This is Audi’s all-new S4 which makes its debut in saloon and Avant (estate) guise at next month’s Paris motor show. It may look much like you’d expect it to, but in a radical move, Audi is turning its back on turbocharging – the S4 is powered by a new supercharged 3.0-litre V6 that pumps out 329bhp and a hefty 406lb ft of torque for a 5.1 second sprint to 60mph and a 155mph top speed.
After years of turbo-charging excellence, why is Audi going with a supercharger?
We’re a little perplexed ourselves, to be honest. While downsizing to a smaller forced-induction engine is a good way of lowering emissions and consumption without affecting performance, we’d have thought Audi’s turbocharging experts would have bolted on one or even two blowers to the S4’s 2995cc direct injection engine rather than a Roots type blower, even one that does spin to 23,000rpm.
‘In conjunction with direct injection it is far superior to twin turbochargers, both in terms of packaging and of starting performance and responsiveness,’ claims Audi’s official blurb. Which sounds like more spin than any supercharger could handle.
What else can you tell me about this engine?
Audi claims the smaller and lighter engine – the blower and a pair of air coolers are compact enough to nestle between the 90deg cylinder banks – benefits the S4’s dynamic balance and shortens the path the air must travel to the engine. It drives all four wheels – the S4 gets Audi’s quattro all-paw layout, natch – through a new seven-speed S tronic transmission.
Although at 142kg the dual-clutch some 40kg heavier than Audi’s six-speed manual, performance is actually faster because of the quick 200millisecond shift times and economy is enhanced because the transmission changes up earlier when driving in auto mode. Official combined economy is pegged at 29.2mpg – a massive 26 percent hike over the outgoing V8 model.