Audi's RS6 has long been the go to choice if you needed a dementedly rapid big estate. The competition's become a lot hotter since the old V10 model was deleted. Can the latest improved V8 model cut it? Jonathan Crouch reports
Ten Second Review
The concept of accelerating from zero to 62mph in less than four seconds takes a bit of bending your head around, but that's the capability on offer from Audi's latest RS6. There's now the option of a 'performance' version with output boosted by 45PS to 605PS, but even if you go for the standard model, you're looking at a top speed of up to 189mph. That's coupled with potential for this leviathon to deliver up to 29.4mpg. Overkill doesn't come any more polished than this.
Does the luxury estate segment really need contenders offering the option of supercar performance? Audi thinks so. This improved third generation RS6 is the quickest model of its kind - as all its predecessors have been. Under the bonnet lies a 4.0-litre twin-turbo V8. Yes, the 560PS it delivers in standard form may have dropped slightly over what was on offer from the previous generation model's throbbing V10 unit, but this V8 is also lighter and more efficient than that V10, so still manages to create a car that is faster than ever, as well as being significantly cheaper to run. There's also now a 'performance' model that boost's its output to a thumping 605PS. In other words, there's no question of this RS6 having gone a bit soft in its middle age. If you doubt that, then just three or four seconds behind the wheel of this astonishing machine is all you need to underline its credentials. Let's check them out.
That 'world's fastest estate car' billing kind of clues you in to what to expect from the Audi RS6, but even knowing that fact ahead of driving it won't prepare you for quite how brutal and inexorable its power delivery is. Nothing can. Under the bonnet, the twin turbo 4.2-litre V8 doesn't yowl like the old V10 powerplant did, but that engine never felt particularly well suited to a big estate car. The reason? Torque - pulling power. Where the V10 could manage 650Nm of torque, this one's packing at least 700Nm and it's delivered all the way from just 1,750rpm, so you get the punch low in the rev range, meaning that the engine is never caught off the boil. As soon as you poke the accelerator, you've got its full measure. If you do need more, there's now a 'performance' version that boosts power from 560 to 605PS, cutting the rest to 62mph time from 3.9s to 3.7s and boosting torque by 50Nm to 750Nm. On the move at speed around especially tight twisty roads, this car never shrinks around you when you're really driving it hard - you're always aware that this is a sizeable hunk of machinery. But you're also always in awe of the fact that it feels so completely unflappable, with an almost complete absence of roll, understeer and pitch when accelerating or braking, thanks mainly to a couple of things - one mechanical, one electronic. The mechanical bit is covered by a sport differential that through the bends, actively distributes torque between the rear wheels. Electronics meanwhile, furnish you with a torque vectoring system that acts on all four wheels, lightly braking any about to lose traction during cornering.
Design and Build
The massive blistered wheel arches may not be as overt as they used to be, but it doesn't take long to figure out that this RS6 is no cooking A6 wagon. The most noticeable changes are the matte aluminium applications on the body, the matte black honeycomb radiator grille at the front of the car, the bumpers, the wings, the sill flares and the roof spoiler. At the rear of the car, the diffuser and the two large, elliptical exhaust tailpipes ensure that the back end looks as mean as the front. Go for the 'performance' version and your car will be marked out by accentuated bumpers with large air inlets up-front and a heavily profiled diffuser insert at the rear. There's also flared side sills and a gloss back honeycomb grille. Audi will sell you two optional exterior design packages - Matte Aluminium or Carbon - are also available to further customise the look. Inside it's as well finished as you'd expect from a range-topping Audi model with swathes of buttery honeycomb-quilted leather and slick controls that look and feel expensive. The driver's information system even gets a shift light which illuminates green segments as revs increase. The bar turns red and begins to blink when revs approach the red line. Space in the back is more than adequate, with up to 1,680-litres when the standard split rear seat folded.
Market and Model
It speaks volumes about the RS6's sheer substance that you can step out of this car and feel that spending the best part of £80,000 on one is more than fair value for money. Yes, that does mean that to get yourself into this 560PS super-estate, you'll be spending over £20,000 more than you would be for Audi's 420PS S6 Avant, a car less than a second slower from rest to 62mph and one hardly lacking much in desirability. But then this is a very special car and one that many will feel more than justifies what might, to the uninitiated, seem a pretty opportunistic mark-up. You do only get the Avant estate bodystyle this time round: the previous generation RS6 was offered as a saloon too, but the importers haven't bothered here because of the availability of the mechanically identical RS7 Sportback five-door hatchback model - which will cost you around £5,000 more. Like the RS7, this RS6 is, as we've been saying, offered in uprated 'performance' form and in this guise, the price rises to £86,000. As for rivals, well probably the closest would be the Mercedes-AMG E63 4MATIC, but seeing as the powers that be in Stuttgart won't import that all-wheel drive car to this country, we're left comparing the RS6 to the rear-wheel drive versions of Merc's E63 AMG wagon, of which there are two. Neither of them want for power compared to the RS6, but neither are as quick. For just over £75,000, you can get the 557PS E63 AMG estate or for a hefty £85,000-odd you can buy the S version of this car, packing 585PS. While the Mercedes probably edges the Audi in terms of tactility and drama, the Audi feels a more cohesive product.
Cost of Ownership
Efficiency is one area where the Audi RS6 is leagues better than any of its predecessors. The previous generation V10 model managed 20.1 and put out 310g/km of carbon dioxide, figures that just don't cut it these days. While you might question how relevant these measures are to buyers, they're good indicators of how advanced the technology underpinning the car is and manufacturers like to use them to keep score against each other. This latest RS6 manages 29.4mpg and emits just 223g/km, although a few grams less would have made a big difference to the VED taxation you'll pay. It gets to this point thanks to features like cylinder deactivation when cruising, lower kerb weight and its efficient eight-speed tiptronic transmission. Depreciation is a tough one to figure. Despite having an almost cult status, the fact remains that big, relatively thirsty petrol-powered estate cars tend to depreciate sharply. This Audi will require deep pockets to own, despite the increase in efficiency.
This may not be the most powerful estate car in the world but in every meaningful respect, it's the fastest, exactly as it was designed to be. Speed, it seems, is not directly relational to power and by shaving the weight, increasing the torque, improving aerodynamics and reducing friction in the engine, Audi has managed to do more with less. Quite how much more only really becomes apparent when you exercise the throttle pedal with intent. This thing is quite jaw-droppingly fast - certainly quick enough to make its key rival from Mercedes seem as if it's weighed anchor. It's not perfect of course. Steering remains the most obvious area for improvement, while some will feel the car's personality only really emerges when the optional sports exhaust is fitted. And, despite the weight savings, it's still large and heavy enough to lose a little to Audi's smaller RS 4 Avant model on tight and really twisty roads. It feels churlish to grumble though. The engineers at quattro GmbH have hit virtually all of their design objectives with this RS 6. It has a charisma of its own, an incredibly special interior and looks like a supercar's evil henchman from outside. Best of all, that devastating power never, ever loses its appeal. The result is an astonishing machine - and a monumental force to be reckoned with.