Here we have yet another fast Audi, but what is it that makes this rapid limousine so special?
Next shout 'READY, STEADY, GO', plant your foot to the floor and begin counting the seconds: 'one, two, three, three-and-a-bit', and boom - that’s 62mph, right there.
To be scientific about it, the exact time is 3.8sec, which ladies and gents, makes it the fastest-accelerating limo you can buy.
We once described the standard S8’s potency in the realms of ‘lunacy’, for it’s no sloth - not with 513bhp, which is available for those who feel the Plus's 597bhp is a tad too wild for them. But somehow that wasn’t enough for the chaps at Ingolstadt (or Audi's Neckarsulm plant, where the S8 is built), and I think you have to admire delusion on such an epic scale.
Don’t think they’ve thrown in another piffling 10bhp as a marketing ploy to lever a few extra sovereigns out of perennially late plutocrats; the Plus adds a hefty 84bhp, with peak torque boosted to 516lb ft, or 553lb ft if you count the overboost function.
It’s a feat achieved by re-mapping the engine to increase boost pressure and stretching the rev limiter by 200rpm. To cope with the extra stress there’s been some beefing-up of the internals, including stronger head gaskets and modified exhaust valves.
Fundamentally the drivetrain remains the same. The engine’s mighty output is distributed to all four wheels through an eight-speed Tiptronic automatic gearbox. From there, and under normal circumstances, a central differential sends 40 percent of the drive to the front axle and 60 percent to the rear - where it’s divided once more by an electronic limited-slip diff. But, if needs be, up to 100 percent of the drive can go to the rear.
As the standard S8 has been known to cook its brakes when driven hard, we'd opt for the Dynamic Pack. It includes fade-resisting 19in carbon-ceramic brake discs and swaps the 155mph limiter for one that pegs things at 189mph instead.
The result is brutal acceleration accompanied by a gloriously deep baritone rumble from the quad tailpipes – which for S8 Plus spotters, are painted black instead of the standard car's chrome.
One Audi engineer told me this car should crack 200mph with no restrictor, and they’d only limited it because of the tyres - or perhaps to spare the blushes of the Bentley Flying Spur? Judging by the phenomenal rate at which the S8 Plus keeps pulling, even when it’s already at mammoth speeds on a de-restricted autobahn, I feel no reason to doubt the claim.
In these situations Dynamic mode works best. It stiffens the suspension and helps keep the big Audi planted even as you motor past trundling HGVs. It also weights up the Dynamic Steering, which otherwise feels a bit insubstantial, albeit quick.
The test route didn’t take in many twisty roads, but preliminary analysis indicates that for its size, the S8 is pretty wieldy. Traction is epic and it manages to resist rolling much on its uprated air springs, even as you pile on more cornering speeds and lateral g.
However, all this agility isn’t at the expense of the S8’s other role as a cosseting chariot for the well-heeled. Yes, it has smoother-riding peers, but switch to the softer Comfort mode and it floats along without much fuss, even on the standard 21in rims.
Whether it’s because of the trick noise-cancelling software or layers of old-school sound deadening, the road and wind noise never startle, even at very startling three-figure speeds.
If you’ve had a particularly stressful day, you can ensconce yourself in the big, quilted leather seats with contrasting red piping and stitching. You may choose to unwind further with the massage feature, or maybe fire-up the Bang & Olufsen stereo, both of which are on the options list. Whatever your pleasure, you can bask in the glory of one of the most solidly built interiors that money can buy.
As for the standard equipment front the S8 is certainly well-equipped as you would expect on a £80,000 plus car. The 'entry-level' S8 gets all the equipment found on the SE Executive trimmed A8s and adds 20in alloy wheels, Audi Sport tweaked air suspension, electronic differential and steering, along with LED headlights and 360 degree camera on the outside, while inside there is a Bose sound system fitted, a CD/DVD player, acoustic glazing, a Valcona leather upholstery and 22-way electrically adjustable front seats.
Upgrade to the S8 Plus comes with a black exterior trim, electric rear sunblinds and Alacantra and Nappa leather touches throughout the cabin. As is the way with luxury limousines expect the options list to be hefty and very pricey, although if you are shopping at this end of the spectrum that shouldn't really be a surprise or a concern.
So to the million dollar question - should you buy one of these super limos? Well, you may think it's pointless, bonkers and unnecessary, and to be honest you’re probably right. Perhaps a more fitting question is: ‘do I want one?’ Well, I do, very much as it happens. The S8 Plus made me smile. A lot. Something its nearest rivals failed to do - namely the Mercedes-AMG S 63 and the Bentley Flying Spur.