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Ford tuning specialist Mountune is well known for upgrading the Blue Oval’s hot hatches, but the company has evidently decided its existing option for the Fiesta ST just wasn’t potent enough. As a result, the firm has added a new package that squeezes a handful more horses from the little hatchback.

Dubbed the m235 upgrade, the new package is a step above the existing m225 option, which eked 225 horsepower from the 1.5-liter turbocharged petrol engine. With the £575 ($745) upgrade, however, that is increased to 232 hp, while peak torque rises to 258 lb-ft (350 Nm).

Despite the increase in power, though, the upgrade is based on the m225 package, which uses the Mountune induction kit. That includes a tig-welded aluminum airbox with a secondary cold air feed point, a high-flow air filter, and a porous secondary air-feed hose. Not only does that allow the company to increase the car’s power, but it also increases induction noise to add aural appeal.

Both packages supplement that with a phone-controlled tuning system that changes the way the engine behaves. In the case of the m235, that means the power delivery has been modified to “transform” the driving experience. There’s an enhanced exhaust sound, as well as a no-lift shift setting that makes upshifts smoother without the need for the driver to lift off the throttle.

The system comes with three settings, including an anti-theft setting that allows the driver to immobilize the car so it cannot be driven away. By the same token, there’s also a setting that returns the car to its standard state of tune. The third and final setting, however, is the full-bore 232-hp setting, which includes modifications to the sport and track modes to make the launch control system more aggressive.

And although these upgrades incorporate significant changes to the car’s performance and hardware, Mountune says the packs are designed to ensure “the vehicle remains safe and reliable”. The company also says it aims to provide an “OEM-plus” feel to the car, giving the impression the vehicle left the factory with the upgrade attached.

“The m235 power upgrade shows how much fun there is to be had from the Mk8 Fiesta ST,” said Alec Pell-Johnson, director of Mountune Performance. “We’ve worked hard to improve on the already impressive m225 kit and with the introduction of no-lift shift optimization and an enhanced exhaust overrun, our latest kit provides drivers with a product that delivers both significant performance and driver enjoyment.”

The Mountune m235 kit costs £575,($745) although customers who already have the m225 upgrade can switch to the m235 for £99 ($128).

Gallery: Ford Fiesta ST Mountune M235

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  • Power & torque are further enhanced in the award-winning Mk8 Ford Fiesta ST
  • m235 upgrade increases power by 10PS and torque by 10Nm over previous m225 upgrade
  • Innovative SMARTflash app allows easy DIY install and calibration for owners which also features DTC reading
  • mTune SMARTflash m235 package is priced at £575 inc. VAT when upgrading from a stock calibration
  • For more information, please visit

19 February 2020, Brentwood. Fans of the blue oval can now get even more out of the Mk8 Fiesta ST with mountune’s most recent performance upgrade. With each kit unveiled by mountune, the award-winning car comes more and more to life. Significant developments have been made in usability and performance to ensure the car retains an OEM+ feel. The m235 package is no exception as the Fiesta ST further develops on the significant increases to both power and torque that were delivered as part of the previous m225 upgrade.

The m235 upgrade has undergone a rigorous testing and development process to once again deliver a package that puts the driver firmly in control.  An extended durability cycle monitoring cylinder pressures with the use of additional ignition, now provides a significant and useable increase across the majority of the rev-range versus the previous m225 kit, maximising the potential of the 1.5- litre 3-cylinder EcoBoost engine.

Increasing both power and torque by 10 PS and 10Nm respectively, the ST now boasts a peak power output of 235 PS and 350Nm of torque. Benefits of the latest calibration are not restricted to solely improved performance - new to the m235 upgrade, the no-lift shift optimisation included within the calibration, makes smooth and precise lift-less gear changes easy, combining with our popular enhanced exhaust overrun to create an optimum driving experience.

“The m235 power upgrade shows how much fun there is to be had from the Mk8 Fiesta ST,” explains Alec Pell-Johnson, Director of mountune performance. “We’ve worked hard to improve on the already impressive m225 kit and with the introduction of no-lift shift optimisation and an enhanced exhaust overrun, our latest kit provides drivers with a product that delivers both significant performance and driver enjoyment.”

Once again customers are able to take advantage of mountune’s innovative mTune SMARTflash app, allowing them to install the latest calibration from the comfort of their driveway. Using nothing else but the mTune SMARTflash app on their smartphone and the supplied Bluetooth OBD interface, Fiesta ST owners can completely change their vehicle. The intuitive SMARTflash system has been designed to make selection between different calibrations simple and fast, giving users the freedom to change the vehicle to suit their needs. The new app also enables mountune customers to effortlessly update their vehicle with the latest calibrations directly from mountune and includes a convenient VIN and calibration ID reader.

Three distinct calibrations are included with the m235 upgrade, providing users with a range of practical options. The m235 Performance calibration delivers the previously mentioned power and torque increases alongside a more aggressive launch control strategy and enhanced audible exhaust output in Sport/Track modes. The other two calibrations are Stock Performance, which returns the vehicle to its standard configuration and Anti-Theft, which fully immobilises the vehicle.

Proud ST owners wishing to install the m235 upgrade from stock settings should purchase the m235 mTune SMARTflash kit, complete with Bluetooth OBD interface.

Customers who wish to incorporate the optimised no-lift shift and exhaust overrun functionality to upgrade from the m225 package, can upgrade their calibration via SMARTflash and apply it via their smartphone or tablet.

The complete m235 package includes:

  • SMARTflash EVI Bluetooth OBD adapter
  • mTune SMARTflash app, available for both Android and Apple
  • No-lift shift optimisation and enhanced exhaust overrun
  • 3 useful calibrations: Performance, Stock and Anti-Theft
  • High-flow induction kit
  • mountune badge
  • mountune zip-up shell case
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