Review: Audi RS6

I am a Luddite.

I have clutched with feverish intensity to the good ole days of atmospheric engines that used cubes to create performance rather than embrace the emerging era dominated by snails and superchargers.

Mine was a purist's affection based primarily on engine response and aural delights. But now, having driven the new Audi RS6 Avant, I must acknowledge that my cubic fixation is no longer justified.

Forced induction now not only holds significant advantages in specific outputs (power and torque per-litre), low-rpm driving and real-world fuel economy, but turbocharged V8s like the RS6's 412kW monster also deliver superb soundtracks and the engine response high-performance drivetrains deserve.

Neither is the equal of a free-breathing V8 (6.2-litre V8 in the Merc SLS and 4.0-litre V8 in the BMW M3 are two that come to mind), but it's close enough that holding to my previous beliefs is no longer defensible.

The RS6 wasn't the first twin-turbo V8 to win my grudging respect; that was the Mercedes-Benz E63 AMG with the optional 410kW power kit.

But the RS6 proves the Merc was no fluke. Twin-turbocharged V8s rule the high-performance executive saloon world, and with good reason.

The RS6's new 4.2-litre twin-turbo V8 replaces the old model's twin-turbocharged 5.0-litre V10. Despite losing 14kW peak power (now it has 'just' 412kW) it is a significant real-world advance.

For starters the smaller engine has 50Nm more torque and yet is 30 percent more fuel-efficient (9.8 v 14), partly thanks to cylinder deactivation. The engine is also 50kg lighter, which is a fair chunk to remove directly over the front axle, and notably benefits front-end reactions and steering feel.

This more modern engine also tears seven-tenths of a second from the 0-100km/h time, now 3.9 seconds, catapulting the RS6 ahead of its main rivals because it doesn't suffer the tractive challenges of rear-drive.

On wet roads it is possible to notice the rear tyres slip when flooring it from a standstill, but the RS6's quattro all-wheel drive quickly brings the front axle on-tap and the scenery soon blurs.

Overall the RS6 is 100kg lighter than its impressively quick predecessor, yet is marginally longer and wider, and rides on a 70mm longer wheelbase. For the first time on an RS6, air suspension is standard.

The RS6 also gets the S8's 8-speed torque convertor auto to go with its new engine, its shift times improved to impede the wagon's brutal acceleration as little as possible.

This is a seriously quick performance car with few drawbacks.

It is as much fun in the twisties as it is on the straights, and has all those wonderful aural accompaniments — gravelly engine note, trailing throttle backfires, up-change overrun — that elevate the experience beyond the mere thrilling to truly exhilarating.

And the best bit: The 2013 RS6 will carry a $230k price tag when it arrives in Australia in November, $47k less than the previous model's 2008 launch price.

That's line ball with the M5 which it beats for acceleration and economy.

And don't forget the practical benefits of the wagon body style - and the sleeper cred it brings.