This may look just like another Mitsubishi Evolution, but in one way at least what we’re dealing with here is something completely new. When Ford turned its Focus into the RS, inspired by a rally car, the 2 litre turbocharged engine was pushed to provide a heady 227bhp. Well, this new Evolution VIII also owes its inspiration to a rally car and similarly has a 2 litre turbocharged engine. Except this one has 405bhp.

That is an insane output for a 2 litre car. It’s more powerful than a twin-turbo Bentley Arnage R, which has an engine more than three times the size.

To put it in perspective, simple maths will tell you it is developing 202.5bhp per litre, a figure no other production car in the world has approached: a McLaren F1 produces 103bhp per litre, a Ferrari Enzo 108bhp. So the convolutedly titled Mitsubishi Evolution VIII MR FQ400 is an astounding proposition.

Only 100 will be built and all will be sold in the UK, at a price of £46,999. And this is not the work of back-street tuning cowboys who won’t guarantee the engine past the end of the street: it is a family saloon commissioned and sold by Mitsubishi, complete with three-year 36,000-mile warranty. Mitsubishi says it will honour the warranty even if the car has been used on trackdays, though this is at its discretion and will not apply to cars showing clear signs of cruel and unusual punishment.

But when you drive it, you wonder at first what all the fuss is about. At 2000rpm, when most turbo engines start to work hard, this one’s still asleep. At 3000rpm its eyes are opening and it requires 4000rpm before it’s showing some real interest. But get it to 5000rpm and you’d better know what you’re doing, and also have a great deal of road ahead of you. When this car is on song, straights vanish.

Mitsubishi claims the FQ400 will hit 60mph in 3.5sec and 100mph in 9.1sec, but because all the power required to deliver these numbers is concentrated between 5000rpm and the 7000rpm red line, in this narrow zone it feels faster still.

And herein lies its problem. Unless you’re driving it as fast as it will possibly go, it’s slower than a normal Evolution VIII. When you do ask for warp factor speed, the huge turbo takes a frustratingly long time to spool up and deliver the punch.

Which means that, in the real world, it’s nothing like as fast as it seems. If you’re waiting to overtake and a gap appears, you have first to change down, then nail the throttle and count to three before the bang in the back arrives. By which time many theoretically slower cars would be gone.

What, however, is not in doubt is the ability of the rest of the car to handle this power. The brakes, which are to a bespoke specification, are so powerful I half expected them to trigger the airbags, while the chassis, with its active centre differential and electronic yaw control systems, proves more than capable of coping with the performance without throwing you off the road.

But you can have the same chassis in an FQ320, which still offers 326bhp yet costs precisely £17,000 less, and for an extra £1,652 the same brakes, too.

It may not be what Mitsubishi intended, but what the FQ400 does best is illustrate the great value of cars such as the standard Evo VIII and the FQ320. The basic Evo VIII costs just £23,999, which means you can almost get two for the price of the FQ400. And the FQ320 offers a blend of real-world practicality, searing speed and driver involvement unmatched by any other car costing less than 30 grand. The FQ400 is clearly quicker, but is it more rewarding to drive? Not in this book and not at that price.

And the name? I have it direct from Mitsubishi that 400 refers roughly to its power output and FQ to the words that come out your mouth the first time you sample it. And, yes, the Q is “quick”.

With that, at least, I fully concur.