BMW M3 (F80) 3" Secondary De-Cat Bypass Performance Exhaust

Unlock serious flow and a harder soundtrack for your F80 M3 with these 76.2 mm stainless secondary catalyst delete mid-pipes. Designed as a direct add-on to the Cobra Sport valved cat-back system, this straight-through centre section removes the factory second converters to reduce back pressure, sharpen throttle response and let the twin-turbo straight-six breathe and sound as it should.

• 3 inch 76.2 mm T304 stainless steel pipework for maximum gas velocity and durability
• Replaces the secondary catalysts only - a true catless mid-pipe upgrade
• Optimised for the 3.0 litre twin-turbo inline-six for improved flow and an angrier tone
• Pairs perfectly with the Cobra Sport valved cat-back for a balanced, aggressive exhaust note
• All required clamps and hardware supplied, aside from the two OEM gaskets noted below

Fitment

• Exclusively fits the Cobra Sport valved cat-back, reference BM103
• Pre-PPF vehicles only
• Requires 2 x BMW gasket, part number 18307851168 - not included

Real-world results

Matched with the corresponding valved rear system, Cobra Sport development testing recorded notable power and torque improvements thanks to the free-flowing 3 inch layout and advanced gas flow design. Combine these mid-pipes with BM103 to maximise performance potential and achieve a deeper, more aggressive soundtrack under load while retaining civility when cruising.

Why buy from us

We have fitted this upgrade for customers in our workshop and the feedback is consistently positive - stronger mid-range pull, faster turbo spool and a much more purposeful tone without the dull, muted stock character. The transformation is exactly what enthusiasts want from an M-car exhaust mod.

Important notes

• Sold for motorsport and off-road use only worldwide
• Removing the secondary catalysts can trigger an EML - an ECU remap is recommended to resolve this and to stabilise any performance gains
• Pre-PPF models only

Professional fitting

Want it installed correctly first time? Book fitting with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a tailored quote.

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