What do we have here?
A Ford Focus RS that's been given a once over by those clever chaps at Mountune, liberating an extra 25bhp and 30lb ft of thrust from the already-thrusty 2.3-litre EcoBoost engine. For the non-mathematicians among you that takes the total to 370bhp and 376lb ft, and drops the 0-62mph time from 4.7 seconds to a Porsche 911-worrying 4.5 seconds. Top speed remains at 165mph.
There goes the warranty…
A-ha! That's where you're wrong. The FPM375 Power Upgrade, to give it its proper name, is fully compatible with the base vehicle warranty, so you can still claim for mechanical failure. It will set you back a mere £899, too, and can be fitted at any Mountune-appointed Ford dealer in around 90 minutes.
So what do I get for my money? Big wing, ceramic brakes, semi slicks?
What for £900? Steady on. No, the only changes are to the engine, which gets a new high-flow induction kit, a reflashed ECU, a sound suppression chamber (to stop unwanted whistling as air passes over the compressor housing) and an upgraded recirculation valve (essentially a blow-off valve integrated into the turbo). You also get a Mountune badge, but we suggest leaving it off and confusing standard RS drivers at the lights.
How noticeable is the extra power?
Very. I have the benefit of running a standard Focus RS currently so my right foot and backside are sensitised to 345bhp. This, without question, is a more manic and eager experience. And we're not just talking about a more vivid rush at the top end, the performance is swollen everywhere, so throttle pick up is a fraction cleaner and it charges harder from anything above 2,500rpm.
We'd never accuse the standard RS of being slow, but at 1599kg it is heavy, so the acceleration gap between it and the 296bhp Golf R isn't anywhere near as wide as you'd expect. This upgrade creates clean air between the two, pulling the RS alongside the real titans in the hot-hatch game - the Mercedes-AMG A45 and Audi RS3.
You don't need to be thrashing it to feel the benefit, either. That extra torque means it surges forward even on part throttle openings, so smooth, swift cross country progress is ridiculously easy. Motorway overtakes in sixth are that bit more clinincal, too.
Sound any different?
Subtly, yes. Mountune will sell you a lighter, louder stainless-steel ‘Axle-Back' exhaust for another £1,050, but even with the regular pipes you can hear the turbo working harder. As boost builds so does the noise - more of a distant rush than a traditional whistle - followed by a satisfying ‘pssst' from the blow-off valve when you lift off past 4,000rpm. Nothing intrusive, just a gentle reminder there's some extra chemical to kinetic energy conversion going on in front of you.
Does it still like corners?
Lives for them. All the touch points - the well weighted steering, progressive brakes, chunky gearshift - are all identical and as sublime as ever, the only differences are when you toggle through the modes. Sport - my default setting for the sharper throttle response and pops on the over run, but not the cement dampers you get in Race - feels much the same, but Drift is a little livelier.
Whereas with the standard engine it helps to provoke the RS into a slide with a well-timed bung before getting hard on the throttle, here you can unstick the rears far easier - as I discovered… unintentionally. Not that there's anything to be scared of, it's still one of the world's easiest cars to go sideways in - a drift car for beginners if you like.
So would you go for it?
Yep, all day, every day. A no-brainer for me. For the price of an optional wheel nut on a Bentley, you can unlock yet more of the RS' potential, but keep all the bits you liked about it before. Much like Game of Thrones, or white Twix - the FPM375 is something I wasn't aware I needed, but now I've had a taste it's difficult to imagine life without it.
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