Wagner Tuning F-Series B58 Catless Downpipe Kit

High-flow turbo outlet for BMW M140i, M240i, 340i, 440i and 540i

Unlock serious performance on your turbocharged 3.0 straight-six with this premium de-cat front pipe. Built from high quality 1.4301 stainless steel (SS304) with a full 3.5 inch bore and a supplied connector to mate to the factory system, this upgrade delivers sharper throttle response, faster spool and a deeper, sportier exhaust note. It replaces the restrictive OEM front section to reduce back pressure and lower temperatures around the turbine housing for repeatable power on road and track.

Why enthusiasts choose this upgrade

• Proven power gains from reduced exhaust back pressure and improved flow
• Noticeably crisper turbo response and stronger mid-range torque
• Lower thermal stress on the turbo for consistent performance
• Durable 1.4301 stainless steel construction for long-term reliability
• 3.5 inch big-bore design with adapter to join the original cat-back
• Direct replacement for the factory front pipe with precise fitment

Vehicle compatibility

Designed for the following BMW models with the turbocharged 3.0 petrol engine:

• 1 Series M140i, including xDrive variants
• 2 Series M240i
• 3 Series 340i
• 4 Series 440i
• 5 Series 540i

Only suitable for cars without GPF. Not for vehicles fitted with a gasoline particulate filter.

What you get

• High-flow stainless steel front pipe, 3.5 inch diameter
• Adapter to connect to the stock exhaust system

Installation and important notes

• Direct bolt-on to the factory turbo outlet and OE cat-back when using the supplied adapter
• Removal of the catalytic converter may trigger a fault code or dashboard light without appropriate software
• Recommended for off-road, track day and motorsport use where legislation permits
• Professional fitting available with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a fitting quote

What our team and customers say

We have run this on our own builds and countless customer cars and the difference is immediately noticeable. Stronger pull, a more aggressive soundtrack and repeatable performance run after run. Fitment is spot on and the quality of the stainless steel is exactly what you want for a high temperature turbo application.

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