Milltek Sport Cat-Back GPF-Back Exhaust for BMW 1 Series M140i F20/F21 LCI (3 & 5 Door, OPF/GPF) 2019+ - Non-Resonated Race with Carbon Fibre Jet-90 Tips

Turn up the drama on your BMW M140i F20 F21 LCI OPF with a UK-built performance rear system from Milltek

Give your B58-powered 1 Series the soundtrack and response it deserves. This Milltek performance system replaces the pipework from the particulate filter rearwards and retains the factory OPF/GPF, delivering a harder-edged tone, crisper throttle pick-up and a premium motorsport look thanks to the carbon Jet-90 tailpipes. Hand finished in Britain from high-grade 304 stainless steel, it bolts to the original mounting points for a precise fit and lasting quality.

What you will love

• Race-volume, non-res centre design for the loudest Milltek option on OPF-equipped M140i models
• Carbon Jet-90 finish tailpipes for a bold, performance aesthetic
• 304 stainless construction with smooth mandrel bends for improved flow and sharper response
• Larger bore than stock to reduce back pressure while maintaining usable mid-range torque
• Developed specifically for the B58 engine to deliver a deep idle, aggressive acceleration note and clean turbo whistle
• Refined on-road manners with minimal cabin boom when cruising
• Direct-to-OE hangers and hardware for hassle-free installation
• Designed and manufactured in the UK by Milltek for consistency and durability

Sound and driving feel

This loud configuration is the go-to choice if you want maximum presence from your OPF M140i without removing the filter. Expect a deeper tone at idle, a more urgent voice under load and a sharper overrun character that complements the B58. The freer-flowing layout helps the engine rev more willingly and enhances pedal response for daily use and spirited drives.

Compatibility

• BMW 1 Series M140i 3-door and 5-door
• Chassis: F20 and F21 LCI
• Model years: 2019 onward with OPF/GPF
• Configuration: GPF-back system with carbon tailpipe finishers, loud non-res centre

Built to last

Milltek’s use of high-spec 304 stainless steel, precision mandrel bending and quality welding resists corrosion and discolouration for long-term reliability. The attention to detail in every bracket and joint means dependable fitment and performance.

Fitted by specialists

We have installed this exact system on multiple customer cars and on our own builds. Feedback on sound quality, finish and fit has been excellent. For professional fitting, book with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

Why buy from MJ Modifications

• Trusted Milltek supplier and installer with hands-on M140i experience
• Honest advice on sound levels and daily drivability
• In-house fitting and aftercare for complete peace of mind

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