BMW M340i OPF Decat Downpipe – also fits 440i, 540i, 640i, 740i, 840i, Z4 M40i and Toyota Supra A90 GR with OPF/PPF
Unlock the full potential of your B58 engine with our 4.5 inch stainless steel OPF decat downpipe. Designed for G series BMW and Toyota Supra A90 OPF models, this B58 decat downpipe dramatically improves turbo response, increases power and transforms the exhaust note. Built from SS304 stainless steel and TIG welded in house, it is a premium upgrade for enthusiasts who want the best performance and sound from their M340i, 440i, 540i, 640i, 740i, 840i, Z4 M40i or Supra A90.
Why choose this B58 OPF decat downpipe
- 4.5 inch stainless pipe straight out of the turbo for faster spool and sharper throttle response
- Constructed from SS304 aircraft grade stainless steel, TIG welded for strength and durability
- Mandrel bent for smooth gas flow and maximum internal diameter to deliver ultimate performance without losing mid range torque
- Reduces exhaust backpressure and temperatures to relieve the turbocharger and increase cylinder charge
- Noticeable power gains with a much more aggressive exhaust note that sounds incredible
- Significant weight saving compared to the restrictive factory catalytic converter
We have tested this product and found increases of around 20 to 25 bhp. We have fitted this downpipe to numerous customer cars and feedback has been consistently positive on performance, drivability and sound.
Fitment – OPF/PPF models only
This BMW B58 OPF decat downpipe fits the following models with OPF/PPF only:
- BMW G20/G21 M340i 3.0L 285 kW / 374 PS 2019 OPF model
- BMW G22 440i 3.0L 285 kW / 387 PS 2019 OPF model
- BMW G30/G31 540i 3.0L 250 kW / 340 PS 2018 OPF model
- BMW G32 640i 3.0L 250 kW / 340 PS 2018 OPF model
- BMW G11/G12 740i 3.0L 240 kW / 326 PS 2019 OPF model
- BMW G14/G15/G16 840i 3.0L 250 kW / 340 PS 2019 OPF model
- BMW Z4 G29 M40i 3.0L 250 kW / 340 PS 2019 OPF model
- Toyota Supra MK5 A90 GR 3.0L 250 kW / 340 PS 2019 OPF model
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Fitting and installation
- Professional installation recommended. Tolerances can vary between exhaust systems and space can be tight, though feedback suggests this downpipe is straightforward to fit.
- Please swap the gasket at the turbo end of the downpipe. Failure to do so can result in a fuel smell in the cabin.
- We recommend using a Lambda Sensor Spacer to help prevent the engine light in most cases. Search our other items for suitable spacers.
Want it fitted by specialists We can help. Nforcd is based in Warwickshire. Request a fitting quote at Sales@nforcd.com.
Why this BMW B58 OPF de cat downpipe is a must have
If you are looking for a BMW M340i downpipe or a B58 decat downpipe that delivers real gains, this 4.5 inch stainless steel OPF downpipe is the ultimate choice. Expect faster turbo spool, improved throttle response, a deeper and louder exhaust note and proven power increases. The combination of SS304 stainless construction, TIG welding and mandrel bends ensures durability and maximum performance for your G series BMW or Toyota Supra A90 GR.
Order your BMW M340i OPF decat downpipe today and transform the way your B58 powered car drives and sounds.