Remus Sport BMW F80 M3 & F82 F83 M4 Valved Rear Silencer Exhaust Back Box (S55) - Stainless Steel Axle-Back, ECE/EEC Approved, OEM Valve Control, Without Tailpipes

Valve-Controlled Rear Section for F80 M3 and F82 F83 M4 - Stainless Steel, ECE Approved, Works With Factory Flap Control

Give your S55-powered M-car the sound and response it deserves. This premium stainless steel rear section replaces the stock back box on the F80 M3 saloon and F82 F83 M4 coupe and cabriolet, delivering a richer tone, crisper throttle feel and OEM-level integration with the original exhaust flap motors. It is EU road legal with ECE type approval, so you get proper motorsport character without compromising day-to-day refinement.

Why enthusiasts choose this rear section

• Valve-controlled sound - quiet for commute, assertive when you want it thanks to direct use of the factory actuator and electronics
• Shot-blasted stainless steel construction for long-term durability and a quality finish
• Improved gas flow with 70 mm pipework vs the 65 mm original for reduced back pressure and sharper response
• Lightweight assembly compared with the standard back box
• Precision fitment with plug and play flap control, no coding required
• ECE homologated for legal road use across Europe
• Handcrafted in Austria with a 24 month manufacturer warranty

What is included

• Stainless steel rear muffler section without tailpipe trims
• Two integrated valves, designed to operate via the original valve motors
• ECE approval documentation

Fitment

• F80 M3 saloon - 2015 onward, including Competition
• F82 M4 coupe and F83 M4 convertible - 2015 onward, including Competition
• Engine: S55 twin turbo straight six

Pipework and flow

OE tubing 65 mm. Upgraded tubing 70 mm for enhanced flow and response.

Installation notes

When retaining the standard front section the original system is cut at the marked factory joint. This rear section then sleeves on and connects to the OEM valve motors for full flap functionality using the car's native controls.

Tailpipe choices to complete the look

Supplied without tips so you can tailor the finish. Compatible genuine options include:

• Stainless steel polished Ø102 mm
• Stainless steel polished rolled edge Ø102 mm
• Carbon outer with titanium inner Ø102 mm
• Stainless steel with carbon insert Ø98 mm
• Black chrome with carbon insert Ø98 mm

Build a full system

For maximum soundtrack and flow, combine this rear section with an X-pipe and centre connection tubes to create a full cat-back on your S55. Popular with drivers who want a balanced tone with valves shut and a hard-edged note with valves open.

Real-world feedback

We have installed and run this setup on customer vehicles and our own demonstrators. Owners consistently praise the deep, refined soundtrack with valves closed and the addictive bark with valves open, plus the clean fit and factory-style valve operation.

Professional fitting

Prefer expert installation. Book with MJ Modifications in Warwickshire. Request a fitting quote at info@mjmodifications.co.uk.

Compatibility check before dispatch

We verify fitment before shipping. Please provide your UK registration or the last 7 digits of your VIN at checkout.

Part number

089014 0500

Manufacturer and warranty

Manufactured by Remus and supplied with a 2 year warranty, non transferable.

Dyno and media

Dyno result on F80 M3 and F82 F83 M4:

Full system video:

Rear section with equal-length mid-pipe:

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