We rarely cover modified cars for Motoring Research, but this one’s a bit special. It’s a Ford Focus with more power than a Ferrari F40. Let that percolate for a moment. This four-cylinder hatchback musters 520 horsepower, versus 478 for the prancing horse. And while Mountune doesn’t quote a 0-62mph time for its M520 conversion, I’m certain it starts with a three.
That F40 alongside you at the lights? A near-as-dammit 3.9 seconds. How lucky do you feel?
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Mountune has been making Fords go faster since the late 1980s. The Brentwood company started with racing versions of the Sierra RS Cosworth and now offers kits for everything from the Fiesta 1.0 to the Mustang V8 – all of which can be fitted at Ford dealers.
Its best-seller is the M235 conversion, which gives the Fiesta ST an extra 35hp for £575. A near-200hp boost for the Focus RS is somewhat pricier…
Before I drive the M520, though, it’s time for a tour of Mountune’s inner sanctum. Engines for all Formula 3 racers are hand-built here, as were – until recently – those for the BTCC-winning Subaru Levorg. Other projects include modified Ford motors for the BAC Mono supercar.
Speaking of supercars, I also spy a Ford GT lurking in the workshop. Apparently, even 558hp isn’t sufficient for some.
Still, whether it’s the GT besting Ferrari at Le Mans or a Focus blitzing an F40 on the road, hot Fords often have ideas above their station. And the Mk3 Focus RS is no slouch to start with.
‘A five-star hot hatch that takes its place alongside the Fiesta ST, Escort Cosworth and other notable fast Fords in the pantheon of greats,’ gushed my review in 2016. Can Mountune really top that?
It’s willing to try. A massive ceramic ball bearing turbocharger, new valvetrain, spikier camshafts and heavy-duty fuel pump boost the 350hp Focus to 520hp. The kit costs £5,975, although Mountune says it requires ‘internal hardware modifications to ensure the RS achieves the desired performance safely and reliably’.
In practical terms, that means a full engine rebuild with forged innards. Reckon on £15,000 for the package and necessary upgrades.
Mountune m520 kit for the Focus RS comprises new engine internals, a ceramic ball bearing turbo, a high-flow fuel pump and a larger intercooler.
Other mods on this demo car include uprated front brakes, vented carbon fibre front wings and a carbon rear spoiler. pic.twitter.com/99Zt62YUF1
— Tim Pitt (@timpitt100) February 10, 2020
The Focus RS has never been for shrinking violets (remember the searing ‘Ultimate Green’ Mk2 version?), but this one is Q-car subtle. Vented carbon fibre wheelarches, a loftier rear spoiler and Mountune M52 alloys are the only clues to its added oomph.
Inside, the race-style Recaro buckets and dated dashboard are unchanged from the standard car. It’s a classic case of ‘speak softly and carry a big stick’.
The size of that stick becomes apparent when the rev counter passes 3,000rpm. The violence of acceleration pummels the air from my lungs and makes me giggle like a schoolboy. It feels preposterously, hilariously quick, a blunderbuss of boost that teleports the car from one corner to the next.
Like trying to watch a film on fast-forward, my brain struggles to keep up.
The tyres struggle a bit, too. The RS may be four-wheel drive, but most of its 516lb ft of torque is directed forwards, spinning the front wheels and corrupting the steering. Be brutal and it feels like a bucking bronco ride: a case of hang on and hope for the best.
Thankfully, a button on the steering wheel dials down the power for damp roads – and you soon learn how to drive smoothly, rather than smoking rubber like Ken Block.
No car in recent memory has made me ‘LOL’ like the M520. Even at nearly £40,000 – including a donor RS – you’ll struggle to get more bang for your buck.
Personally, I’d opt for one of Mountune’s milder conversions, which strike a better balance between power and poise. But if you want the ultimate hot hatch, look no further.
Price: From £37,000
Top speed: 175mph
MPG combined: 25.0
Ford Focus RS M520: in pictures