BMW M135i (F40) Cat Back Performance Exhaust

Cobra Sport
Stock to order In stock

Requires mandatory ECU reflash when fitted to PPF models. Fitment is for motorsport and off road use only. 

Cobra Sport performance exhausts enhance the sound, looks and quality of your vehicle giving you the ultimate driving experience. Our sports exhausts range is fully guaranteed to give you assurance of our quality.

This BMW M135i performance exhaust is made in 3in/76.2mm pipework and fits from the front catalyst section backwards (Cat-back) replacing the PPF, centre and rear sections.

The resonated exhaust includes the centre silencer and has a subtle but sporty tone. This exhaust however, is also available as a non-resonated version which is a louder option as it excludes the centre silencer and therefore, has a sportier exhaust note.

IMPORTANT: this exhaust removes the PPF filter and will require engine tuning at time of fitment to cancel the EML light.

Fitment is for motorsport and off road use only as this system removes the PPF filter. 

Please Note:

The 'Valved' exhaust retains the use of exhaust valves. When switching drive modes (e.g. Eco to Sport mode) your exhaust tone will continue to swop from quieter to louder tones as before.

The 'Non-Valved' exhaust removes the use of exhaust valves. When switching drive modes (e.g. Eco to Sport mode) your exhaust tone will not change from quieter to louder as before. Using a Non-Valved exhaust will not harm the running of your vehicle, you will simply not have exhaust sound options, however the Cobra Sport exhaust has been designed with this in mind.

Fitted images show the non-valved resonated version.

All relevant fittings and gaskets are supplied.

Press Release

The third generation of BMW’s 1 Series was launched in 2019, with the chassis name F40. For the performance range topping F40, BMW revived the ‘M135i’ moniker, which had not made an appearance on the back of a Baby BMW since its predecessor, the F20 M135i.

Sporting BMW’s B48 2 litre, 4-cylinder engine with Twin Power Turbo technology, the B48 produces 306hp and a thumping 332lb ft of torque. These punchy figures fire the M135i from 0-62MPH in just 4.8 seconds and on to an electronically limited top speed of 155 MPH. The M135i is shipped from the factory with a muted exhaust sound leading to a very disappointing driving experience.

Along with increased performance, Cobra Sport were keen to put the emotion back into the drive with an improved aural and emotional experience. Cobra Sport opted for 3”/76.2mm stainless steel pipework which is larger than most on the market for the biggest upgrade in terms of performance, flow rate and sound levels. The free-flowing Cobra Sport exhaust setup completely transforms the vehicle and will open up the future tuning possibilities of the BMW M135i (F40).

During the design stages, Cobra Sport made sure that all of the configurations are interchangeable so that customers can add to their system over the coming years. We imagine most will start with the PPF back configuration which can be fitted without the need for any engine tuning as it keeps the stock catalyst and PPF in place (MOT compliant). Adding a PPF delete section would create the cat back setup and customers going down the tuning route can add a high flow sports catalyst or de-cat front pipe to create a full turbo back setup.

For those who want further improve sound levels, Cobra Sport offers their unique rear silencer delete range. This exhaust setup removes the rear silencer to offer the biggest sound increase whilst keeping a sporty exhaust tone (+13.1dB in PPF back rear silencer delete configuration).

The Cobra Sport team were able to reduce the weight of the exhaust system by an impressive 49% over the OEM system with the PPF back rear silencer delete system weighing in at only 9.02kg compared to the original 17.8kg.

Cobra Sport have improved the styling of the BMW M135i, creating a noticeably enhanced and balanced look to the rear of the M135i with a choice of dual 4” (101.6mm) and 4.5” (114.3mm) slash cut highly polished stainless-steel tailpipes. For those looking to take the style upgrade a stage further, upgraded carbon fibre tailpipes are available.

Like all Cobra Sport exhausts, the M135i F40 exhausts are TIG-welded from high-quality T304 stainless steel and the mandrel pipework is a full 3” (76.2mm) in diameter for maximum sound and tuning potential.


Example of the Cobra Sport BMW M135i Exhaust (GPF Back with Box Delete)

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