst that severely restricts exhaust flow, causing excessive backpressure with increased boost.  Upgrading to the ARM 6" B58 Downpipe unlocks power, improves turbo spool, allows you to safely run stage 2+ tuning, all while improving the sound of your B58-powered BMW.