2009 Audi S4 Sedan And Avant Feature Supercharged V6

Audi has announced its latest mid-size bahnstormers in the form of the S4 and the S4 Avant. This time around, Audi has ditched the 4.2-litre V8 used in the previous model and fitted a suitably powerful 3.0-litre V6, good for 245kW and 440Nm.

Now, you’d be thinking that’s a lot of kWs to extract from a measly three litres, and you’d be right - there is more to this story. In a departure from their usual penchant for turbo-charging, Audi has bolted a blower (supercharger) to the V6, and that’s going to mean plenty of kWs and Nms from low in the rev range.

Interestingly, Audi is calling the supercharger a “mechanical turbocharger” . However you wish to mince the words, the result is likely to be an Audi with boot-load of torque.

In addition to the supercharger, the completely redesigned 3.0-litre V6 features direct fuel injection and is strong enough to see the S4 sedan accelerate to 100km/h in just 5.1 seconds. The real beauty of this particular performance engine, is that it will also average a very respectable 9.7 L/100km (Avant 9.9 L/100km). Top speed is an electronically limited 250km/h.

The 3.0 TFSI delivers its maximum 440Nm at 2,500 rpm and maintains this constantly until 4,850rpm. In fourth gear, the sedan accelerates from 80 to 120km/h in just 4.4 seconds.

“The 'T' in the 3.0’s TFSI nomenclature no longer merely stands for 'turbo', but rather for the concept of supercharging in general – extensive testing on the big V6 has proven the superiority of mechanical charging. In conjunction with direct injection it is far superior to twin turbochargers, both in terms of packaging and of starting performance and responsiveness."

The supercharger is compact enough to fit easily inside the 90-degree V of the cylinder banks, in place of the intake manifold. Two four-vane rotary pistons counter-rotate inside the turbocharger at up to 23,000 rpm. Two charge-air coolers are integrated into the housing and are connected to a separate coolant circuit. Audi has kept the noise generated by the supercharger to a minimum through “an impressive array of measures” .

The new S4 range continues to feature Audi’s quattro permanent all-wheel drive system. Upon request, Audi can equip the new S4 and S4 Avant with other tempting technological treats, such as a seven-speed S-tronic gearbox, and a new sport differential that distributes torque as needed between the rear wheels.

The new Audi S4 will be unveiled to the public for the first time at the Paris Auto Show from October 2 to 19.

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