Remus Valved Axle-Back Exhaust / Rear Silencer Back Box for BMW M5 F90 Competition (2018+, S63) - Quad Carbon 102mm (4") Angled Tips, Titanium Internals - OPF/GPF Compatible, Retains OEM Valve Control - Stainless Steel Performance Muffler Upgrade

Unleash the soundtrack of your BMW M5 F90 Competition

Upgrade the rear section of your BMW M5 F90 Competition (2018 onwards, S63B44B, 460 kW) with a premium valved axle-back system featuring quad carbon fibre 102 mm angled outlets and titanium internals. This precision-built performance exhaust keeps your factory valve control fully functional for effortless switchable volume and refined manners on the motorway, with a ferocious motorsport tone when you want it.

Hand crafted in Austria from full stainless steel with a shot-peened finish, this lightweight back box delivers improved gas flow, reduced restriction and a deeper, richer V8 note without drone. The fit is spot on, installation is straightforward, and the carbon tips complete the look with an unmistakably high-end finish.

Why enthusiasts choose this upgrade

• Valved design retains factory control for quiet cruising and aggressive sound on demand
• Quad 102 mm angled carbon fibre tailpipes with titanium inner construction for a race-bred aesthetic
• Full stainless steel build with shot-blasted surface for longevity and corrosion resistance
• Improved flow characteristics and reduced back pressure for sharper response
• Lighter than stock and engineered for a precise, bolt-on fit
• Handmade in Austria for outstanding quality and consistency

Fitment and technical details

• Vehicle: BMW M5 F90 Competition, 2018 onwards, S63B44B
• Compatibility: Only for cars equipped with GPF/OPF
• Pipework diameter: 84 mm
• Tailpipes: 4 x 102 mm carbon fibre, angled cut, titanium internals
• Valve operation: Uses the factory valve control system
• Part number: 089618 0500LR+0446 70CS

Real-world results

We have fitted this system for customers and the feedback has been superb: deeper tone at idle, crisp bark under load and a classy finish that elevates the rear of the car. The OE valve integration keeps it civilised for daily use while unlocking the M5’s true character when opened up.

Installation and support

Want it fitted professionally? Book your install with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a quote and availability.

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Note: Only suitable for vehicles with GPF/OPF. If you are unsure on compatibility, contact us with your registration or VIN.