Liftback practicality meets epic performance in the RS7 Sportback, but is it different enough to its RS6 Avant sibling?
The Audi RS7 Sportback is the reason the RS6 exists only in wagon form these days for the first time in its decade existence. There is still no large, high-performance sedan in the Audi line-up, though, because the RS7 Sportback is a hatchback (or liftback, just anything but the ‘five-door coupe’ Audi tags it as).
What the Audi RS7 Sportback also is, is seriously quick, with Audi claiming a 3.9 second 0-100km/h – identical to the RS6 Avant. This newly-created ‘RS’ model also measures 5010mm long and weighs in at a sturdy 1955kg – 31mm longer and 30kg heavier than RS6 Avant, with an identical wheelbase.
But the hefty kerb weight is not for want of trying to reduce mass on Audi’s part. Thanks to its hybrid alloy construction, with more than 20 per cent of the body made from aluminium - including the front guards, bonnet, dash cross-member, rear lid and doors - overall mass is claimed to be 15 per cent less than an equivalent all steel body.
All the mechanical bits are shared with the RS6 Avant, meaning the RS7 Sportback is powered by a 4.0-litre twin-turbo V8 that puts 412kW of power and 700Nm of torque through an eight-speed Tiptronic auto transmission to all four wheels.
The quattro all-wheel-drive system is built around a newly developed centre differential that is claimed to rapidly and accurately distribute drive between the front and rear axles. In normal driving, the purely mechanical diff sends 40 per cent of the engine's power to the front axle and 60 per cent to the rear. When required, it can immediately distribute up to 70 per cent of the torque to the front, or up to 85 per cent to the rear.
The engine is claimed to have been designed with immediate throttle response as a key priority, and to minimise turbo lag the intake side of the cylinder heads is on the outside, while the exhaust side is on the inside.
Still with us? What that means is the exhaust manifold is tucked into the valley at the top of the engine’s 90 degree V, along with the twin-scroll turbochargers, and intercoolers, reducing the distance exhaust gases have to travel to power up the turbos (to a maximum of 1.2 bar charge pressure). With that being the case, the inlet manifolds are shifted from their more conventional location on top of the engine, to its outer edges.
To balance performance with efficiency, Audi has incorporated Cylinder On Demand (COD) technology, which at low to moderate load and/or engine speed, deactivates cylinders two, three, five and eight, to create a temporary V4, by closing their valves, shutting off fuel-injection, and cutting ignition. Audi says the system improves fuel economy by around 10 per cent, and claims a combined cycle consumption figure of 9.8L/100km (identical to RS6).
The first seven ratios of the RS7’s eight speed auto transmission are tightly grouped for optimal performance, while top gear is significantly taller to enhance cruising economy.
Underneath, the standard RS adaptive air suspension lowers the car by 20mm, and automatically tunes damping control in line with road conditions and driving style.
Alternately, the ‘drive select’ system allows adjustment of key dynamic functions, including suspension, steering, engine management, exhaust and transmission, through comfort, auto and dynamic modes, while a custom function enables individual fine-tuning of each element.
The electronic stability control (ESC) also has a Sport mode which delays the system’s intervention, to enhance ‘enthusiastic’ driving, and can be deactivated altogether.
On the outside, the RS7 is distinguished by a more aggressive front bumper, with extra vents and a splitter-style spoiler, partly tinted LED headlights, a gloss black honeycomb grill, matt aluminium trim highlights, a rear diffuser and a rear spoiler that automatically extends at 130km/h and retracts at 80km/h (won’t see that rising up in Australia, then).
Standard rims are big, machine-polished, 20-inch forged alloys, riding on 275/35 Z rated rubber, with three 21-inch designs, shod with 275/30 tyres, optionally available.
Inside, the driver-focused cabin is a subtle blend of high-end luxury and ergonomic efficiency. A combination of black Alcantara and leather trim covers the seats and door inserts, with a range of trim elements offered in a choice of brushed aluminium, ultra-high gloss piano black lacquer or carbonfibre.
The heated RS sport front seats feature diamond quilt stitching on their centre panels as well as electric adjustment with memory function.
Black face Instruments are crystal clear, controls simple, and the grippy, flat-bottomed, three-spoke steering wheel, trimmed in perforated leather, adds a race car feel.
The large, retractable, infotainment screen provides access to sat-nav, four-zone auto air-conditioning, Bose surround sound with digital radio tuner (Bang & Olufsen 15-speaker/1200-watt system optional), as well as drive select options. Mobile phone functionality includes a WLAN hotspot for on board web access.
For the RS7’s global release Audi claimed the mountain passes of Austria and northern Italy, as ‘The land of quattro’, and despite the tight, tortuous climbs and descents on the launch drive program this big thumper is in its natural habitat.
The V8 announces its presence with an angry, baritone growl, especially with the drive select system set to open up the exhaust system’s internal flaps, for maximum aural impact.
Although this isn’t the place to experiment with the Tiptronic transmission’s launch control feature, the first few twisting sections are enough to recalibrate your driving consciousness and confirm the car’s sledgehammer performance.
With maximum torque available from 1750-5500rpm, and eight gear ratios to keep the engine in the thick of that band, acceleration is more like a jet than a car.
When the transmission is in manual mode, an F1-style shift light sequence appears in the (standard) driver head-up display. As engine speed increases, green segments in the display form a bar; the bar turns red and blinks shortly before redline is reached. At full throttle in the lower gears, the RS7 rockets ahead with such force, it’s hard to shift early enough to avoid the rev limiter’s raucous stutter.
The roaring engine noise and howling exhaust note dial up the excitement, complete with a staccato crackle on the up-change, as well as dramatic spits and pops on the over run. Power delivery is close to linear, with only the slightest hint of turbo lag discernable.
Electrically assisted steering is quick, and a combination of the carefully tuned, multi-link suspension, quattro AWD system with torque vectoring, and sticky Pirelli P Zeros delivers stunning grip and consistently stable high-speed drive out of corners.
Standard brakes are 390mm discs at the front by six-piston calipers, but ‘our’ test car is fitted with the optional, 420mm carbonfibre-ceramic rotors. Stopping power is huge, and fade non-existent, even on this climb and descend torture test. The RS sports seats provide secure location in quick going, although not at the expense of long-distance comfort.
But, beware of the fact dynamic suspension mode is an absolute filling rattler on anything other than a billiard table smooth surface. Our test example is also riding on optional 21-inch rims, and the switch to comfort is a welcome and rapid relief on second rate sections.
Able to leap small countries at a single bound, the RS7’s top speed is limited to 250 km/h; with optional dynamic package that jumps to 280km/h, and if you sign on for the dynamic package plus, 305km/h is yours.
This is an awesome machine, which combines liftback practicality and cargo carrying ability with stunning performance and superbly honed dynamics. But the big elephant in the room question is whether the RS7 Sportback is better than its RS6 Avant sibling. When it arrives in the first quarter of 2014 the hatchback is expected to cost a bit more than the $225,000 wagon, so expect a circa-$240,000 asking price.
Flip a coin, because the Audi RS7 Sportback drives just as superbly, and thanks to the liftback and impressive 480L boot – only 85L less than RS6 Avant – it even mounts a challenge to the wagon as a similarly practical yet even more stylish full-size performance car.