OKTAN
BMW S55 Downpipes — F80 M3 / F82·F83 M4 / F87 M2 Competition
Lower driver-side corner of the windscreen, the sticker in the driver’s door jamb, or your registration / insurance card. It’s 17 characters — we decode it instantly and never store it.
- Custom-made to order — ships in 10–14 days
- Free tracked shipping across the USA
- Secure payment
- Fitment guarantee — we confirm before you buy
Catless vs 200-cell — which configuration?
| Catless | 200-Cell High-Flow | |
|---|---|---|
| Airflow | Maximum | Excellent |
| Sound | Loudest, most aggressive | Aggressive, less raspy |
| Check-engine light | Needs a tune to clear | Usually code-free on a tune |
| Street & emissions | Off-road / competition only | Far more street-friendly |
| Best for | Track & max-power builds | Daily drivers wanting more |
Emissions & off-road notice. Catless configurations are sold for closed-course competition and off-road use only and are not legal for street use on pollution-controlled vehicles. You are responsible for compliance with the emissions laws where you drive. Prefer a street-friendly setup? Choose a 200-cell high-flow configuration above.
Fitment: 2015–2018 BMW M3 (F80), M4 (F82/F83) & M2 Competition (F87) — S55 twin-turbo 3.0L
Precision mandrel-bent stainless steel catless downpipe, TIG-welded with CNC-machined flanges for a factory-fit bolt-on. Removing the restrictive OEM cat frees exhaust flow for faster spool, a deeper note, and meaningful power once tuned.
- Mandrel-bent stainless steel — corrosion & heat resistant
- Direct bolt-on, OEM-location flanges & hangers
- Best paired with a supporting tune to clear codes and unlock gains
- See the engine-specific fitting walkthrough in The Garage
Catless / de-cat design — intended for off-road & competition use only. You are responsible for emissions compliance where you drive.
Install at a glance
- Let the exhaust cool fully, then raise and support the car on stands or ramps.
- Soak the fasteners and O2 sensors with penetrating oil before removal.
- Transfer your O2 sensors to the new pipe — OEM sensor positions are retained.
- Seat the flange and tighten the V-band clamp evenly, then torque to spec.
- Running catless? Pair it with a supporting tune to manage fuel trims and the CEL.
- Every order is fitment-confirmed before it ships — stuck? We’ll walk you through it.