Wagner Tuning BMW F-Series N20 Catless Downpipe Kit

Unlock performance, sound and spool with a high-flow de-cat turbo down pipe upgrade for BMW N20

Transform your F-Series 1 Series, 2 Series, 3 Series and 4 Series with this premium de-cat turbo outlet pipe. Built for the N20 petrol engine, it delivers freer exhaust flow, faster turbo response and a richer exhaust note once mapped. Precision CAD-developed and manufactured from 1.4301 T304 stainless for strength and longevity, it’s a direct OE swap that keeps your sensors in the correct locations and fits like factory.

Vehicle compatibility

Designed for N20-powered F-Series models from 10/2012 onwards, including xDrive where stated:

• BMW 125i F20 and F21
• BMW 220i F22 and F23
• BMW 228i F22 and F23
• BMW 320i F30, F31, F34 including xDrive
• BMW 328i F30, F31, F34 including xDrive
• BMW 420i F32 and F33
• BMW 428i F32 and F33 including xDrive

Cross-reference BMW part number: 18327645666 - replaces the OE turbo down pipe on applicable vehicles built from 10/2012+.

Why enthusiasts choose this de-cat down pipe

• Direct bolt-on replacement using factory mounting points - no cutting or welding required
• 1.4301 T304 stainless construction for durability and corrosion resistance
• Optimised, catalyst-free design for reduced back pressure and stronger midrange pull when paired with tuning
• Lower thermal load on the turbocharger for consistent performance under hard use
• Two O2 sensor bungs - keeps lambda probes in the correct locations
• Connection diameter 105 mm - main tube diameter 76 mm
• Outstanding fitment - developed to align perfectly with OE brackets and hardware

Real-world results you can feel

We run this hardware on our own N20 development cars and our customers love the improved throttle response, deeper tone and stronger pull once calibrated. It pairs brilliantly with a Stage 2 remap, intercooler and intake for a proper fast-road or track setup.

Installation, mapping and support

• Software changes are required to prevent an engine management light after catalyst removal
• Professional installation recommended for best results and alignment
• Fitting available at MJ Modifications in Warwickshire - request a quote: info@mjmodifications.co.uk

Important usage notice

Off-road or motorsport use only unless a catalyst is installed elsewhere in the exhaust system. Removing catalytic converters is likely to make your vehicle illegal for use on public roads. It is your responsibility to comply with local laws and regulations.

Looking for these upgrades

BMW 320i decat pipe - BMW 328i down pipe - BMW 125i decat - BMW 228i turbo downpipe - BMW 420i performance exhaust - BMW 428i de-cat - F20 F21 F22 F23 F30 F31 F32 F33 F34 N20 down pipe - race downpipe - turbo outlet pipe - performance de-cat for N20 engine - F30 328i decat downpipe.