Audi S6 Avant 5.2 FSI: Spotted

Supercar engine yet indistinguishable from a 2.0 TDI - stealthy speed never looked so good

To offset a weekend of racing Caterhams and bagging his first ever goes in Ferraris and old 911s we sent Matt on an Audi A6 facelift launch yesterday. Amid the rep spec 2.0 TDI Ultras (doubtless on 21-inch S Line wheels and coming to a rear bumper near you soon, according to our Audi stereotypes bingo card) he should hopefully have also sampled the revised S6. "They still make an S6?" you may be asking. Indeed they do.

Think Ronin but for the school run instead

History shows that while RS models can blow hot and cold the downplayed S versions are often the discerning hot Audi of choice. And never did the lines of aesthetic conservatism and mechanical loopiness intersect so spectacularly as they did with the C6 generation S6. Yep, the V10 'Lambo' engined one.

In the initial press release on the car's launch at Detroit in 2006 Audi did acknowledge the link with the Gallardo's powerplant, the S6 actually predating the R8 V10 and therefore officially the first V10 powered Audi sold. It had a "5.2-litre V10 FSI petrol engine developed using Lamborghini Gallardo's 5.0-litre unit as its technical basis" according to that first introduction. But in truth the engine's lineage can be traced back to the Audi 4.2-litre V8s used in the RS4 and R8 (in 32-valve form) and in the S4 and S8 (40-valve). It shares these engines' bore and stroke, the S6's V10 more closely related to the R8's V10 and unit in the later direct-injected Gallardo LP560-4. It may lack the blunderbuss power of the turbocharged RS6 but that direct supercar link arguably makes it more exotic, especially combined with the boggo looks.

Smart interior? Check...

Before we get lost in engine designations it's basically a hell of a motor to find in a dark blue Audi A6 Avant, this one benefitting from a Milltek exhaust and small bit of tweaking to bump power from the standard 435hp to more like 450hp. Compared with modern Audi engines it's a peaky unit too, topline horsepower at 6,800rpm and its 398lb ft of torque demanding 3,000rpm before it comes knocking. That and the two-tonne starting weight probably blunt the edge of that headline-grabbing engine and make it feel slower than 0-62 in 5.3 seconds suggests but it should at least sound good trying.

And an Audi wouldn't be an Audi without yer official 'class leading interior' and the S6 branded, leather clad Recaros and discreet carbon trim certainly tick those boxes. Being an Avant it obviously has a giant boot too and were it not for the quad exhausts and special wheels nobody would give it a second glance. Even then few people would clock what it is, given the aforementioned and omnipresent 2.0 TDI S Lines handily have 99 per cent of the look, with about 1 per cent of the appeal. Rendering this supercar engined family estate all but invisible, and therefore even cooler.

Absolute anonymity, ludicrous speed - we like!

It's at this point your correspondent has to admit to absolutely zero first-hand experience of the V10 S6, beyond idle speculation that it sounds like a rather appealingly low-key way to go very fast indeed. As a four-wheel drive all-weather weapon for the approaching wintergeddon it appeals rather more than the Q7s pushier brand fans now favour (house!), leaving the S6 to those who look back on a day when Audis were the German brand of choice for those who didn't feel the need to shout about it.

A Proper Audi then; aesthetically understated, mechanically esoteric and relatively cheap to buy, if quite possibly completely ruinous to run. Respect due to anyone willing to do so though.

And if anyone can tell us what they're like to drive now's your chance...

AUDI S6 V10 TSI (C6)
Engine: 5,204cc V10
Transmission: 6-speed auto
Power (hp): 435@6,800rpm
Torque (lb ft): 398@3,000rpm
MPG: 21mpg (And that's the official NEDC combined figure...)
CO2: 319g/km
First registered: 2006
Recorded mileage: 95,000
Price new: £56,600 (before options)
Yours for: £12,750