S58 CATTED DOWNPIPES - G80 M3 G82/G83 M4

The ARM S58 Catted Downpipes increase power and torque on your G8X while unleashing an exotic exhaust note — one of the best all-around hardware upgrades for the platform, with no need to replace the whole catback. By reducing back-pressure on the S58's turbos, they spool faster and hit boost quicker for more power sooner. The benefit grows once you tune, as back-pressure climbs above OEM boost.

Highlights

• Increased power and torque.
• Faster turbo spool.
• Exotic exhaust sound and louder burbles, even on OEM programming.
• SS304 stainless steel.

Construction & options

Built from SS304 with a 3" precision CNC-machined turbo V-band flange. Choose your configuration:

• 200-cell catted: high-flow catalysts sound very similar to catless while reducing exhaust odor (may still trigger a CEL; clear with a tune or CEL Delete Kit).
• Catless Resonated: hollow resonators (no obstruction) tune a strong, aggressive tone while maximising flow.

The longer front downpipe uses a reinforced flex section to relieve turbo stress, and both transition to a 2.75" 2-bolt connection that mates to OEM or aftermarket midpipes.

Fitment (S58 3.0L)

BMW G80 M3, G82 M4, G83 M4 (incl. Competition xDrive), G87 M2.

What's included: ARM S58 catted downpipes, midpipe connection mounting hardware.

Backed by ARM Motorsports' lifetime warranty against defects in craftsmanship and fitment.

Emissions disclaimer: This product is intended for off-road, race, or closed-course competition use only and is not legal for use on pollution-controlled vehicles operated on public roads in most states and provinces. You are responsible for compliance with all applicable emissions 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 support@korespeed.com.