If Audi sells as many as 150 examples of its new S8 in the UK each year, it will have exceeded all expectations. In terms of sales figures, it's not therefore a particularly important car, but it is regarded as being a very special one - Audi people talk as if they regard it as being at the very top of their company's tree, as far as it could possibly be from the humblest A1. This, they imply, is the ultimate Audi.
It's substantially different from the S8 you could buy up to the first half of 2012. Most notably, the engine, which drives all four wheels through an eight-speed automatic gearbox, is an entirely new thing. Instead of the old V10 unit there's a four-litre twin-turbo V8 which produces an extra 69bhp (the maximum figure now being 513bhp) and makes this one of the fastest-accelerating Audis there is.
The new S8 can get from 0-62mph in just 4.2 seconds. Only 5.2-litre V10 R8s and some versions of the TT RS can beat that. No 4.2-litre V8 R8 can match it. The old S8 didn't even come close.
Despite that, this S8, while unlikely to be welcomed by Greenpeace, is nevertheless a lot more economical than its predecessor, with combined fuel consumption of 27.7mpg. Official CO2 emissions have dropped by 79g/km to 235g/km.
This is partly because turbocharged engines perform far better in the EU test than non-turbo ones do, and partly because Audi introduced its Cylinder On Demand technology which in certain circumstances imperceptibly converts this four-litre V8 into a two-litre V4.
When unleashed, the S8 is of course tremendously quick in a straight line, though you really have to give it the full beans before it starts to sound interesting. This is at heart a luxury saloon, and Audi's efforts to keep the racket down have been very effective. Whether or not you think this is a good thing depends on why you bought the car.
If, to change the subject slightly, you bought it because you thought it would be sporty, you will be sorely disappointed. Fast and sporty are not the same thing. The S8 grips tarmac the way tarmac grips the bit underneath it, and there was not a fraction of a second during this test when I thought, "Uh-oh, overdid it a bit there," even though I did give it the full beans a few times when there was no one else on board.
But it lumbers a bit through corners, and in particular it seems to take a long time to react to input from the steering wheel, as if the idea of changing direction hadn't occurred to it before and it's trying to work out why anyone would want to do that.
There's adapative air suspension, and you can fiddle with the settings, but there doesn't seem to be a way of improving the turn-in. Most of the changes appear to affect the ride quality - which, incidentally, and despite Audi's previous record in this area, is very good even on the test car's optional 21" wheels and ring-of-liquorice tyres.
As standard, S8s run on 20" wheels and higher-profile rubber. The upgrade costs £1565, which is something of a bargain compared with what else is available. For example, the test car also had electric sunblinds for the windows in the back half of the car, and those cost an extra £1020. This is a complete guess, but I'd be surprised if the profit on that is anything under £950.
There was also an upgrade to a Bang & Olufsen audio system for £5565. It was very good, too, but £5565? Really?
And, to top it all, "our" car had a special braking system centred on carbonfibre-reinforced ceramic brake discs. These are lighter than normal, which is always a good thing, fade resistance is described as "maximum", the operating life is said to be in the region of 180,000 miles, and they make the S8 stop like a son of a bitch. They also cost £8650. No, that's not a typo. £8650.
You really, really don't need the ceramic brakes. You just don't. If you're going fast enough to need them, you've bought the wrong car. But you can tell your friends about them, maybe demonstrate them once every couple of months, certainly boast that you were in a position to pay £8650 for them. Perhaps that in itself is worth £8650.
Something similar, I think, applies to the S8 as a whole. This car does nothing useful that a three-litre diesel A8 can't do too, but as an Audi person said to me people will buy an S8 largely for emotional reasons. He did not add, though I will, that those emotions may not always be very laudable, a desire to show off being one example.
If you are prepared to spend nearly nine grand on brakes that you don't need, it's not going to stop there. It is possible to buy an S8 for £79,360, but the car Audi gave us had so many extras in addition to the ones mentioned (four-zone climate control, front seat ventilation and massage, adaptive cruise control, a bird's-eye parking camera system, and on and on) that it would cost £107,075. A ridiculous sum, of course, but I doubt that the S8's small number of customers are particularly interested in value for money.
Being seen not to be interested in it is probably more important, so I would not be at all surprised to find that the majority of the hundred-and-whatever S8s leaving UK dealerships each year were specced-up to the point where they closely resembled this one.
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