To turn fortunes around, Audi marketing chiefs decided a big V8 was needed - mainly to boost appeal among executive drivers. Trouble is, the regular A6's 4.2-litre unit is too big to fit under the Allroad's muscular front bodywork...
Enter Audi's 'smaller' 4.2-litre V8 - first fitted to the revised S4, it's some 52mm shorter. The firm has had to wind back the power because the five-ratio Tiptronic automatic box can't cope with the S4's 344bhp. But 300bhp and 380Nm of torque is a lot of muscle by any standards, and represents a hike of 30Nm over the 2.7T's V6 turbo.
On paper, the performance advantage is minimal, shaving 0.2 seconds off the 0-62mph time. However, the two engines' difference in character is clear. Where the turbo takes time to build speed, responding sluggishly to throttle inputs, the V8's broad torque band provides instant thrust. Acceleration isn't quite as forceful as the power output leads you to believe. But Audi's aluminum motor is one of the all-time great V8s; smooth, responsive and, thanks to some clever exhaust tuning, as musically accomplished as any BMW or Mercedes. It's also likely to form the basis of all future V8 projects, which is great news for Audi fans.
As with the A8, the Allroad fools you into thinking you're driving a much smaller, lighter car. The quattro four-wheel drive and taut suspension generate excellent wet-weather traction and high-speed stability. There is a touch less steering feel than before, but the extra grip from the 18-inch alloys more than makes up for it. The ride, too, is firm yet supple enough to take the sting out of bumpy tarmac.
At an expected £40,600, the newcomer carries a £7,520 premium over the 2.7T. But as well as that great engine and larger wheels, the Allroad 4.2 V8 benefits from xenon lights, a leather interior, matt finish body detailing and five new exterior colours. Maybe Audi's decision to keep the car in the UK was sounder than we suspected.
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