Currently reading: Ford Fiesta ST gains 232bhp Mountune tuning kit
New upgrade package includes power and torque boost for latest version of hot hatch

Ford tuning specialist Mountune has developed its most powerful tuning upgrade yet for the Fiesta ST, raising the output of the hot hatch to 232bhp.

The firm’s new m235 kit, which costs £575 including VAT, offers an extra 10bhp from the previous M225 upgrade and gives the 1.5-litre turbocharged three-cylinder engine an extra 35bhp from unmodified versions. It also boosts the Fiesta’s peak torque to 258lb ft, compared with the official 214lb ft of the standard version.

Alec Pell-Johnson, Mountune’s performance chief, claimed the kit “delivers both significant performance and driver enjoyment”.

As well as upgrading the output of the Fiesta ST engine, the modifications include developments to boost usability and performance, while ensuring the car retains the feel of an official manufacturer model. No-limit shift optimisation is included as part of the kit calibration, which combines with the firm’s established enhanced exhaust overrun function.

M235 trk 40

The m235 kit includes an extended durability cycle that monitors cylinder pressures when additional ignition is used, providing a "significant and usable" increase in power and torque throughout the rev range. The upgrade has been subjected to what Mountune calls a “rigorous testing and development process”.

Customers will be able to use Mountune’s Smartflash app to install and control the calibration, allowing them to make changes to the performance of their vehicle as required. The m235 upgrade includes three calibrations, including a Performance setting with more aggressive launch control and enhances exhaust noise, and an Anti-Theft setting that fully immobilises the car.


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James Attwood

James Attwood, digital editor
Title: Acting magazine editor

James is Autocar's acting magazine editor. Having served in that role since June 2023, he is in charge of the day-to-day running of the world's oldest car magazine, and regularly interviews some of the biggest names in the industry to secure news and features, such as his world exclusive look into production of Volkswagen currywurst. Really.

Before first joining Autocar in 2017, James spent more than a decade in motorsport journalist, working on Autosport,, F1 Racing and Motorsport News, covering everything from club rallying to top-level international events. He also spent 18 months running Move Electric, Haymarket's e-mobility title, where he developed knowledge of the e-bike and e-scooter markets. 

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Peter Cavellini 19 February 2020

Baseball Cap ready!

 Seriously, this'll frighten a few premium sports cars.