The tuner Mountune has new kits for the Ford Focus RS that takes the hatchback from hot to steaming. The m450 pack increases the output to 444 horsepower (331 kilowatts or 450 metric horsepower) and 428 pound-feet (580 Newton-meters) of torque. The even spicier m520 pushes the figure to 513 hp (383 kW or 520 metric hp) and 516 lb-ft (700 Nm). The heart of both of these upgrades involves replacing the stock turbo with a BorgWarner EFR Series unit.

Gallery: Ford Focus RS Mountune m450 and m520 kits

For the m450, Mountune fits a turbo with a low-inertia turbine wheel and dual-row ceramic ball bearings. The kit also includes a revised turbo adaptor, downpipe, and high-flow catalytic converter. The tuner charges £2,950 ($3,591 at current exchange rates) for the upgrade.

The m520 is more expensive at £5,974.99 ($7,272) but comes with additional go-fast parts. For example, the engine gets new camshafts, and an upgraded fuel pump ensures gas feeds the powerplant. Revised ECU tuning optimizes the upgrades, too.

In stock form, the Focus RS has 350 hp (261 kW) and 350 lb-ft (475 Nm) of torque, so these upgrades offer significant improvements in the hot hatch's output. However, the RS is no longer available in America and seems unlikely to return anytime soon. The next-gen model in Europe reportedly retains a 2.3-liter turbocharged four-cylinder but with the addition of hybrid assistance for a total output above 400 hp (298 kW). Look for it to arrive outside of the U.S. in a couple of years.

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m450 & m520 MRX upgrades are perfect for customers already running the m400R or m400X packages
OE turbocharger replaced with Borg Warner EFR Series large frame unit as part of m450 and m520 MRX kit
New m520 MRX available to owners seeking to extract maximum performance
m450 and m520 are priced from £2,950.00 inc VAT & £5,974.99 inc VAT respectively
m450 & m520 preview video:
19 August 2019, Brentwood. Petrolheads can now get even more out of their Ford Focus RS with the introduction of two new exciting power upgrade packages from mountune - the m450 and m520. Unveiled to the public for the first time at Ford Fair earlier this month, each kit brings the RS to life, reaching a level of performance not seen before. Both the m450 and m520 upgrade kits replace the OE turbocharger with a specifically engineered BorgWarner EFR Series turbocharger to dramatically increase peak power and torque outputs.

The m450 package sees the OE turbocharger replaced with the mountune configured BorgWarner EFR-6758 turbocharger delivering an increase of 50PS, allowing the driver to get the most out of their 2.3-litre EcoBoost without breaking the bank. Utilising the unique Low Inertia Gamma-Ti Turbine Wheel, the m450 upgrade increases the power output to 450PS and 580 Nm of torque. Furthermore, the inclusion of Dual Row Ceramic Ball Bearings ensures that drivers can push their RS to the limits, achieving quicker acceleration and higher speeds as a result of lower friction and increased response rates from the new turbo.

Also included as part of m450 are the mountune Ni-resist Cast Turbo Adapter, V-band high flow sports cat and downpipe, Turbocharger Gasket Set, mountune 5-Ply Compressor Outlet/ Inlet Silicone Elbow and Stainless-Steel Hose Clamp Set - all expertly fitted by one of mountune’s experienced engineers at their Brentwood HQ, and alternatively will also soon be available on the mountune online store.

The m520 package takes the RS to the next level, above and beyond the capabilities of m450. Whilst some of the m450 package remains for the m520, the turbocharger has been upgraded again, to a mountune configured BorgWarner EFR-7163 Turbocharger. In addition to this, the m520 upgrade package also includes an XtremeDi uprated Di fuel pump and revised/uprated camshafts and valve train, which together with the turbocharger and a revised ECU calibration, take the power of the RS to a staggering 520ps and 700 Nm of torque.

“We have worked hard to develop upgrades that build on the success of the m400X and m400R kits,” explains Alec Pell-Johnson, Director of mountune Performance. “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.”

With the m450 and m520 upgrades including all hardware, fittings, and hoses needed for the installation, both kits are an easy addition to those already running the m400R or m400X. Enhancing the capabilities of the Ford Focus RS has never been easier.

Both the m450 and m520 MRX upgrades are available to purchase now starting from £2,950.00 Inc. VAT & £5,974.99 Inc. VAT respectively.

Please be aware that both kits require engine internal hardware modifications to ensure the RS achieves the desired performance safely and reliably.

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