Scorpion Valved Axle-Back/Back Box Exhaust for BMW 1 Series M140i F20/F21 (2018-on GPF/PPF) — OEM Flap Control, 80mm Bore, Ascari 100mm Tips — Rear Silencer/Muffler Upgrade — SBMS082CF

BMW M140i F20/F21 2018-on PPF rear exhaust upgrade with OEM flap control — Part SBMS082CF

Unlock a richer soundtrack and a lighter, sharper-feeling drive on your BMW 1 Series M140i hatchback with this premium rear section upgrade from the petrol particulate filter backwards. This valved performance exhaust retains factory electronic flap control for civilised cruising and an engaging tone on demand, and it finishes the rear of the car with striking Ascari 100 mm tips.

We’ve fitted this upgrade to customer M140i cars and the feedback has been superb: refined when you need it, and purposeful when you want it. Fit, finish and alignment are top drawer, and the weight saving over the standard assembly is immediately noticeable.

Why enthusiasts choose this upgrade

• Made for 2018-on petrol particulate filter models of the M140i (F20 5-door and F21 3-door).
• Factory-controlled valve uses the original actuator for seamless integration.
• Large-bore 80 mm tubing (3.15 inch) for excellent flow characteristics.
• Ascari 100 mm tailpipe finishers for a bold, motorsport-inspired look.
• Significant weight reduction: approx. 10.9 kg vs. 15.5 kg original (around 4.6 kg lighter).
• Joins to the stock system; installation involves trimming the original rear section.
• Compatible with OEM and full-brand systems where applicable.

Fitment and compatibility

• Vehicle: BMW M140i F20/F21, 2018 onwards with petrol particulate filter (PPF/GPF).
• Valve operation: reuses the OE motor/actuator.
• Connection method: cut-and-join to the factory pipework as per the manufacturer’s instructions.
• Part number: SBMS082CF.

The sound and drive you want

With the flap shut you get an easy-going, comfortable drive suitable for daily use. Open the valve and enjoy a deeper, sportier note that lets the B58 sing. The larger bore reduces restriction compared to stock, and the weight saving helps the rear of the car feel that bit more responsive.

Professional installation available

For fitting, we recommend booking with MJ Modifications in Warwickshire. Our experienced team has installed this upgrade on numerous M140i models. Request a fitting quote: info@mjmodifications.co.uk.

Key specifications

• Bore size: 80 mm / 3.15 inch
• Tailpipe style: Ascari, 100 mm
• Weight: OE approx. 15.5 kg, upgrade approx. 10.9 kg
• Notes: requires reuse of the original valve motor; cutting of the factory system is required for installation

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