N20 Downpipe - F30 320i/328i

The ARM N20 Downpipe is the best hardware upgrade for getting the most power from your 320i or 328i. The stock N20 downpipe uses a catalyst that drastically restricts exhaust flow — limiting power on the stock tune and blocking Stage 2 due to excessive back-pressure. Upgrading unlocks power, improves turbo spool, enables Stage 2+ tuning and opens up the exhaust note.

Highlights

• Gains of up to 17 whp / 25 wtq (Stage 1).
• Faster turbo spool and improved exhaust note.
• Enables Stage 2+ tuning.
• SS304 stainless steel.

Construction

Mandrel-bent SS304 starting with a 4" precision CNC-machined turbo V-band connection that gradually reduces to 2.5" to optimise flow while matching the stock midpipe. Two mounting points reduce turbo stress from shifting and twisting, and two O2 sensor bungs retain the factory sensors (a tune or CEL Delete is required to avoid a check-engine light). On ARM's 328i, a Stage 1 tune yielded 17 whp / 25 wtq, and Stage 2 added a further 13 whp / 12 wtq — 30 whp / 38 wtq total over Stage 1.

Fitment (N20 2.0L)

BMW F22/F23 228i, F30/F31/F34 320i & 328i, F32/F33/F36 428i, F10 528i (incl. xDrive).

What's included: ARM N20 downpipe.

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.