Milltek GPF/OPF Bypass for BMW 5 Series M5 4.4l Twin Turbo Hybrid G90 & G99 (UK/European Spec Vehicles) (2025 onwards) – Filter Delete, Motorsport Use
This is Milltek's GPF/OPF bypass pipe for the BMW 5 Series M5 4.4l Twin Turbo Hybrid G90 & G99 (UK/European Spec Vehicles). It replaces the section of pipe housing the factory petrol particulate filter with a straight-through pipe, clearing the last major restriction left in a modern turbocharged petrol exhaust once a de-cat and remap are already in place. It's offered in fits to milltek axle back and OE downpipes only requires ECU coding or remap or fits to OE axle back and downpipes only requires ECU coding or remap OE requires cutting versions, so you can pick the setup that suits how the car's used.
It's aimed at owners already running a de-cat and a supporting remap who want to clear the final restriction in the system, not a bolt-on for a car that needs to stay road legal.
Because it removes the particulate filter, it's intended for off-road and competition use. A car with the GPF/OPF removed will fail an MOT emissions test and isn't legal to use on UK roads.
Specifications
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System Type: GPF/OPF Bypass
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Pipe Diameter: 80mm (3.15")
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EC Approved: No
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Race System: Yes
Key Features
- Made from T304L aircraft-grade stainless steel, which is anti-magnetic and resists discolouration
- Mandrel-bent pipework keeps a constant diameter through every bend for unrestricted flow
- 80mm (3.15") pipework
- Straight-through pipe in place of the factory petrol particulate filter (off-road and competition use only)
- Designed, developed and manufactured in the UK by Milltek Sport
Fitment
- BMW 5 Series M5 4.4l Twin Turbo Hybrid G90 & G99 (UK/European Spec Vehicles) (2025 onwards)
Not suitable for: the BMW 5 Series M5 & M5 Competition 4.4l Twin Turbo F90 LCI (OPF/GPF Equipped Cars), which needs the Milltek GPF/OPF Bypass BMW 5 Series M5 & M5 Comp 4.4l Twin Turbo F90 LCI OPF/GPF 21+; the BMW 5 Series M5 & M5 Competition 4.4l Twin Turbo F90 (Non OPF/GPF Cars), which needs the Milltek GPF/OPF Bypass BMW 5 Series M5 & M5 Comp 4.4l Twin Turbo F90 OPF/GPF 20-21.
Installation
Some versions: Fits to Milltek Axle Back and OE Downpipes Only - Requires ECU Coding or Remap. Some versions: Fits to OE Axle Back and Downpipes Only - Requires ECU Coding or Remap - OE requires cutting. This work involves removing parts close to the turbo and engine, so we recommend fitting by a specialist with a ramp and suitable software support.
Upgrade Further
Also available from Milltek for this car: Milltek Axle Back Exhaust BMW 5 Series M5 4.4l Twin Turbo Hybrid G90 & G99 UK & European Spec Vehicles 25+.
Does it fit the BMW 5 Series M5 & M5 Competition 4.4l Twin Turbo F90 LCI (OPF/GPF Equipped Cars)?
No. For that car, choose the Milltek GPF/OPF Bypass BMW 5 Series M5 & M5 Comp 4.4l Twin Turbo F90 LCI OPF/GPF 21+.
Is it road legal?
No. Removing the particulate filter means the car will fail an MOT emissions test, so it is for off-road and competition use only.
Do I need a remap?
Yes. Milltek notes: "Fits to Milltek Axle Back and OE Downpipes Only - Requires ECU Coding or Remap". Without suitable software the engine management is likely to log faults.
Can I use it with my standard exhaust?
Yes. Milltek lists it for use with the factory (OE) exhaust system.
What is it made from?
T304L aircraft-grade stainless steel, which is anti-magnetic and resists discolouration better than lower grades.
Is there a warranty?
Yes. Milltek products are covered against defects in materials and workmanship. Contact us with your order number if you have a problem.
