ARM Motorsports S58 CATTED DOWNPIPES - G80 M3 G82/G83 M4

The ARM S58 Catted Downpipes unlock significant performance gains for your BMW G80 M3, G82/G83 M4, or G87 M2 by reducing exhaust backpressure and allowing the twin turbos to spool faster. This upgrade improves throttle response, increases power delivery throughout the RPM range, and enhances the overall driving experience—making it one of the most effective hardware upgrades for the G8X and G87 platforms.

By replacing the restrictive factory catalysts, the downpipes allow your S58 to reach target boost quicker, resulting in improved acceleration and noticeably faster 0–60 and quarter-mile times. Vehicles running upgraded tunes benefit even more, as reduced backpressure is essential when running elevated boost levels beyond OEM specifications.

The ARM S58 Catted Downpipes also transform the sound profile of the S58. Expect increased exhaust volume, sharper burbles, and more pronounced turbo spool—even on factory software. The tone becomes more exotic while retaining OEM fitment and compatibility with stock or aftermarket midpipes.

Constructed from durable SS304 stainless steel, each set begins with a CNC-machined 3" turbo v-band flange. Depending on configuration, the downpipes feature either a resonated catless design or a high-flow 200-cell catalytic converter. The resonators used in the catless version are hollow and offer zero restriction while refining exhaust tone. The catted version offers similar sound characteristics while helping reduce exhaust odor but may still trigger a check-engine light without tuning or a CEL-delete solution.

The longer front downpipe incorporates a reinforced flex section to relieve stress on the turbo during aggressive acceleration, cornering, or braking. Both downpipes transition to a 2.75" two-bolt outlet to ensure perfect compatibility with OEM and aftermarket midpipes designed for OEM downpipe fitment.

Fitment:
• BMW G80 M3 – S58 3.0L
• BMW G80 M3 Competition xDrive – S58 3.0L
• BMW G82 M4 – S58 3.0L
• BMW G82 M4 Competition xDrive – S58 3.0L
• BMW G83 M4 – S58 3.0L
• BMW G83 M4 Competition xDrive – S58 3.0L
• BMW G87 M2 – S58 3.0L