The TT Sportback was the third in a line of critically acclaimed TT-themed concept cars to be unveiled in 2014, following on from the TT Shooting Brake that was shown as a precursor to the production coupé at the Detroit motor show back in January, and the high-riding TT Offroad that appeared in an arresting yellow paint scheme at the Beijing motor show in April.
All three are individually described as possessing a realistic chance of entering production, but it is no secret that the TT Offroad and TT Sportback are Stadler’s preferred options for production.
That’s because their five-door layouts offer greater everyday practicality than that of the three-door TT Shooting Brake, even though the Shooting Brake’s commonality with the coupé and roadster would make it considerably cheaper to build, according to those in the know.
As the two Audi concept cars in question sit nose to nose on a windswept promenade in Cannes, waiting for me to sample them on the move for the very first time, the complexity of Stadler’s decision is brought into clear focus.
Concept cars are often nothing more than a flight of fancy with little in the way of production relevance. However, there is real substance to the appearance and mechanical package of each of the potential TT models.
They are both sufficiently convincing in the looks department and possess the sort of sound engineering required to become one of the 10 new models that Audi plans to add to its line-up by 2020.
Styled under the leadership of new design boss Marc Lichte, both the TT Offroad and TT Sportback show the heavy influences of the Bauhaus lineage that has influenced the look of the TT coupé and roadster since their introduction in 1996. So although they’re aimed at differing markets, they continue to remain true in appearance to the cars that inspired their creation.
Each features its own interpretation of Audi’s latest six-corner single-framed grille, trapezoidal-shaped headlamps, clamshell bonnet, prominent wheel arch elements, defined shoulder, shallow glasshouse and plunging C-pillar treatment.
But in a clear departure from the traditional three-door TT models currently on sale, both of the potential new TTs feature a more versatile five-door layout aimed at making them appeal to a whole new group of buyers. The TT Offroad boasts an angled tailgate whereas the TT Sportback receives a large fastback-style opening.
Underpinning the potential new TT models are variations of the MQB platform of parent company Volkswagen. To accommodate its rear doors and provide adequate rear seat space for two adults, the TT Offroad’s wheelbase runs to 2630mm and the TT Sportback’s is slightly longer, at 2637mm. This is a respective 132mm and 125mm longer than that of the latest TT coupé or roadster.
One potential problem standing in the way of a possible production green light for both concept cars, though, is their apparent similarity in dimensions to existing Audi models. With a length of 4390mm, width of 1850mm and height of 1530mm, the TT Offroad is just 15mm longer, 20mm wider and, because of its relatively modest ground clearance, 60mm lower than the recently facelifted Q3.
Meanwhile, at 4470mm long, 1890mm wide and 1380mm tall, the TT Sportback is 14mm longer, 94mm wider and 36mm lower than the A3 saloon.
The relatively short driver’s door of the TT Offroad motors out at a touch of its recessed handle. Slipping inside, you discover that its interior, as that of the TT Sportback, is based closely on the new TT coupé’s. The two cars share the same high-quality dashboard, centre console, switchgear, multi-function steering wheel and heavily bolstered front seats.
Among the highlights is Audi’s new virtual cockpit display. It uses a 2.3-inch TFT monitor set within the instrument binnacle and is operated by a rotary control placed on the centre console.
Recalling the driving environment of the TT coupé, you sit quite low, with the waistline up around shoulder height. Resisting the temptation to turn the high-riding TT into a fully fledged five-seater, Audi has given the Offroad concept individual rear seats with integrated headrests, providing it with accommodation for up to four – a layout mirrored by the TT Sportback.
Hinting at plans to bring hybrid drive to the TT line-up for the first time, the TT Offroad showcases a powerful petrol-electric drivetrain in combination with a multi-plate-clutch four-wheel drive system.
Mounted transversely up front is a turbocharged 2.0-litre four-cylinder petrol engine that produces 288bhp and 280lb ft. It sends power to the front wheels via a six-speed dual-clutch gearbox, which houses an electric motor that provides an extra 54bhp and 162lb ft.
Within the rear axle is a second electric motor that produces 114bhp and 199lb ft – all of which is channelled to the rear wheels via a single-ratio gearbox. Energy for the electric motors is provided by a 12kWh lithium-ion battery.
Audi’s computer simulations point to a 0-62mph time of just 5.2sec and a top speed of 155mph. But when we piloted the stylish SUV up and down the promenade, the pace was a good deal more relaxed and achieved purely in electric mode, in which it operates solely in rear-wheel drive using power from the rear-mounted electric motor.
Officially, the electric range is put at 31 miles at speeds up to 81mph. In hybrid mode, during which all three power sources are called upon for propulsion, the TT Offroad is claimed to have combined average economy of 149mpg – a figure that corresponds to average CO2 emissions of just 45g/km and an overall range of 547 miles.
Previewing plans for its upcoming R8 e-tron, Audi has also provided the TT Offroad with wireless charging, which allows the car simply to be parked in a suitable position for its battery to be recharged in a similar timeframe to that offered by a conventional cable.
Residing under the clamshell-style bonnet of the TT Sportback is a more conventional drivetrain in the form of a heavily tuned version of the turbocharged 2.0-litre engine that is used by the latest TTS coupé and known internally as the EA888.
Mounted transversely, it is claimed to deliver an additional 85bhp and 52lb ft over the standard unit used by the TTS coupé, providing the TT Sportback with a stout 395bhp at 6400rpm along with 332lb ft of torque on an extraordinarily wide range of revs between 2400rpm and 6000rpm.
Among the power-enhancing modifications used to achieve a specific output tantalisingly close to 200bhp per litre is a new turbocharger tuned to deliver a maximum 1.8 bar of boost pressure, a reworked cylinder head with increased gas flow rates, revisions to the variable camshaft adjustment and the two-stage variable valve-lift system and indirect fuel injection on part-throttle loads for improved combustion efficiency.
The heady reserves are channelled through a six-speed S-tronic dual-clutch automatic gearbox with remote steering-wheel-mounted paddles and a multi-plate-clutch four-wheel drive system mounted within the rear axle for improved front-to-rear weight distribution.
So configured, the car is capable of a claimed 0-62mph time of just 3.9sec, which is 0.7sec quicker than the TTS coupé, and a 155mph top speed.
As with its sister car, though, we were only able to drive the TT Sportback at a mild pace within the confines of a car park. With its front seats positioned at the same height as those in the TT coupé and the steering wheel near to vertical, it feels a good deal more sporting than its five-door layout suggests. But with relatively small door apertures, getting in to the rear is not easy at all.
The TT Offroad and TT Sportback are superbly constructed by concept car standards and highly convincing as conveyers of how Audi intends to expand the TT line-up.
If I was a betting man, I’d put my money on the TT Offroad reaching production first, despite its apparent similarities with the existing Q3. With the popularity of compact SUVs as strong that they are right now, it would undoubtedly provide stiff competition to the Range Rover Evoque.
For me, though, it is the TT Sportback that holds greater fascination. Bolder and more stylish than the A3 saloon, it would be the perfect foil to the Mercedes-Benz CLA. Over to you, Rupert…
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