Stone Exhaust BMW N13/N13B16 Catless/Decat Downpipe (Catalyst Delete Turbo Outlet/Elbow) - F20 F21 116i 118i 120i, F30 F31 316i | 1 Series & 3 Series High-Flow Performance Race De-Cat | A213P

BMW N13 Catalyst Delete Pipe for F20 F21 116i 118i 120i and F30 F31 316i | Stone Exhaust A213P

Transform throttle response and turbo spool with this high-flow catalyst delete pipe designed for the BMW N13 petrol turbo engine. Built by Stone Exhaust for the 1 Series F20 F21 116i 118i 120i and 3 Series F30 F31 316i, this performance turbo outlet upgrade reduces back pressure, sharpens mid-range punch and adds a purposeful soundtrack. It is a direct replacement that uses factory mounting points for a clean, bolt-on install.

Key advantages

• Designed specifically for BMW N13-powered 1 Series and 3 Series models: 116i, 118i, 120i and 316i
• Integrated flex joint helps manage heat cycles and vibration to minimise the risk of cracking
• Reinforced turbo flange with crisscross welds for strength and long-term reliability
• One-piece bend path promotes uninterrupted gas velocity for quicker turbo response
• Machine welding for consistent penetration and smooth internal finishes
• Developed with 3D scanning and reverse engineering for precise routing and fit
• Robotic spot welding for accuracy and repeatable quality
• OEM-style fitment for straightforward installation on the N13 turbo system

Engineered for flow and durability

Stone Exhaust maps the factory assembly with detailed 3D scanning, then refines diameter, path and bend angles to maximise flow while respecting clearances. Production uses a 7 axis CNC bending process that achieves approximately 98% roundness and limits outer bore wear to around 25% at 180 degrees. Coupled with reinforced flange welding and precise robotic spot welds, the result is a robust, high-flow de-cat pipe that installs neatly and performs consistently.

Proven on customer cars

We have run this Stone Exhaust N13 de-cat on customer vehicles and our own builds. Feedback is consistently positive on fit quality, improved response and the more assertive exhaust tone. If you want a cleanly engineered turbo down pipe solution that wakes the car up without drama, this is the one we recommend.

Compatibility

Engine: BMW N13

BMW 1 Series

• F20 116i / 118i / 120i (2010+)
• F21 116i (2011+) / 118i / 120i (2012+)

BMW 3 Series

• F30 316i (2012+)
• F30 LCI 316i (2015+)
• F31 316i (2011+)

Part number

A213P

Manufacturer and warranty

Brand: Stone Exhaust

Warranty: 2 Year Stone Exhaust Warranty

Professional fitting

Want it installed properly first time? Book expert fitting with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a quotation and availability.

Important note

This catalyst removal pipe is intended for off-road or motorsport use where permitted. Please check local regulations before purchase and installation.

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