The next-generation RS4 will feature a 3.0L supercharged V6. The same basic unit will also power the somewhat tamer S4, though it will no doubt be in higher tune in its RS application. The outgoing generation RS4 is powered by a 4.2L V8 rated at 414hp (309kW). Power figures for the new engine aren't yet known, but the new supercharged V6 is expected to be thoroughly sport.
Speculated figures place the S4's version of the powerplant at 350hp (261kW). Adding the requisite power bump to the RS4 model would place output back on par with the V8 model, and thanks to the supercharged induction, a very wide torque band would be available from an even lower RPM, reports Sweden's Auto Motor und Sport - all ingredients for very strong performance.
The original Audi RS4 was a forced-induction V6, though it was a twin-turbo unit generating 261hp (195kW) from its 2.6L displacement. Efficiency ratings of forced induction technologies have advanced somewhat since the first twin-turbo RS4 was built in late 1999 and the addition of twin-turbos or any dual-charging system to the current RS4 has been dismissed as prohibitively complex and expensive for the gains over a single supercharger design.
Whether Audi will actually follow through with the return to a forced-induction six-cylinder or not remains to be seen, but with impending fuel and emissions standards tightening around the world, even the high-performance luxury carmakers will have to change to keep fleet averages in line.