BMW 2010-2013 E8x 135i, E9x 335i N55 Downpipe

The ARM E-Series N55 Downpipe is designed to increase power and performance of your N55 equipped BMW by optimizing exhaust flow and reducing back pressure. Upgrading the downpipe on  your N55 increases power, improves turbo spool, and allows you to run stage 2+ tuning, all while making your 135i or 335i sound better.  The ARM N55 Downpipe is compatible with OEM and aftermarket midpipes, designed for a direct fit with the 80mm V-Band flange that accommodates both standard and upgraded turbo setups.  An N55 downpipe upgrade is the first hardware upgrade every N55 owner should invest in for more power!    HIGHLIGHTS • Gain up to 21whp/27wtq• Faster Turbo Spool• Improved Exhaust Sound • Upgrade to Stage 2+ Tuning • SS304 Stainless Steel    IMPROVED EXHAUST SOUND In addition to helping your N55 make more power and torque, the ARM N55 Downpipe significantly improves the exhaust sound.  Thanks to it's 4.5" middle section, the ARM N55 Downpipe will produce a deeper and more aggressive