The ARM F87 M2 Competition Downpipes are built to do three things at once: maximize power and torque, fit perfectly, and sound extraordinary on your S55. Beyond a basic Stage 1 tune, the OEM catalysts choke the S55's turbos under higher boost — raising back-pressure, making the turbos work harder, and shortening their life. These downpipes relieve that pressure so the exhaust flows freely, adding power and torque while extending turbo longevity.Highlights Up to +30whp / +30wtq Enhanced exhaust note 304 stainless steel Improved turbo spool Proven on the dynoOn our test car, fitting these downpipes and switching to a Stage 2 flash produced 543whp and 547wtq — a gain of 73whp and 126wtq over the stock results. Even on a stock tune with the resonated version installed, you'll feel more power, torque, and responsiveness, plus the head-turning sound only an S55 makes at part and full throttle.Rumble, not raspThe resonated S55 downpipes give your M2 Competition a deep, aggressive tone that stands apart from the high-pitched rasp common to catless setups. The 4" resonators are positioned to enhance sound without compromising fitment. Prefer to keep emissions in check? Opt for the catted version, which swaps each resonator for a 200-cell catalyst.ConstructionPrecision CNC-machined v-band flanges deliver a smooth transition from the turbos into the 3" SS304 downpipe bodies, which thread cleanly through the tight space BMW leaves toward the midpipe. Where most downpipes reduce abruptly to meet the 2.5" OEM midpipes — creating turbulence — the ARM downpipes use a smooth, gradual 3" to 2.5" transition for optimum flow.In the box ARM F87 M2 Competition Resonated Downpipes CNC-machined bracket for the front-turbo downpipe 4x downpipe-to-midpipe bolts and nuts ARM lifetime replacement warranty Fitment Make Model Submodel Engine BMW F80 M3 S55 3.0L BMW F82 M4 S55 3.0L BMW F83 M4 S55 3.0L BMW F87 M2 Competition S55 3.0L Backed by ARM Motorsports' lifetime warranty against defects in craftsmanship and fitment.Emissions disclaimer: This product is not legal for sale or use on pollution-controlled vehicles operated on public roads and is intended for off-road, race, or closed-course competition use only. You are responsible for compliance with all applicable emissions laws; use on public roads may violate the Federal Clean Air Act (42 U.S.C. § 7522) and similar state laws. Please check your local laws before purchase and installation.Ships from our Vancouver shop — KORE SPEED is proudly Canadian-owned, with no surprise cross-border duties for Canadian buyers. Questions on fitment? Email [email protected].