Driven: Audi launches RS5 Cabrio in Oz

AUDI has released the fastest four-seater convertible in its history in the guise of the RS5 Cabriolet.

Priced from $175,900 plus on-road costs, it joins the coupe version that has been on sale in Australia for some time, and which now benefits from a $5500 price cut.

That’s already on top of a $13,900 snip when the Series II facelift arrived in August last year.

Sitting above the S5 Cabriolet launched in late 2009, the RS5 version pushes out the performance envelope with significant increases in outputs, suspension and brakes, to help justify its positioning on top of the ageing B8-series A5 tree.

It also introduces the Audi Connect in-car multimedia, internet, satellite navigation and audio system option (for $800), which allows for real-time data to be downloaded into the car.

Like all Audi drop-tops, the newcomer gets an electronically operated fabric roof in this case it falls in 15 seconds, erects again in 17s, and is operational on the move up to 50km/h.

Additionally, it features an extra layer of ‘acoustic’ dampening to quieten noise-intrusion levels down to “almost coupe” standards, according to a company spokesman.

Audi trainspotters can ID an RS5 Cabrio by its unique honeycomb grille, larger front air intakes, standard high-intensity discharge Xenon headlights with daytime driving lights, extended wheel arches and body sills, bespoke boot spoiler, fatter twin exhaust pipes (with sound flaps for a rortier note), and liberal application of matt aluminium garnish in areas such as around the grille and top shoulder line.

Under the bonnet, the RS5 Cabrio ditches the heart of Audi’s previous-fastest four-seat convertible, the $146,000 S5 Cabrio’s 245kW/440Nm 3.0-litre supercharged petrol V6, for a 90-degree quad-cam 4.2-litre direct-injection FSI V8 with chain-driven cam belts and natural aspiration.

On one hand, it delivers a heady 331kW of power at 8250rpm and 430Nm of torque from 4000rpm to 6000rpm via a seven-speed S-Tronic dual-clutch transmission, for a 4.9-second 0-100km/h-sprint time on the way to a top speed of up to 280km/h. That’s 0.4s shy of the RS5 Coupe’s.

Conversely, owners can expect to average 10.7 litres per 100km fuel consumption – a 0.2L/100km rise over the fixed-roof version – a corollary of the 1920kg Cabrio’s considerable 205kg of extra ballast.

In contrast, the S5 Cabrio manages 5.6s, a (speed limited) 250km/h V-max, and 9.7L/100km (for a carbon dioxide emissions rating of 249 grams per kilometre).

Note that in this application the S-Tronic features heavier-duty clutches and a more efficient oil supply for greater response and durability. It has three modes of operation – ‘Drive’, ‘Sport’, and ‘Manual’ (via steering wheel-mounted paddleshifts or a separate quadrant within the gear lever) - with the latter setting holding on to the driver’s chosen ratio right up to the 8500rpm limiter.

The RS5 Cabrio employs Audi’s quattro all-wheel drive system – a purely mechanical set-up featuring a crown gear centre differential and torque vectoring capabilities.

Overall, this quattro application has been modified to channel up to 85 per cent of torque to the rear and a maximum of 70 per cent to the front wheels as needs dictate otherwise in everyday conditions the split is 40/60 front-to-rear.

Additionally, the RS5 Cabrio boasts a rear sport differential. Basically, it works with the ESC electronic stability control system to split drive to whichever of the back wheels needs it to help quell understeer and optimise traction. The ESC can be completely switched off, too.

Like all of B8-series A4-based models, the RS5 Cabrio is built on the company’s MLB (Modulare Längsbaukasten) architecture that first saw the light of day with the current-generation A5’s 2007 debut.

With the front wheels pushed further forward than in previous Audis of this size, it strives to create an inherently more favourably balanced vehicle.

Also to that end, the RS5’s suspension is made up of a five-link front-end arrangement up front and a trapezoidal-link setup out back. Obviously, for its role as a flagship performance convertible, it is in its most extreme state of sports tune, with specific springs and dampers, thicker anti-roll bars, strengthened axle mounts, as well as a 20mm ride-height drop. The standard tyre size is 265/35 R19.

The rack and pinion steering is of a speed sensitive electro-mechanical variety, while the brakes (ventilated discs with eight-calliper pistons up front) use a special ‘wave design’ to help shave weight by 3kg.

From a practicality point of view, the RS5 Cabrio’s rear seat is of the split/fold variety, to increase the boot’s cargo capacity from 320 litres (380L with the soft top in situ) to 750L.

Standard features include Drive Select (which alters the throttle response, steering, transmission change points, and exhaust note), Nappa leather upholstery, Audi’s MMI Navigation Plus, Xenon Plus high intensity discharge headlights, LED daytime driving lights, Bluetooth phone and audio streaming, keyless entry and start, remote-operated roof, electric and heated front seats with neck heating, three-zone climate control, parking radar, an “Acoustic’ hood, wind deflector and a flat-bottomed steering wheel with paddle-shifts and multi-function controls.

Additionally there are literally “limitless” levels of personalisation, such as a $4990 ‘Dynamic Sports Package’ that brings 20-inch alloy wheels, dynamic ride control with adaptive dampers, and an uprated exhaust system.

Other RS5 Cabrio options include a Bang and Olufsen audio upgrade ($1700), adaptive cruise control with side-assist and lane-departure warning ($3200), variable-ratio steering ($2400), sculptured RS ‘bucket’ seats ($4900), and ceramic brakes ($14,500).

2014 Audi B8 RS5 Pricing (Does not include on-roads)

Coupe S-Tronic (a) $155,900
Cabriolet S-Tronic (a) $175,900