Mountune has released two new upgrades for the Ford Focus RS that are claimed to elevate performance to levels not seen before.
The first of the two performance packs, the m450 upgrade that costs £2950 ($A5300), sees the current Focus RS' turbocharger binned for a fresh Mountune configured BorgWarner EFR-6758.
Boosting power further, the kit also adds a high-flow sports cat and down pipe.
With the new blower and freer breathing exhaust in place, the result is a boost in power from the standard car's 257kW/440Nm to a far punchier 330kW and 580Nm.
They're espectable figures, but fork out £5975 ($A10,700) and you get the full fat m520 kit.
This introduces a larger Mountune-fettled BorgWarner EFR-7163 turbocharger, an uprated fuel pump, camshaft and valvetrain plus a new ECU calibration that bumps power and torque to an incredible 383kW and 700Nm.
Mountune has not released any performance figures for its latest creations but it's thought even the least powerful upgrade could shave as much as a second off the car's claimed 0-100km/h time, making a sprint time of around 3.5 seconds likely.
In the UK, Mountune has been producing performance parts for more than 35 years and remains the only tuner officially approved by Ford of Great Britain.
Some of the performance parts offered do not affect the standard car-maker's warranty.
Despite the public backing, Ford Australia has yet to announce plans to officially import the go-faster parts for the Focus RS Down Under.