AIRTEC Motorsport De-Cat Downpipe for BMW B58 Engine
Unlock the full potential of your BMW B58 with the AIRTEC Motorsport de-cat downpipe. By removing the restrictive OEM catalytic converter from the factory downpipe, back pressure is significantly reduced, turbo spool is faster and throttle response is sharper, delivering increased performance and a more aggressive, motorsport-inspired exhaust note. This is the must-have BMW B58 downpipe upgrade for those chasing real gains from their 140i, 240i, 340i, 440i, 540i, 640i, 740i, X3 M40i or X4 M40i.
Supplied with an adaptor to mate to the original exhaust system, this AIRTEC de-cat downpipe also fits most aftermarket cat-back systems, making it a simple, direct replacement for the OEM downpipe and an ideal foundation for further tuning. Pair with a quality remap for even greater results.
Why choose the AIRTEC B58 de-cat downpipe
- One of the only manufacturers offering a cast elbow to retain diameter for maximum flow
- Stainless steel construction for strength and durability
- Smooth, mandrel-style bends to optimise gas flow and reduce back pressure
- AIRTEC laser-cut plaque and quality finish
- Direct fit to OEM and most aftermarket exhaust systems using the supplied adaptor
- Improved response and power potential, further enhanced with a remap
Real-world results from Nforcd
We have installed this AIRTEC B58 de-cat downpipe on customer cars and the improvements speak for themselves. Faster spool, a crisper throttle and a deeper, more purposeful exhaust tone. Our customers have been delighted with the transformation and how well it complements a remap and other supporting performance modifications.
Compatible BMW models
Fits the following BMW B58-powered models:
- F20/F21 - 140i (also commonly referred to as M140i)
- F22/F23 - 240i (also commonly referred to as M240i)
- F30/F31 - 340i
- F32/F33/F36 - 440i
- G30/G31/G38 - 540i
- G32 - 640i GT
- G12 - 740i
- G01 - X3 M40i
- G02 - X4 M40i
Perfect search terms
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Fitting and support
Professional installation recommended. For fitting, speak to Nforcd in Warwickshire. Request a quote at Sales@nforcd.com and our team will be happy to help.
Important information
De-cats are sold for motorsport and off-road use only and will not pass a UK MOT or police roadside checks.