Audi 'R4' e-tron: full details

Audi’s latest e-tron concept is the strongest hint yet at the firm’s intentions to build a smaller, lighter sports car known as R4.

The new two-seater has the same name as the bigger, more powerful concept car revealed at last year’s Frankfurt motor show and driven by Autocar last month.

However, this car is significantly smaller and, uncharacteristically for an Audi concept car with clear sporting intentions, it’s rear-wheel drive.

The latest e-tron, revealed at the Detroit motor show, is also more than just a one-off showcase for Audi’s zero-emissions plans; it confirms that Audi chairman Rupert Stadler has already given the go-ahead for a new, small, mid-engined sports car.

According to Audi sources, this new e-tron concept provides strong clues to a new production car that will be sold as the R4. It will share key components with the showroom version of Volkswagen’s BlueSport concept, and possibly a new entry-level Porsche roadster, when it arrives in showrooms sometime between now and the end of 2013.

Picking up on the styling theme from the first e-tron, the low-slung concept has a traditional sports car silhouette, with a long bonnet, a heavily curved roofline and a stubby rear end. However, the body is a lot edgier, with hard crease lines, taut surfacing and a heavily sculpted rear end providing it with a highly contemporary look that sets the tone for the upcoming R4.

Elements such as a large single-frame grille housing carbonfibre fins to direct air into the front end, and distinctive LED-enhanced headlamp graphics, clearly set the new car out as an Audi from the front. However, certain features at the rear end are highly reminiscent of recent Aston Martin models — in particular the rear light graphic.

Styled by a small team working under Audi’s British-born manager for concept car design, Steve Lewis, this e-tron was completed in just four months following a go-ahead from senior management last September.

“We wanted to push the electric car in a sporty direction without making it appear too futuristic,” said Lewis. “It was important to give the car a uniquely technical appearance in a bid to get across the message of the electrical package that lies beneath.”

At 3930mm long, 1780mm wide and 1220mm tall, the concept is shorter, narrower and lower than the original e-tron and the current TT. It rides on a wheelbase that, at 2430mm, is 170mm shorter.

At the heart of the e-tron is a new electric powertrain. It uses a pair of motors mounted within the rear axle producing a total of 201bhp along with a whopping 1954lb ft of torque — all of which is sent to the rear wheels only via a torque-vectoring differential.