Ford Focus ST (Mk4) Box Delete Race GPF-Back Performance Exhaust

These Ford Focus Mk4 ST performance exhausts are made in 3"/76.2mm pipework and fit from the Gasoline Particulate Filter section backwards (GPF-back) these exhausts replace the centre and rear sections.

All relevant fittings and gaskets are supplied.

This exhaust removes the standard rear box for the ultimate improvement in terms of exhaust tone and sound level whilst keeping the stock catalyst and GPF in place.

This exhaust system has been designed to be easily upgradable to a cat-back or full turbo-back exhaust in the future by purchasing additional sections. This exhaust has a choice of 4 tailpipe options including a 4.5" (114.5mm) carbon fibre tip.

GPF-Back (Box Delete) Test Results:

Sound - Engine at Idle: 65.9dB (+0.2dB) - Static 4,000rpm test: 92.0dB (+8.75dB)

Weight - 12.98kg (-2.75kg)

Cobra Sport Exhausts provide the performance exhaust solutions for the Mk4 Focus STs raced by the MB Motorsport accelerated by Blue Square and Motorbase Performance teams in the 2021 Kwik Fit British Touring Car Championship. This technical partnership allows us to test our products on track at the highest level of British Motorsport. The experience gained from the competitive track environment is fed back into all of our road going performance exhaust systems.

The Ford Focus ST has long been a favourite amongst hot hatch fans, especially in the UK, ever since the launch of the Mk1 ST170 back in 2002. The Mk2 ST moved Ford’s hot hatch game on even further in 2005 when they fitted it with a thundering 2.5 5-Cylinder engine. And in 2012, despite losing a cylinder and half a litre of capacity to its predecessor, the Mk3 still sold in the thousands.

Every generation of Focus ST has had seemingly limitless tuning potential thanks to their horsepower-hungry engines and playful handling characteristics. Cobra Sport have enjoyed enormous success in this field, with their performance exhausts for both the Mk2 and Mk3 Focus STs being amongst the best-selling systems in the market. Aiming to replicate this success, Cobra Sport are proud to announce their latest product range for the Ford Focus ST Mk4. Over the past few months, their Research and Development team have been hard at work developing an extensive range of performance exhaust systems that will cater to the needs of any fast Ford enthusiast.

Also available in the range is Cobra Sport's Cobra’s unique ‘Venom’ range. For those who want a further improve sound levels, the Venom exhaust removes the rear silencer to offer the biggest sound increase whilst keeping a sporty exhaust tone (+8.75db in GPF-Back Venom configuration).

Like all Cobra Sport exhausts, the Mk4 Focus ST systems are TIG-welded from high-quality T304 stainless steel and the mandrel-bent pipework is a full 3in (76.2mm) in diameter for maximum sound and tuning potential.

With over 25 years in the performance exhaust industry, each Cobra Sport exhaust system is designed, manufactured and tested in Sheffield, the heart of the UK steel industry. Cobra Sport utilise TIG-welding techniques to ensure a flawless finish and quality that you can rely on.

Ford Focus ST Mk4 Promotional Video (3" GPF-Back Exhaust)

Ford Focus ST Mk4 Sound Example (3" Venom GPF-Back Exhaust)

Ford Focus ST Mk4 VLOG (3" Venom GPF-Back Exhaust)

Cobra Sport Exhausts Ford promotional video.