Even by Californian stakes, the styling is no shrinking violet and quite a change over the classy A6 Avant. Only the roof, front doors and tailgate are carried over to the RS6, with every part sculpted to look more aggressive, most notably the flared wheel arches housing the wider tracks and bigger alloys, new bonnet, rear spoiler, and front and rear bumpers. It looks more like a GT3 car than an estate with some of the addenda – and, to these eyes, brilliant.
The looks leave you in no doubt about what kind of engine powers the RS6: a big, powerful V8. Whereas the RS4 has switched from a V8 to a V6, a V8 is retained in the RS6 – and significantly upgraded with a larger turbocharger and increased boost pressure. The twin-turbo 4.0-litre unit produces a colossal 591bhp and 590lb ft and is hooked up to an eight-speed Tiptronic automatic gearbox and a proper Torsen differential-based permanent four-wheel drive. There’s also a torque-vectoring diff at the rear.
The engine itself is now a mild-hybrid unit, mated to a 48V system to boost energy recuperation (see separate story, right). It works for efficiency reasons only rather than performance, not that the RS6 is wanting in the performance stakes: 0-62mph takes a claimed 3.6sec, traction off the line aided by a new launch control system, should you feel the need.
Chassis-wise, height-adjustable adaptive air suspension is standard, the car sitting 20mm lower than the A6 Avant and a further 10mm lower above 74mph. Steel coils with Dynamic Ride Control (DRC), which is an interconnected hydraulic damping system, is included on the range-topping Vorsprung version. (There are three RS6 trims in the UK: the standard £92,750 car with 21in alloys, the £100,650 Carbon Black with 22s and the £109,250 Vorsprung also with 22s.) The active all-wheel steering system from the RS7 features here, as does the option of ceramic brakes over the standard steel set-up that also raises the top speed to 190mph if the brakes are specced on the Vorsprung trim.
There are fewer changes inside than outside, and less added aggression. The seats (very comfortable and supportive) are new, as is the steering wheel, which has larger shift paddles, but the capaciousness of the standard A6 Avant remains. Fido should be kept happy by the 565-litre boot, rising to 1680 litres with the 40/20/40 split rear seats folded flat.
Two customisable driving modes (RS1 and RS2) allow you to pick out the best bits of the standard Comfort, Auto, Dynamic and Efficiency modes that tweak all major dynamic components, including the engine and transmission management, suspension and steering. In the RS2 mode, you can also now turn off the electronic chassis control systems for the first time in an Audi RS model.