The V8 powerplant is identical to that used in the new S4, and a more compact variant of the unit found in the A6 and S6. With 300bhp on tap, the Allroad has turned into a capable high-performance load-lugger.
The short first gear gives stunning throttle response off the line, and, if you keep your foot down, 60mph arrives in only 7.2 seconds. Amazingly, that makes the new soft-roader only half-a-second slower over the 0-60mph dash than the super-sporty S6, and the car has a top speed of 149mph.
Despite this, the Allroad also has genuine mud-plugging abilities, with four-level air-suspension and permanent four-wheel drive allowing surprisingly adventurous off-road excursions.
Flagship V8 versions are only available with Audi's five-speed Tiptronic automatic gearbox, which means the 4.2 does without the low-ratio mode that is the preserve of the manual. But unless they need to do any serious towing, most buyers will find that the steering wheel-mounted gear selectors are a much more useful feature.
Predictably, drivers will pay the price for all that power at the pumps - a combined fuel consumption figure of 20.8mpg won't win any prizes, but the Audi is still more frugal than its heavier, taller rivals. Carbon dioxide emissions of 331g/km place the Allroad 4.2 in the highest company car tax bracket, although the Audi is still cleaner than the majority of its opponents.
As with every eight-cylinder Audi, there's a fine V8 growl to keep you aware of the performance potential. And unlike the S6, the Allroad has a cosseting, smooth ride, which easily absorbs bumps and potholes and makes for a fine motorway cruiser.
The compliant suspension also gives the car a much more controllable feel over rough tarmac, and it has less tendency to follow undulations in the road than the S6. However, there is not as much feel through the steering.
Priced at £40,510, the well equip- ped newcomer undercuts the S6 Avant by £8,145, but adds £6,700 to the cost of a 2.7 T Allroad. While it's a lot of money, you get an estate, off-roader and performance car all rolled into one.
That's not good news for Porsche, because the firm is marketing its more expensive, slower and less versatile £44,530 Cayenne S on many of the same strengths. The Audi might not have the same badge heritage, but it will certainly give potential Cayenne buyers something to think about.
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