The Ford Focus ST was sadly discontinued in the US market back in 2018 along with the Fiesta ST, leaving a hot hatch-shaped hole in Ford's American car lineup. In the US, the Ford Edge ST is now the only high-performance ST model available.

To remind us what we're missing out on, UK tuner Mountune has been extracting more power from the Focus ST with its performance kits. Last year, Mountune's m330 package increased the output of the Focus ST's 2.3-liter EcoBoost engine to 325 hp and 380 lb-ft of torque, up from 276 hp and 310 lb-ft in the standard model. This already made the Focus ST more powerful than the Volkswagen Golf R and Honda Civic Type R, but this hasn't stopped Mountune from taking it to the next level and unlocking its true performance potential.

Building on last year's m330 package, Mountune's latest upgrade dubbed the m365 increases the hot hatchback's peak power to 365 hp and 416 lb-ft, an increase of 89 hp and 106 lb-ft over the standard Focus ST. This also makes it more powerful than the last-generation Focus RS, which was rated at 350 hp and 350 lb-ft of torque. Since Ford is no longer planning to revive the Focus RS for a new generation, does this make Mountune's Focus ST the next best thing? Not quite.

Whereas the Focus RS comes with AWD as standard, Mountune's Focus ST still sends power exclusively to the front wheels. Mountune hasn't released any performance specifications, but the modified hatchback should be faster than the standard model, which will sprint from 0-60 mph in less than six seconds.

The power boost is achieved using Mountune's Bluetooth OBD dongle and SMARTflash smartphone app, as well as a high-flow panel air filter and a three-inch high-flow exhaust with sports catalyst.

"We are delighted to launch our latest upgrade kit for the much-loved mk4 Focus ST. Ford has done a great job with the stock ST and what we have done with this m365 upgrade kit is to fully optimize the calibration with our newly engineered low-back pressure exhaust hardware - this means maximum performance is available throughout the rev-range and it's now a seriously fast car, which is also great fun to drive, too," said David Mountain, Managing Director at Mountune.

In the UK, Mountune's m365 kit starts at £689 ($956.80), but an upgrade kit is also available if you already own the m330 kit for £99 ($137.48).