Milltek GPF/OPF Bypass Large Bore Downpipes with High Flow Sports Cats for BMW M4 F82 F83 and M4 Competition OPF models 2019 to 2020 - Part No. SSXBM1127
Unlock the sound and performance your BMW M4 deserves with Milltek’s GPF/OPF bypass large bore downpipes and high flow sports cats. Designed, developed and hand-finished in the UK, this premium Milltek Sport upgrade delivers freer-flowing exhaust gas movement, sharper response and a deeper, crisper exhaust note without harsh cabin drone. Perfect for BMW M4 owners seeking a high quality downpipe and OPF bypass solution that fits, performs and lasts.
Why choose Milltek SSXBM1127 for your BMW M4
- Made in the UK from aerospace-grade type 304 non-magnetic stainless steel for exceptional durability and corrosion resistance
- Mandrel-bent large bore pipework for optimised gasflow and reduced backpressure
- High flow sports cats combined with OPF/GPF bypass for maximum exhaust efficiency
- Acoustically developed for a sporty, refined tone without NVH, drone or unwanted cabin resonance
- Precision fitment for BMW M4 OPF-equipped models with quality hardware throughout
Real results you can feel
We have supplied and fitted this Milltek system for BMW M4 customers and the feedback has been fantastic. Expect faster spool, improved throttle response and a stronger, motorsport-inspired soundtrack. Milltek’s enlarged bore and expertly engineered bends ensure ultimate flow while maintaining excellent drivability and mid-range torque.
Compatibility
- BMW M4 F82 Coupe OPF/GPF models only - 2019 to 2020
- BMW M4 F83 Convertible OPF/GPF models only - 2019 to 2020
- BMW M4 Competition Coupe OPF/GPF models only - 2019 to 2020
- Milltek Part Number: SSXBM1127
Built to perform, built to last
Every Milltek system is produced using high grade type 304 stainless steel and hand-finished by time-served craftsmen. Mandrel bending maintains a constant radius throughout, preserving flow and performance. Bore diameters are carefully enlarged over stock to unlock power without sacrificing tractability. The result is a premium, UK-engineered exhaust upgrade that sounds right and stands the test of time.
Fitting and support
Professional installation recommended. Nforcd offers in-house fitting in Warwickshire and full aftercare support. For a fitting quote or advice, contact Sales@nforcd.com.
Notes and usage
This product is designed for OPF/GPF-equipped models only. Check local laws and compliance requirements. Intended for off-road or track use where regulations allow.
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