AIRTEC Motorsport De-cat Downpipe - B58

Catless front pipe for BMW B58 3.0 turbo powertrains

Unlock sharper spool, stronger mid-range and a deeper, motorsport-inspired tone with this AIRTEC Motorsport cat delete front section for the BMW B58 straight-six. By replacing the restrictive primary catalyst in the stock turbo outlet pipe, this free-flow upgrade minimises exhaust backpressure and lets the turbo breathe, delivering faster response and headroom for tuning.

Why enthusiasts choose this B58 turbo outlet upgrade

• High-flow design for improved throttle response and torque across the rev range
• Cast turbo outlet elbow maintains full internal diameter for optimal gas speed
• Precision stainless steel construction with smooth, mandrel-style radii for efficient flow
• Supplied adaptor to mate to the factory cat-back, and compatible with most performance exhaust systems
• Ideal supporting hardware for Stage 2 software on BMW’s B58B30 engine
• Finished with AIRTEC laser-cut branding plate

Real-world results you can feel

We run this hardware on our own builds and many customer cars. Feedback is consistently positive: quicker turbo spool, a more urgent pull through the gears and a richer, sportier exhaust note without compromising day-to-day drivability. Pair it with a quality remap to maximise gains.

Vehicle compatibility

For BMW models equipped with the B58 3.0 turbo engine, including:

• F20 / F21 140i
• F22 / F23 240i
• F30 / F31 340i
• F32 / F33 / F36 440i
• G30 / G31 / G38 540i
• G32 640i GT
• G12 740i
• G01 X3 M40i
• G02 X4 M40i

Fitting and support

Professional installation recommended. For expert fitting, book in with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a tailored quote and scheduling. We also offer tuning packages and can advise on the best supporting mods for your B58 build.

Important information

This catless front pipe is intended for motorsport and off-road use only. It will not pass a UK MOT or roadside emissions inspection.

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