Wagner Tuning BMW B58/B58C OPF Catless Downpipe - BMW G20 M340i, G30 540i, G29 Z4 M40i, G32 640i, G14/G15/G16 840i | Toyota GR Supra A90 | 3.5" SS304, Direct Fit, Adapter Included | Replaces 18329897313 | PN 500001037.CATLESS

Turn your B58-powered BMW or A90 Supra into a sharper, harder-hitting performer with this Wagner decat turbo front pipe for OPF cars. Built from premium 1.4301 stainless steel in a full 3.5 inch 89 mm diameter, this race-spec front section frees up exhaust flow, speeds up turbo response and unleashes a deeper, more purposeful soundtrack. It is a direct plug-in replacement for the OE front pipe and includes an adaptor to join the standard cat-back system. Part Number: 500001037.CATLESS. Replaces OE reference 18329897313.

We fit these regularly at MJ Modifications and on our own projects. Feedback from owners is consistently excellent: crisper throttle, stronger mid-range shove and a more engaging, motorsport-inspired tone. If you are searching for a proven decat solution for OPF-equipped B58C cars, this is the upgrade enthusiasts ask for.

Why enthusiasts choose this OPF decat front pipe

• 1.4301 SS304 stainless construction for durability and heat management
• True 3.5 inch 89 mm tubing for high gas velocity and reduced drive pressure
• Supplied adaptor for seamless connection to the factory mid section
• Direct bolt-on fitment for OPF models with precise alignment
• Lower thermal load on the turbocharger for improved longevity
• More headroom for tuning with freer breathing and quicker spool

Vehicle applications OPF models

• BMW G20 G21 M340i xDrive 3.0 B58C 285 kW 374 PS 2020 onward OPF
• BMW G30 G31 540i xDrive 3.0 B58C 250 kW 340 PS 2018 onward OPF
• BMW G32 640i xDrive 3.0 B58C 250 kW 340 PS 2018 onward OPF
• BMW G14 G15 G16 840i xDrive 3.0 B58C 250 kW 340 PS 2018 onward OPF
• BMW G29 Z4 M40i 3.0 B58C 250 kW 340 PS 2018 onward OPF
• Toyota GR Supra MK5 A90 3.0 B58 250 kW 340 PS 2018 onward OPF

Note: For vehicles equipped with OPF only. Removing the catalyst will cause a fault message in the DME.

Real-world benefits you can feel

Expect sharper boost build, cleaner top-end pull and a stronger, more characterful exhaust note. The free-flowing 89 mm tubing reduces back pressure, helping the 3.0 turbo straight-six breathe and respond the way it should. Ideal for mapped M340i, 540i, 640i, 840i, Z4 M40i and GR Supra builds seeking a reliable, high-flow front pipe that fits like OEM.

Fitting and installation

Professional installation recommended. For fitting at our Warwickshire workshop, contact MJ Modifications for a tailored quote: info@mjmodifications.co.uk.

Compatibility check before dispatch

We will verify fitment prior to shipping. Add your UK registration or the last 7 digits of your VIN at checkout so we can confirm it suits your exact car.

Part numbers

Manufacturer PN: 500001037.CATLESS
Replaces BMW OE: 18329897313

Brand and cover

Manufacturer: Wagner Tuning
Warranty: 2 years

Search phrases buyers use

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