Review: Audi C6 RS6 (2008-10)

Overview

Released in October 2008, the Audi C6 RS6 was initially available as an Avant (wagon), with sedans following in February 2009. Manufactured in Neckarsulm, Germany, the Audi RS6 was powered by a 5.0-litre bit-turbo V10 petrol engine that was mated to a six-speed ZF 6HP26A automatic transmission and drove all four wheels via Audi’s quattro system.

5.0 TFSI V10: BUH engine

The C6 RS6 was powered by Audi’s BUH engine which had an aluminium-silicon alloy (AlSi17Cu4Mg) block, an aluminium alloy cylinder head, chain-driven double overhead camshafts, variable intake and exhaust camshaft timing over a range of 42 degrees, four valves per cylinder actuated by roller finger cam followers, dry sump lubrication, a compression ratio of 10.5:1, homogeneous direct injection (Audi’s ‘Fuel Stratified Injection’ or FSI) and two Bosch ME 9.1.2 control units in a master-slave configuration. Significantly, the BUH engine had two IHI RHF55 turbochargers (one per cylinder bank) that provided boost pressure of 1.6 bar (23.2 psi) and side-mounted intercoolers which condensed the intake air.

Dimensions and suspension

Compared to the Audi C5 RS6 , the C6 RS6 was 70 mm longer (at 4928 mm), 39 mm wider (1889 mm), 30 mm taller (1456 mm) and had an 88 mm longer wheelbase (2846 mm).

Like the Audi C6 S6 on which it was based, the RS6 had four-link front suspension with unequal length wishbones and self-tracking trapezoidal link rear suspension. The RS 6, however, was also fitted with Audi’s Dynamic Ride Control (‘DRC’) suspension system which used a pump to provide additional pressure in the diagonally linked dampers during cornering to minimise body roll and pitching. The system also had three modes – Sport, Dynamic and Comfort – which could be selected via the Multi Media Interface (MMI).

quattro

The Audi C6 RS6’s quattro system utilised a third-generation Torsen T-3 centre differential. In normal conditions, the front:rear torque split was 40:60, though up to 80 per cent of the engine’s torque could be directed to the front axle and 100 per cent to the rear axle. The front and rear axles were also fitted with open differentials with electronic differential locks which enabled cross-axle torque transfers by braking individual wheels.

Safety equipment

Standard safety equipment for the Audi C6 RS6 included dual front airbags, front and rear side airbags, full-length curtain airbags (i.e. for front and rear occupants), ABS, electronic brake force distribution, brake assist, electronic stability control, traction control, active front seat head restraints and front seatbelts with pretensioners and load limiters.

Brakes

The Audi C6 RS6 had cross-drilled, radially vented and floating iron brake discs, with 390 mm by 36 mm front discs with six-piston fixed Brembo calipers and 356 mm by 28 mm rear discs with single-piston calipers.

Features

Standard features for the Audi C6 RS6 included 20-inch alloy wheels with 275/35 tyres, a Multi Media Interface (MMI) with a thirteen speaker Bose stereo with six-stack CD player, satellite navigation system, DVD player and TV tuner, dual zone climate control air conditioning, Silk Nappa RS-embossed leather seats, heated front seats, directional xenon headlights, LED daytime running lights, front and rear fog lamps, steering-wheel mounted gearshift paddles, rain-sensing wipers, Bluetooth connectivity, voice recognition, leather-wrapped steering wheel, remote central locking with proximity key, a tilt and reach adjustable steering wheel, power sunroof, an alarm and immobiliser.

Related links

• Technical data: Audi C6 RS6 (October 2008)
• Brochure: Audi C6 RS6 Avant (October 2008)
• Wikipedia.org: Audi C6 RS6