It's been about six months since Mountune unveiled its 400hp m400X upgrade for the Focus RS, which means it's high time the Brentwood firm gave us even more power to sink our teeth into. And wouldn't you look, here it comes now, in the form of not one but two new packages, dubbed the m450 and m520.
These, unsurprisingly, put out 450hp and 520hp respectively, but whereas the previous increases in output were available with nothing cleverer than a re-map, these new developments require a turbo upgrade to reach such attention-grabbing numbers.
In the case of the m540 that means a specially-engineered BorgWarner EFR-6758, sporting a Low Inertia Gamma-Ti Turbine Wheel and Dual Row Ceramic Ball Bearings to be exact, which offers maximum responsiveness while "dramatically increasing peak power and torque outputs." It's joined beneath the bonnet by Mountune's Ni-resist Cast Turbo Adapter, Turbocharger Gasket Set, 5-Ply Compressor Outlet/Inlet Silicone Elbow, Stainless-Steel Hose Clamp Set and V-band high-flow sports cat and downpipe, all of which are included in the kit.
The m520 package, meanwhile, offers a more powerful turbo still, with a Mountune-configured BorgWarner EFR-7163 taking the 6758's place. In addition to this, an XtremeDi fuel pump, plus an uprated valve train and camshafts and a revised ECU calibration take the RS' output to 520hp and 516lb ft of torque. Which is quite a lot.
Mountune states that both kits are an easy addition to cars already running its m400R or m400X set-ups, with upgrades including all hardware, fittings, and hoses needed for installation. The two options are available to purchase now, with the m450 starting from £2,950.00 including VAT and the m520 beginning at £5,974.99.
Speaking of its latest releases, Mountune Performance Director, Alec Pell-Johnson, said: "We have worked hard to develop upgrades that build on the success of the m400X and m400R kits. With the very latest BorgWarner turbocharger platform, both upgrades deliver exceptional levels of power and torque, turning the RS into something quite remarkable. After the positive initial feedback we received from the official unveiling of the kits at Ford Fair, we can't wait to start fitting them to our customers' cars."