Mini GP3 (Mk3) JCW (F56) 3" Cat Back Performance Exhaust

Unleash the soundtrack and flow your GP deserves

Looking for a serious sound and performance upgrade for your John Cooper Works GP? This Cobra Sport stainless system transforms the GP hot hatch with a deeper tone, sharper throttle feel and stunning tailpipe options. Crafted in the UK from premium T304 stainless with smooth, mandrel-bent 76.2 mm pipework and immaculate TIG welds, it delivers that aggressive, motorsport-inspired note while maintaining day-to-day usability.

Why owners choose this system

• Free-flow 76.2 mm bore for improved gas velocity, reduced back pressure and enhanced turbo response.
• Made in Sheffield, UK from T304 stainless steel with precision TIG welding for long-term durability.
• Choice of sound levels:
  • Silenced centre section for a refined, sporty tone on the road.
  • Straight-through centre section for a louder, more aggressive soundtrack with amplified crackles, pops and bangs.
• From the catalyst rearwards - replaces centre and rear sections for a true rear system upgrade.
• Tailpipe choices to suit your style: 3.5 inch or 4 inch outlets, with ceramic coated black or carbon fibre tips available.
• All required clamps, hangers and gaskets are included for a straightforward installation.

Sound and driveability

Months of development went into creating a soundtrack that complements the playful character of the GP. With the non-resonated setup in Sport mode, independent testing recorded 86.4 dB at 4,000 rpm on track conditions. Expect a deeper idle, pronounced growl under load and a crisp overrun character that puts a grin on your face every drive.

Build quality you can trust

Cobra Sport has over 25 years of UK manufacturing experience. Every system is designed, fabricated and tested in-house using mandrel bends, high grade fixtures and meticulous TIG-welding for a flawless finish that stands up to daily use and track days alike.

Upgrade path ready

Planning further tuning later on? This rear system pairs perfectly with Cobra Sport sports catalyst or de-cat front sections to create a full turbo-back upgrade. Ideal for owners seeking freer flow and headroom for ECU calibration.

PPF, GPF, OPF note

Cars equipped with a petrol particulate filter may require basic ECU tuning at the time of installation to prevent an engine management light. Intended for motorsport and off-road use where applicable.

Our experience and customer feedback

We have fitted and tested this system on customer GPs and the feedback has been excellent. Owners love the richer tone, the premium finish and the transformation in character without unwanted drone when choosing the silenced option.

Professional fitting

Want it installed correctly the first time? Book fitting with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

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