The new Audi RS7 Sportback is yet another addition to the manufacturer’s rapidly growing high-performance ‘RennSport’ – racing sport – range.

You might view this continual increase in the number of derivatives as muddying the water, but there is reasoning to the seeming madness.

By multiplying the variety of bodystyles, powertrains and trims, Audi does not have to rely on one model for success alone; this is why it was the UK’s fourth best-selling manufacturer in 2013 but had no entries in any top-ten best-selling models lists.

The RS7 is yet another extension of that plan. It’s designed to offer the performance and capabilities of the RS6 Avant in a sleeker, more desirable coupé-looking bodystyle.

With the RS6’s powertrain underpinning the body of the A7 Sportback, Audi has created a four door, four-seat hatchback with a twin-turbocharged 4.0-litre V8, eight-speed automatic transmission and permanent all-wheel drive.

It’s an impressive combination, one that promises substantial performance and all-weather tractability thanks to the improved traction offered by Audi’s quattro system.

The Audi’s real ace card, though, is its 4.0-litre V8. Thanks to a BMW M5-imitating pair of turbochargers mounted neatly between the cylinder heads, an air-to-water intercooler and direct fuel injection, it’s capable of producing 552bhp and 516lb ft.

More notably it makes use of a cylinder-on-demand system, which shuts down four cylinders when the engine’s not under much load. In this state it operates as a V4; this helps the RS7 to achieve a claimed economy of 28.8mpg, CO2 emissions of 229g/km and a potential range of 475 miles.

Considering that the two-tonne RS7 is capable of 0-62mph in just 3.9sec – and with the right options, a governed 189mph – its economy is remarkable. To put it in perspective, it’s faster from 0-62mph, cleaner and more efficient than alternatives like the BMW M6 Gran Coupé, Porsche Panamera Turbo and Mercedes-Benz CLS 63 AMG coupé.

Power is sent to all four wheels via an eight-speed automatic transmission, while stability systems (including torque vectoring and an electronically controlled clutch-type rear limited-slip differential) work to make the best of the power and traction on offer. The Audi also features electromechanical power steering, a powerful high-performance braking system and adaptive air suspension.

Standard equipment and features include RS body styling, 20-inch alloy wheels, Audi's 'Drive Select' system, heated electric seats, full LED headlights, a head-up display, sat-nav, a media system, a Bose 14-speaker sound system, parking sensors, a reversing camera, an electric sunroof, four-zone climate control and wheel-mounted shift paddles.

The price is tempting too, at £83,495 for the standard model. That’s considerably less than many of its rivals. The catch, however, is that the options rapidly crank the price up.

We tested a car fitted with upgrades including a sports exhaust, the ‘Dynamic Package Plus’ - which ditches the air suspension and replaces it with conventional dampers and steel springs, interconnected by a hydraulic system to reduce pitch and roll, raises the speed limiter to 189mph, adds carbonfibre-ceramic brakes and dynamic steering - and a carbonfibre styling package, all of which resulted in a total price of over £115,000. That's more than the likes of the V8-engined Maserati Quattroporte GTS.

Over 60 S and RS models have been launched since the designation’s inception in the early ’90s, and the range-topping RS line now stands at nine models strong thanks to this and the RS Q3. So, does the Audi RS7 Sportback deserve to wear the RS badge?

Well, it’s typical Audi A7 inside and anyone who’s driven a recent Audi product will feel right at home. The fact it's like an A7, however, poses a few minor issues.

Front occupants will be greeted by a large amount of cabin space, with plenty of leg- and head-room. Taller rear occupants, however, will find that if they adopt the most comfortable position in the rear seats their head will either be touching or brushing the roof. Otherwise, the rear seats are supportive and a centre folding armrest and air-con controls improve comfort further.

As standard the RS7 comes with heated, electrically adjustable sports seats that are comfortable and supportive. Thanks to myriad adjustments, a decent footrest and an electrically adjustable steering column, it’s easy to find a comfortable driving position.

Many will no doubt still find Audi’s multimedia and sat-nav system a little counterintuitive to use, since the main control dial has the opposite effect to that you might expect. Rotate it clockwise and your selection moves upwards, instead of down. Nevertheless, the system is otherwise easy to use and very capable.

On the plus side, the instrumentation is excellent and an easily readable TFT display, inset between the tachometer and speedometer, grants access to sat-nav functions and other readouts. A heads-up display is also standard, which presents a legible and bright readout in your eye line. It is also capable of displaying sat-nav directions, further reducing the need to take your eyes off the road – something that’s a distinct benefit in a car as rapid as the RS7.

Where it falls down a little is with regards to some minor details. Many of the rubberised and plastic finishes are too grey in colour and feel a little low quality. Likewise, some of the switches feel a little flimsy and don’t befit a car that costs upwards of £80,000.

Although rear space may not be the greatest, the RS7 does at least feature a large 535-litre boot that can be further extended by dropping the rear seats. It’s pleasing to see details like neatly finished plastic covers that obscure the boot’s hinges and electronic lifting mechanisms, which improves the premium feel of the Audi. No spare wheel is fitted as standard, though, which may further irk some buyers.

Out on the road you quickly become aware of the impact of the ‘Drive Select System’, which allows drivers to tailor the vehicle to their preferences. It offers comfort, auto and dynamic modes, which adjust the way that key elements like the engine, transmission, suspension, steering – and even the exhaust and seatbelt tensioner – behave. An individual mode allows you to configure it to your precise demands.

In comfort mode the RS7 transpires to be a relatively cosseting car to drive. Its taut and composed ride borders on the overly firm but, with light steering, well-judged throttle and brake responses and good visibility, it's not intimidating or tiring.

You do feel a lot of minor surface imperfections though, so those who don't want to be constantly massaged by gentle vibrations through the seat or steering column should best look elsewhere. Given its performance credentials and design, this small compromise is just about acceptable. At cruising speed the RS7 is acceptably refined, although rough surfaces can cause a notable amount of road noise. Wind noise is very low.

Through corners the steering is precise and direct enough to inspire confidence that the RS7 will go where you point it, but there's little in the way of feedback. You're left placing your trust in the RS7’s stability systems and what little you can feel through the seat.

Audi's torque vectoring and limited-slip differential makes it very easy to maintain or adjust your line mid corner, without drama. Simply turn in further, even while applying power, and it simply carries out your commands as expected.

Switch in to Dynamic mode and things change dramatically. Besides a more vivid engine response, and a louder exhaust note, virtually all roll and pitch is dialled out instantly.

The Audi seemingly adopts a terrain-following mode, with the suspension cancelling out all vertical movement for improved precision; the trade-off is a crippling and neck-tiring ride as the body resolutely follows the road surface with no damping. If you're in the mood for something edgy and devastatingly quick, fine, but in regular use it's intolerable.

In dynamic mode the steering also becomes weightier, seemingly increasingly so as the speed and steering angle increases. The additional heft does lend you a more confident feel but the extra effort required, just off centre, can make the RS feel unwieldy as the initial lock is slow to bite and apply. Its variations in weight can also feel a little unnatural, particularly during faster, sharper corners.

Very quickly you either make the decision to leave the car in comfort mode, or you set up your own 'individual' calibration. We found the RS7 at its smoothest and most rewarding with the engine, exhaust, differential and belt tensioners in 'Dynamic', and the suspension and steering in 'Comfort'. Auto offers a halfway house, but it's preferable to know how the car will react at any given moment.

It's almost impossible to fault the Audi's V8 engine, though. Once the RS7 gets off the line - and the revs climb over 2000 - it pulls hard to the redline. Throttle response is crisp and vivid, and with the optional sports exhaust in Dynamic mode there's plenty of aural theatre.

Just off idle the RS7 emits a low, baritone note reminiscent of a larger displacement AMG, and an aggressive roar permeates the cabin through the rev range. Step off the throttle, even at lower speeds, and you'll be serenaded with pops, bangs and crackles, evoking memories of the UR-Quattro. It's a very vibrant, capable and gratifying powerplant. Audi's cylinder-on-demand system also functions entirely unobtrusively, with no noticeable effect on how the car drives.

The eight-speed tiptronic transmission proves adept at quietly and smoothly shifting through each of its ratios, when left to its own devices. In either Sport or Normal mode it does a very good job of picking the right gear, and in manual mode it's satisfying to see that you can fling the engine against the limiter with abandon - it won't override you and shift up. The catch is, unfortunately, that it can be a little reluctant to change up or down when you want it to.

Consequently you're left either having to increase your braking effort in a corner, or bouncing noisily and slightly embarrassingly against the limiter as you attempt to make a swift overtake.

You quickly learn to pre-empt changes by a second or two, in order for them to occur at the quick moment, but you're always left thinking it's best left in automatic mode. For more enthusiastic drivers this will prove frustrating; it's not as intuitive or direct-feeling as a dual-clutch auto transmission.

During braking the RS7 feels stable and the optional carbonfibre-ceramic brakes, the discs of which are reputed to last for up to 183,000 miles, offer up almighty and fade-free stopping power. No doubt the conventional items do so too.

The Audi RS7 Sportback is very much a car that’s capable of showing you what’s possible, in terms of speed and cornerning, thanks to its technology and battery of stability systems.

For many buyers this will be ideal; they will be looking for a stylish and premium-looking car that’s capable of effortlessly and rapidly transporting its occupants and luggage over vast tracts of road.

Some may find the RS7 somewhat disingenuous, however, with its falsified feedback, desire to be left in automatic mode and continual (although unobtrusive) interference - and a little off-putting as a result. It fails to offer the same degree of engagement and communication that rivals such as the Porsche Panamera deliver, and while its engineering is first-rate the interior and general finish lags behind that of its rival.

There’s no denying that, from either perspective, it’s still a rewarding car to drive – because of its sheer pace, high degree of mechanical grip, immense traction and glorious noise. Consequently it's justifiably worthy of bearing the RS badge.

It’s also satisfying to know that - although you might not be as thrilled through the corners as much as you would in its rivals - that you can deploy all of the available power without any undue concerns. For those looking to use their cars to the fullest of their extents throughout the year, this is a critical point.

While Audi might argue that price is a non-issue when you’re looking at spending this much, it still bears some consideration. Tick several options, as Audi suggests most will, and the price for the RS7 easily spirals well over the £100,000 mark, equivalent to that of the similarly capable all-wheel-drive Panamera Turbo.

Audi’s fast four-seater may be a phenomenal performer and better equipped as standard, but there’s no doubting that the Porsche would be the more cohesive and rewarding option; it also feels the more premium product. If you're into the six-figure range it also may be worth considering the likes of a nearly new Bentley Continental GT.

Keep close to the standard specification, though, and the Audi RS7 Sportback offers serious all-weather ground-covering capabilities with a modicum of practicality for a comparatively inexpensive price.

Top 5 Super saloons

  • Jaguar XFR
    Not only is the XFR the class leader, it is also exceptional value compared to rivals

    Jaguar XFR

  • Mercedes-AMG C 63
    Mercedes-AMG C 63 saloon is priced from £59,800

    Mercedes-AMG C 63

  • BMW M3
    The M3 packs a twin-turbocharged 3.0-litre straight six that produces 425bhp and 405lb ft

    BMW M3

  • Mercedes-AMG E 63
    The old 6.2-litre V8 has been dropped in favour of a twin-turbo 5.5-litre V8

    Mercedes-AMG E 63

  • Jaguar XJR
    The Jaguar XJR offers monstrous, relentless performance

    Jaguar XJR


First drives

Find an Autocar car review

Driven this week

  • Car review
    23 September 2016
    Aston kicks off its ‘second century plan’ with an all-new turbo V12 grand tourer
  • Ford Ka+ 1.2 Ti-VCT 85
    First Drive
    22 September 2016
    A rounded, refined and well-sorted bargain supermini – once you’re used to the confusing role redefinition imposed on the once-cheeky Ka
  •  Maserati Ghibli Diesel
    First Drive
    22 September 2016
    Maserati releases another range of updates for its range best seller, the Ghibli. We've driven the diesel version, but there's little improvement on before
  • Tipo Front
    First Drive
    21 September 2016
    New Fiat Tipo offers impressive space and practicality for a reasonable price. We try the 1.6 diesel on the demanding roads of North Wales
  • Seat Ateca 1.4 TSI 150
    First Drive
    20 September 2016
    The Seat Ateca 1.4 TSI 150 makes perfect sense: it's spacious, tidy to drive for an SUV and cheap to run