Seconded from the Audi stand at the Los Angeles motor show, where it made its world premiere, the new Audi concept looks magnificent in the midday sun as it sits in the driveway of a Beverly Hills hotel – ready for us to climb aboard and take the wheel.
Distinguished by its wide single-frame grille, angular headlamps, taut surfacing, low and prominent shoulder line, subtle crease lines, traditional wheel arch flares and finely honed tail-lamp detailing, it is truly eye-catching, with a greater hint of athleticism to its lines that current Audi models. Yet despite the fresh design lineage, it is also unmistakably an Audi at first glance.
At 5100mm in length, 1950mm in width and 1390mm in height, the Prologue is 40mm shorter, the same width and 70mm lower than the current A8. Audi's research and development director, Ulrich Hackenberg, suggests that those dimensions will be retained for the production version of the A9.
The custom cast 22-inch wheels, which fill the sizeable wheelhouses with precious little room to spare, are supported by suitably wide tracks, giving the Prologue a terrifically confident stance.
Before I’m able to drive the Prologue, though, I’m asked to pull on a disposable polyethylene overall. Too new, too expensive and frankly too rare, the car’s minders are taking no chances, suggesting the blue dye in my jeans might discolour the leather upholstery.
The long driver’s door automatically opens at the wave of my hand over a sensor within the upper trailing edge, and inside you find a highly innovative cabin that provides seating for four on individual seats. The cabin makes extensive use of contemporary touch-and-swipe functions on a series of high-resolution display units that replace the fascia to give it a wonderfully clean and orderly look.
The cabin is beautifully finished in a liberal covering of leather, brushed aluminium and fine wood veneer. After a short cockpit drill, I slide into a broad but supportive driver’s seat that includes every-which-way electric adjustment behind a neatly proportioned four-spoke, multi-function steering wheel that also adjusts electrically for rake and reach. The driving position is spot on.
The immaculate dashboard incorporates an instrument panel featuring a full-width OLED panel with three separate displays – something that not only provides it with high-tech appeal but also serves to accentuate its width. Audi’s idea is to enable simple digital interaction between the driver and front-seat passenger via swipe commands.
A fourth display includes a fascinating bending OLED panel, one of just 10 in existence right now, according to Audi. It's mounted at the base of the centre console. At the touch of a button, its trailing edge motors upwards to provide the driver with easy access to infotainment, climate control and a host of other functions – all just a hand’s length ahead of a stubby T-shaped gear selector.
There is a strong hint of mechanical potency the moment I hit the milled aluminium starter button on the centre console; the engine fires instantly with a deep blast of exhaust before settling down with an alluring rumble at idle.
With my right foot set firmly on the brake, the electrically operated gear selector requires nothing more than a light backwards nudge with my index finger to send the eight-speed automatic into drive – as indicated within the mesmerizing three-dimensional instrument display. Then, we’re off.
Sitting up front underneath the new concept car’s relatively low-set bonnet is Audi’s familiar twin-turbocharged 4.0-litre V8 petrol engine. In a hint of what’s to come for the next-generation S8 and its more sporting S9 sibling, the 90-degree unit has been tuned to deliver 597bhp and a nominal 516lb ft of torque – or an even more prodigious 553lb ft in overboost mode during short bursts of full-throttle action.
The heady reserves are channelled through a traditional eight-speed torque converter automatic gearbox and Audi’s torque-sensing four-wheel drive system with a torque vectoring function at the rear.
As well as featuring a cylinder-on-demand arrangement that shuts off four of the eight cylinders on light throttle loads for added fuel efficiency, the engine showcased in the Prologue also uses a 48-volt electrical system – a development that Audi insiders indicate will be adopted on the next A8 and the A9 as part of a new generation of fuel saving initiatives.
The new 48-volt electrical system employs a belt starter generator, which provides the advanced V8 with mild hybrid capability and an energy recovery output of up to 12kW under braking.
So configured, Audi suggests that the production version of the Prologue will return nearly 33.0mpg on the combined fuel economy cycle to give it average CO2 emissions of under 200g/km.
Initial impressions? Well, the big Audi has all the typical hallmarks of a concept car. A lack of ride height means approaching a driveway at anything more than walking pace would risk ripping off the expensive-looking polished carbonfibre splitter attached to the leading edge of the front bumper. So I gingerly manoeuvre out of the hotel, being careful to angle the nose of the Prologue out on to the road to avoid any cringeworthy scrapes.
An exploratory prod on the accelerator reveals that engine response is a little tardy at low revs, due to excess engine bay heat that, Audi engineers say, has caused the electronic throttle mapping to intermittently retard the ignition.
Once I’ve negotiated my way through an initial dead spot in the delivery, though, the turbochargers spool up and the sharp-looking concept smoothly builds up speed.
The Prologue rides on a heavily modified platform from the current A8, although such is the extent of the changes that it is virtually a new structure – one that provides solid clues to the underpinnings set to be used by the next-generation A8 and the A9.
As well as reducing the wheelbase by 50mm to 2940mm, Audi has also provided its latest concept car with a thoroughly new five-link rear multi-link suspension sporting adaptive air springs capable of varying the ride height.
In a more significant move, it also receives a four-wheel steering system that allows the rear wheels to turn by up to five degrees for improved manoeuvrability around town and greater agility on the open road.
For the new Audi’s unveiling, the advanced suspension has been lowered quite significantly in the name of style, robbing the Prologue of any meaningful wheel travel. And those custom 22-inch wheels are shod with purposeful 285/30 Pirelli P Zero tyres offering little in the way of additional compliancy.
Predictably, there is some sharp vertical pitching as we turn right at the traffic lights and set off down Rodeo Drive to the stares of onlookers.
But, wow, there’s encouraging feel and accurate action to the steering. Like many other aspects of the mechanical package used by the Prologue, the electro-mechanical system is taken directly from the S8. It is allied to the new rear steer mechanism that helps to provide the big coupé with an outstanding turning circle of just 8.5 metres – less than that of the significantly smaller A3, or so says Audi.
The Prologue may be a concept, but there is real substance to its low-speed manoeuvrability. Even at limited speeds, it possesses the makings of a very appealing production car. It steers in a direct manner, changes direction eagerly and corners in a flat and unperturbed way.
Once I’ve got the Prologue percolating along at a constant speed, the ride also settles and the car's true character begins to shine through.
At 40mph there is sufficient compliancy to call it comfortable, although admittedly the smooth- surfaced roads of our route weren’t exactly taxing the suspension to any great degree.
Encouraged to up the pace, I lean on the throttle, at which point the sleekly styled two-door suddenly feels a lot less like a delicate concept and more of a brutish performance car.
With 3000rpm wound on the engine, the initial hesitancy in the throttle response disappears and the advanced V8 begins to propel the Prologue along with the sort of authority you would expect of a car set to rival the Mercedes-Benz S-class coupé.
Audi suggests the production version of the Prologue will hit the scales at around 1980kg and possess a 0-62mph time of just 3.7sec, which seems entirely believable when you consider the huge shove displayed on a wide open throttle.
The shift action of the gearbox is pretty sweet, too. The ZF-sourced unit engages higher gears smoothly and is quick to downshift when you come off the throttle. The brakes, somewhat over-servoed in a way all Audis used to be, are quite sensitive at the top of the pedal’s travel. But they’re manageable enough at the limited speeds I’m pulling.
Each brief increase in acceleration between the traffic lights is accompanied by a glorious blare of exhaust, and it is not long before our police escort switches on a siren and flashing blue lights to clear traffic, allowing us to cruise uninterrupted through the heart of Beverly Hills in true celebrity style.
That said, there are limits to how much I’m prepared to push. For one, the Prologue has been hand-built and is far from being a true road-going prototype.
It is also the only example in existence, and I don’t want to be the one to tell Hackenberg that his priceless concept car, completed just five days prior to our drive, has gained some unexpected styling modifications.
Still, if Audi is to be believed, we won’t have to wait too long before the production version reaches showrooms. Given the trouble it has gone to, it would seem odd to build up expectations of a new range-topping model in the way it has if it wasn't going to grant it a definitive production green light sometime soon.
But while the pillarless two-door coupé body style of the concept is an intriguing proposition, there are hints that the production version of the A9 will receive a more practical five-door liftback layout similar to that used by the A7.
In a segment of the market known for convention, it would be a daring move. But I’m sure it would win Audi many admirers.
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