Driving the Audi TT concepts

The day he unveiled the TT Sportback concept, the red show car pictured here, Audi's development chief Ulrich Hackenberg told me, "I have always done lots of concept cars." A theatrical pause. "And most of them are now on the road..."

Yup, Audi is serious about extending the TT family. It actually showed, count 'em, four concept TTs this year. First was a three-door with a long roof and more vertical tail, a sort of disinterred Reliant Scimitar GTE. Except it was raised off the ground and called an Allroad. Bit of a daffy idea really, and only really shown to give us a sneak look at most aspects of the production TT Coupe, which hadn't yet been unboxed.

At the Geneva show, right beside the production Coupe, Audi showed a hardcore Clubsport-type TT, with a 420bhp four-cylinder turbo. I've heard several hints that a lighter and sharper TT is indeed on the cards for low volume production, but we also know that it's not the TT RS, because that will use the five-cylinder.

Then in April, after the production Coupe, came a yellow crossover called the TT Offroad Concept. Here is the first big and significant departure, a proper new bodystyle. Note that it was shown in Beijing. The Chinese market doesn't much care for coupes, but it loves crossovers.

Finally in Paris in October, we saw the TT Sportback. It seemed a good time to try and sort it all out. Hackenberg said that, because Audi is going to increase its model range from 50 to 60 by 2020, there is space for what he called "cars in between the regular market segments". And he reckons that because "the TT design language is accepted and iconic" then people would go for these cars if they were part of an expanded TT family.

Provided you accept the premise that the all Germans are going to keep expanding their ranges, the multiple-TT idea makes a lot of sense. After all, the size of the TT Sportback is between an A3 Sportback and A5 Sportback, but it's more cramped than either inside. Same with the TT Offroad, which wedges between an Q3 and Q5. People just wouldn't understand them if they just looked like regular Audis. But the TT design cues - and TT lightweight aluminium construction - would give them vital points of difference.

I've been to Cannes to have a go in them. It was lashing in rain and blowing a gale. The precious one-off cars' minders were sucking their teeth and umming and ahhing. The cars don't have wipers or demisting, and they leak. So I undertook to drive very gently around a cordoned-off area. Doesn't matter. Concept cars are nearly always rubbish dynamically. Driving them is about understanding their package and how they look out there among real cars in real roadscapes, not the indoor confinement of motor-show crowds and spotlights.

First, an explanation from Dany Garand. He's the Canadian designer of the new TT Coupe, so you'd expect him to be a fanatical keeper of the flame. But he is relaxed about seeing how far you can bend and pull at TT-ness. He thinks - and Hackenberg says the same - that in the previous generations, keeping to a just the Coupe and Roadster bodies was unnecessarily limiting.

"Let's stretch the elastic band," Garand proposes. "If you stretch it a bit from the TT you get the TT Sportback. The band copes. The genetics of the TT are not affected. So let's stretch it more, explore the SUV level. It's not so easy to talk about the Offroad Concept as a TT, not compared with the Sportback Concept. But like the TT Coupe, the Offroad forgets the rational. As in a TT Coupe, you accept compromises: the headroom isn't so much, the trunk height isn't so easy, it's tight inside - you accept those boundaries compared with other SUVs. But it's a treat, just as a TT Coupe is a treat."

Both the concepts use TT Coupe structures and design cues. The Sportback is pretty simply an LWB edition of the Coupe, with wider arches for dramatic effect (Garand actually says the wheels are too big, which is pretty much car designer heresy). It's 12cm longer in the wheelbase and 29cm overall longer than the TT Coupe, though just 3cm higher. The seat height is the same as the Coupe, so it really is a four-seat sports car.

"It's a realistic proposal," says Garand. "The wheelbase and overhangs are known in the VW Group. We can build this on the MQB. The steel core and aluminium skin is the same system as the TT Coupe. It uses the TT Coupe bonnet, and the side sections are the same, but the surfaces are a little softer. The TT Coupe is more raw; this is gentlemanly." Inside, the entire dash is the same as the production Coupe.

The Sportback feels like a TT to drive too: you have the same relationship to the car and the dash and the road. It's wrapped around you, and you sit low, looking out through shallow windows. It's only when you look in the rear-view that it's a different proposition. Two adults can fit there. Although not very generously - it's still a selfish car. "If you need more space buy an A5," shrugs Garand. Sure, the extra wheelbase and weight compared with the Coupe would give the chassis engineers a tuning job for a production version, but it should still feel sporty.

The Offroad differs more. It has the same wheelbase as the Sportback, but slightly shorter overhangs. It is 15cm higher, for ground clearance and really quite habitable rear seats. All the exterior panels are unique to the concept. You sit notably higher than the Coupe and Sportback, although still relatively low for an SUV. Inside, there are more concept-ish components - hand-made aluminium parts, and a new transmission shift lever.

Even so, it has blazingly obvious TT design cues. Garand runs over the lines. "The bonnet has extra creases, and a sexy surface bulge at each side, to emphasise the wheel arches. But it has the same theme of grille and lights, and the sharp triangle between them. It has the same kind of wheel-arches, and monolithic sides, with a deep body and shallow glass. The construction of the rear pillar to shoulder to wheel-arch is just the same as the Coupe..."

Both these concepts preview drivetrains that are in active development for various VW Group MQB cars. The Sportback has a 400bhp version of the 2.0 TFSi engine, a DSG transmission and the usual Quattro drive.

The Offroad is a plug-in hybrid. The front wheels are driven by a 2.0 TFSi and a 40kW e-motor. The rear wheels have an 85kW motor, so there's no need for a propshaft, thus making space underneath for a bigger battery. Petrol and electric together give 408bhp. But not on this clonky show car, you can be sure. The steering is heavy and pulls to the left. There's dire wind noise, and most of the cabin electronics are dead.

Never mind. You can enjoy the sense of being in a commanding SUV but with a compact architecture that makes you feel confident on small roads. You want to go quicker. The seat is soft and cushioning but snug and supportive. Audi's calculations say if fully developed it'd have a 31-mile electric range, and it can use an inductive charging mat buried in the road so you wouldn't have to use a mucky cable.

To be honest I'd love to see the TT Sportback go into production, because there are very few cars like that and it'd fit my life. But Americans aren't big on hatchbacks, and Asians pretty well spurn them completely. So you can bet the Offroad is the concept most likely to see production first.

Back in September, Hackenberg was giving much the same signals. Audi had already gone to the trouble of asking gathering potential buyers and asking what they made of the Offroad. "It did well in the clinics. It would do best on the market. But if you ask me from the design side, this one [the TT Sportback] is most harmonious and emotional, my favourite. It's useful for a young family but it's still a sports car."

Hackenberg said in September that Audi would choose within months which of the two would go forward. The decision is still some weeks away, but after that he says we could see the finished article in about two years...