THE term express delivery is about to take on a whole new meaning with the arrival of Audi's third generation RS 6 Avant estate model.

How about carrying up to 1,680-litres of luggage to 62mph in a mere 3.9 seconds - and on to a top speed of 189mph? Eyeball-flattening stuff.

Then there's the fuel economy. Audi says that it's possible to return an average 28.8 miles per gallon, though some considerate footwork would no doubt be required to match that figure.

When the new supercar hits the streets next summer it will cost £77,000 and be powered by a 4.0-litre V8 bi-turbo petrol engine which is actually quicker than the 5.0-litre V10 engine used in the previous model.

At the same time the smaller displacement, combined with cylinder-on-demand technology, makes the claimed fuel consumption a 40 per cent improvement on before.

Peak output of 560PS is reached between 5,700 and 6,700 rpm, with a constant 700Nm of torque available between 1,750 and 5,500 rpm.

And switchable flaps in the exhaust system will make the classic V8 soundtrack even fuller at the touch of a button, and a sports exhaust system will be available as an option for even greater amplification.

In its standard form the RS 6 Avant's top speed will be electronically limited to 155mph, but it's possible to increase it to 174mph with the optional Dynamic package, and to reach 189mph with Dynamic plus.

The 4.0-litre powerplant is paired with an eight-speed tiptronic transmission featuring shortened shift times and offering both Sport and Manual modes in addition to the standard Drive setting. And there's also Audi's quattro permanent all-wheel drive system.

The car will also be the first Audi RS model to feature adaptive air suspension, which lowers the body by 20mms and adds controlled damping which takes into account road conditions and driving style.

As an alternative, sports suspension plus with Dynamic Ride Control will also be available along with dynamic steering.

High-gloss, 20-inch, forged wheels in a seven twin-spoke design will be standard along with more powerful brakes.

RS-specific design touches include a matt black honeycomb radiator grille, bumpers, wings, sill flares and roof spoiler, while inside the instruments feature black faces, white dials and red needles and there's a flat-bottomed steering wheel.

RS honeycomb-quilted Valcona leather sports seats with pronounced side bolsters, integrated head restraints and RS 6 logos will be included and among the standard equipment are xenon plus headlights, LED rear lights, tyre pressure monitoring, illuminated entry sills and driver's info system.

Also on board will be the parking system plus with visual and acoustic prompts, cruise control, four-zone automatic air-con, MMI navigation plus with MMI touch, BOSE sound system, DAB radio and Audi Music Interface.