Mini (Mk3) Cooper S / JCW (F56 LCI) Facelift 3" Valved Cat Back Performance Exhaust

Turn your MINI into the car it should have been from the factory. This UK-built switchable 3 inch stainless catback unleashes serious sound, quality and flow on the Mk3 MINI Hatch F56 LCI, covering both Cooper S and John Cooper Works models.

Crafted from premium T304 stainless with full TIG-welded construction and smooth mandrel bends, this rear system replaces the centre section and back box for freer breathing and a richer soundtrack. The integrated valve is controlled by the supplied remote fob so you can swap between a discreet cruise tone and a louder, more engaging soundtrack at the touch of a button. Choose resonated for a refined note or non-resonated for maximum volume and character.

Why MINI owners love this upgrade

• Switchable sound on demand via remote key fob, from subtle to aggressive
• 3 inch, 76.2 mm pipework for improved gas flow and throttle response
• Deep, sporty tone with authentic pops and crackles when the valve is open
• British-made T304 stainless steel, precision TIG-welded for durability
• Resonated and louder non-res options to suit your taste
• Available with carbon fibre or ceramic-coated black tailpipes for a premium finish
• Designed to pair with high-flow sports cat or decat front section for a complete turbo-back upgrade
• All required gaskets and fittings included

Sound and testing

With the flap open the tone is deeper and more pronounced. Independent 4,000 rpm track testing recorded approximately 92.4 dB with the valve open and 88.1 dB with it closed, delivering genuine dual-personality manners for daily driving and weekend blasts.

Built to perform

• Material: T304 stainless steel throughout
• Welding: TIG for strength and a clean finish
• Pipe size: 3 inch, 76.2 mm mandrel-bent for smooth flow
• Configuration: Cat-back, replaces centre and rear sections
• Control: Remote-operated valve with supplied key fob

Compatibility

Suitable for MINI Mk3 F56 LCI facelift Cooper S and JCW hatchback applications. For PPF, GPF or OPF-equipped vehicles, basic engine calibration is required at installation to prevent an EML. Use of decat or certain configurations may be for motorsport or off-road use only.

Real-world feedback

We have fitted this setup on customer cars and on our own demonstrators. The verdict is consistent: stronger tone, sharper response and top-tier build quality. MINI owners tell us it transforms the driving experience without drone in normal driving with the valve shut.

Fitting and support

Professional installation available at MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a tailored fitting quote or to discuss resonated vs non-resonated options, tailpipe choices and pairing with a sports cat or decat front section.

Good to know

• Backed by the manufacturer guarantee
• Pairs seamlessly with Cobra Sport sports cat or decat downpipe to create a full turbo-back system
• Supplied with all fixings and gaskets needed for installation

Popular search terms

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Watch and listen

MINI Cooper S F56 Valved Exhaust Sound, resonated catback with sports cat front pipe

VLOG, MINI Cooper S F56, valved exhaust, resonated catback with sports cat front pipe

Upgrade your MINI today
Add this switchable stainless catback to your basket for a deeper tone, improved flow and a premium tailpipe finish. For installation, package deals and advice on pairing with a sports cat or decat downpipe, contact info@mjmodifications.co.uk.