The Mazda Furai could be the most convincing concept car ever to grace a motor show stand. Concept cars are usually designed as eye candy, a device to draw crowds to venues like this week’s British International Motor Show, and grab headlines in car magazines in the hope of creating a buzz around a manufacturer’s brand. Yet the vast majority of them are delicate flowers, capable of walking speed at best.

Not the Furai. For once, the scarcely believable performance figures you’ll see here aren’t theoretical; they’re the real deal. This is a concept car that really will accelerate to 60mph in 3.2sec and power on to 172mph: having felt the full fury of the Furai (Japanese for “sound of the wind” and pronounced foo-rye), I can vouch for the head-spinning numbers.

To give the Furai the performance to match its sensational swirling bodywork, Mazda turned the concept-car process on its head. Instead of beginning with a visual concept and then working out how to make it driveable, Mazda used a fully formed race-car chassis as the Furai’s starting point. So underneath that wildly sculpted body, you’ll find the Courage C65 chassis with which Mazda’s racing arm campaigned during the 2005 and 2006 American Le Mans Series (ALMS).

The Furai also uses the race car’s motor, a three-rotor rotary engine that develops 460bhp, which is a huge output for a car that weighs just short of a ton. It can run on either petrol or ethanol, and its power is delivered to the rear wheels through an Xtrac six-speed sequential gearbox with Formula One-style shift paddles.

While the Furai’s body looks typically concept car, with deeply scalloped vents everywhere you look, Mazda insists that the styling is all about aerodynamic function. The vents on top of the front wings, for example, relieve the high air pressure that builds up above the front wheels at speed. The recessed side vents, which look terrific, feed cooling air to the rear brakes as well as the oil and transmission coolers. Even the dramatically shaped headlight surrounds are designed to counteract lift at the front end.

One of my favourite touches is a device that Mazda calls, amusingly, the “turbo tongue”. That’s the slightly raised tongue-shaped air intake on top of the Furai’s roof – it looks like a bit of design whimsy but it’s entirely functional, enabling the engine to ingest “cleaner”, less turbulent air. In fact, it works so well that Mazda has applied for a joint patent with Swift Engineering, the outfit that worked with Mazda on the Furai’s aerodynamic package.

But could the experience possibly live up to the Furai’s visual promise? We unleashed it at Kemble airfield, near Cirencester, where Mazda had laid out a circuit that would enable me to experience the Furai’s entire performance envelope. As Mazda’s chief test driver warmed the Furai up over a couple of laps, I watched and felt shivers running down my spine. And, oh Lord, the noise when he stabbed the start button. A guttural, uneven bark (race engines hate idling) that makes you instinctively jump back, and then the ragged buzzing bass as he speared away in first gear.

The volume and power of the noise rattled my internal organs, like standing too close to those 10ft speakers at Glastonbury. And then, as it runs up through the gears, the engine note smooths out to a mournful howl. Add more speed and the Furai wails like an F1 car.

Helmet on, I’m ready. Mazda’s Stig-like test driver rolls up, kills the engine and gestures for me to climb on board; it’s time to experience the ultimate ride, shotgun-style. The Furai’s cabin is a tight fit for two, but as he’s using the steering-wheel-mounted gearshift paddles, that’s not a problem. The heat, though, is worse than a Swedish sauna in midsummer.

Ignition. The Furai slams into first gear and, with a big woof of throttle, the car points down the straight and into the first corner. The acceleration is unbelievable, my head snapping back against the seat with every savage gearshift. And there’s the corner coming at us – intellectually, I know that the car will go round, but my instinct is shouting: “No way!” It’s an effort to keep my head upright as the Furai scythes through, the driver banging through the gears as we hit a long straight, 90, 110, 120, 150mph, and then into another impossible corner.

The amount of lateral grip here is unlike anything you would ever experience in a road car, even a Lamborghini. Another long, high-speed straight, and, just to demonstrate the fact, Mazda’s test driver jinks the steering from right to left, yet the Furai feels rock solid and stable. It feels, in the end, just like what it is – a race car.

Back at base, I emerge from the car drenched in sweat and a little light-headed. The Furai has made the point in grand style.

Sadly, delicious though the idea of a roadgoing, production Furai is, that’s not going to happen. Mazda is using this concept to remind people that it has a genuine motor sport heritage, and to reinforce the company’s “zoom zoom” philosophy, be that through the styling or the unique rotary engine. For me, though, this is the first time in my career that a concept car has actually overdelivered on its visual promise. Now that’s what I call a novel concept. See it for yourself now at ExCel.

Mazda Furai

ENGINE 1962cc, three-rotor rotary

POWER 460bhp @ 8800rpm

TORQUE 278lb ft @ 8800rpm

TRANSMISSION Six-speed manual

FUEL 2.3mpg (at race speed)

CO2 n/a

PERFORMANCE 0-60mph: 3.2sec

TOP SPEED 172mph

PRICE n/a

VERDICT It will put the wind up you