Audi RS6 Avant is world's wildest wagon

Audi has announced full details and specs of its ballistic new RS6 Avant, which will be by far the fastest station wagon offered in Australia when it launches here in late 2013, serving up a 0-100km/h split of 3.9 seconds and top whack of 305km/h.

Due to make its world debut at the Detroit motor show in January, the car is actually speed-limited to 250km/h in standard configuration, but this rises to 280km/h with the optional Dynamic package and 305km/h with the Dynamic plus package – the latter putting it in an exclusive club of 300km/h-plus supercars.

Meantime, its sub-four-second 0-100km/h time makes it 0.6 seconds quicker than both its predecessor and Porsche’s new 911 Carrera S (4.5 seconds), and a whole second quicker than Audi’s latest S6 Avant (4.9 seconds).

More importantly, Audi’s wildest wagon is also four-tenths quicker than its nearest rival, the turbocharged 5.5-litre V8-powered Mercedes-Benz E63 AMG Estate, which slams out 410kW/800Nm with an optional performance package and can hit 100km/h in 4.3 seconds.

Propelled by Audi’s new twin-turbo 4.0-litre petrol V8 – a higher-output version of the engine seen in the latest Bentley Continental GT and the 309kW/550Nm S6 Avant - the stonking wagon thrashes out 412kW at 5700-6700rpm and a beefy 700Nm of torque between just 1750rpm and 5000rpm.

That might be 12kW less than the naturally aspirated 5.2-litre V10 that powered the previous RS6 Avant, but the new RS6 engine delivers peak power 550rpm earlier and offer an extra 50Nm of maximum torque than its predecessor’s Lamborghini-sourced V10.

Audi says the engine’s tractability is maximised by the two large twin-scroll turbochargers, which are mounted together with the intercooler in the inside V of the cylinder banks (as per the latest BMW M5).

Audi claims the RS-specific engine management and induction system makes for fast response and a “sporty, full-throated sound”, with switchable flaps in the exhaust system making the sound even fuller, if desired.

However, in case it’s still too subdued for your tastes, you can tick the box for an optional sport exhaust system that’s even more vocal.

The company says the 4.0-litre TFSI engine exemplifies its downsizing strategy in the high-performance category, with an average consumption figure of 9.8L/100km – hardly gas-guzzler material.

Contributing to its frugality is a start-stop system and cylinder on demand (COD), which shuts down the intake and exhaust valves of cylinders two, three, five and eight at low throttle loads. All eight cylinders kick in within a few hundredths of a second if you tromp on the gas.

Performance and economy also benefits from the fact the new RS6 is about 100kg lighter than its predecessor at around 1875kg, thanks to the extensive use of alloy throughout the car.

Drive to all four wheels is relayed via an eight-speed tiptronic automatic transmission with what Audi claims are shortened shift times. The transmission can be left to its own devices or stirred via steering wheel-mounted shift paddles.

At the heart of the Torsen torque-sensing permanent all-wheel-drive quattro system with torque vectoring is a self-locking centre differential, and the RS6 is the first RS model to come standard with bespoke air suspension, which lowers ride height by 20mm. Also on offer are conventional steel springs and three-way adjustable shock absorbers.

The standard stoppers are six-piston steel discs (390mm diameter), but if the occasional track day is on the menu, you may want to specify the optional carbon-ceramic discs (420mm diameter).

The RS6 rides on 20-inch, forged wheels in a seven twin-spoke design, but an even chunkier stance can be had via optional 21-inch cast wheels that are available in three versions: high-gloss silver, polished black and polished titanium-look.

Other visual clues that distinguish the RS6 from lesser Avants – including the S6 - include a more aggressive front fascia, sill flares, a large roof spoiler, elliptical exhaust pipes and a rear diffuser.

Two styling packages will be available, at least in Europe: matte aluminium and carbon, with the latter adding even more muscular front and rear-end treatments.

Inside, there are RS sport seats trimmed in black Alcantara and leather (Valcona leather in either black or Moon Silver is optional), plus the usual array of RS-specific accoutrements.

The standard rear seats are a pair of sportily moulded buckets, but a three-person bench seat is available as an option.

The luggage compartment holds up to 1680 litres, so the RS6 is about as practical as any 300km/h-plus car can be.

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