Audi shows off its frugal side

Miser: The S5 Sportback is the most frugal car in its category. Photo / Supplied

Audi's five-door version of its sleek S5 coupe is being introduced at the Frankfurt Motor Show next week.

It's one of a trio of newcomers Audi's showing at Germany's best-known vehicle exhibition. While the graceful S5 Sportback is about go and show, the others are optimised for good fuel economy and low emissions.

The S5 Sportback promises to be more than just an expensive good looker. Audi says it does the 0 to 100km/h sprint in a little over five seconds and has an electronically limited top speed of 250km/h. Fuel consumption of 9.7 litres per 100km is said to lead its category, although the other newcomers do much better.

It's powered by a supercharged 3- litre V6 that delivers 245kW and 440Nm of torque between 2900 and 5300rpm. A seven-speed S-tronic dual-clutch transmission and quattro permanent all-wheel drive are standard. And a sport differential that variably distributes power to the rear axle is optional. Power goes to the road via 18-inch aluminium wheels and 245/40 tyres.

It will be coming to New Zealand in the first quarter of 2010.

The other newbies are the A4 3.0 TDI clean diesel quattro and the A3 1.2 TFSI.

The "green" A4 uses the 3.0 TDI diesel engine first seen in the supersized Q7 SUV. It already complies with the Euro 6 standard, expected to become law in 2014.

Low emissions are partly achieved by a new common-rail injection system, advanced pressure sensors in the combustion chamber and a high-performance exhaust recirculating system. Outside the engine, a DeNOX catalytic converter at the end of the exhaust reduces residual nitrogen oxides. Further upstream, a pump injects an additive called AdBlue into the hot exhaust flow. This aqueous solution decomposes into ammonia, which splits the nitrogen oxides into nitrogen and water.

Fuel consumption's pretty good, averaging 6.7 litres per 100km, and it's quick, too. It needs just over six seconds to go from zero to 100km/h. Like the S5 Sportback, top speed is electronically limited to 250km/h. Audi expects to bring the car to New Zealand next year.

The newest A3 model blends super economy with reasonable performance. Its 1.2 TFSI motor generates 77kW and 175Nm of torque, which is on tap between 1500Nm and 3500rpm. The engine has been developed to have low friction, incorporates turbocharging and direct fuel injection. It will first be paired with front-wheel drive and a six-speed manual transmission.

The car runs 0-100km/h in just over 11 seconds, can do 190km/h and, on average, consumes 5.5 litres of fuel per 100km.

Despite all that, it's unlikely the car will come to New Zealand, where performance is preferred.