First rumors said the 2010 Audi S4 would share its powertrain with the S5. But this rumors are incorrect as the 2010 S4 will be powered by an all-new forced-induction 3.0-liter V-6 that will generate something close to the 340 hp.
The reason is quite simple: fuel economy. Audi’s strategy is to deliver comparable or improved overall performance by toeing the line on weight and maintaining power output by using forced induction on a smaller displacement engine. Doing so will boost a manual transmission S4’s fuel economy on the European cycle to 23.3 mpg compared with only 19.4 mpg for the V-8 S5. That’s an efficiency gain of 20%.
A less powerful, 290-hp, 310 lb-ft version of the engine will be the base offering in the A6 Quattro, replacing the 3.2-liter V-6. Known as TFSI, which in the past has been Audi’s internal moniker for four-cylinder turbos, the new engine may be referred to as the 3.0T in the model name, possibly indicating a twin-charged system using both a supercharger and a turbocharger. While Volkswagen has a “twincharger,” Audi has not yet offered such a system. At the very least, we expect the new V-6 to be supercharged, although what will allow the S4’s version to generate 50 or so more horsepower is still a mystery.
Audi will debut the 2010 S4 this autumn, probably at the Los Angeles Auto Show.