Just to let you guys know, the next generation S4 will get the W8 engine. It is rated at 250hp approx. for the new Passat, so they are estimating around 320hp or so for the S4. It is a basic VR4 connected at the crank, much like the W12 ( 2 VR6's ) Audi felt the NA enigne would be better suited to rival the M3, plus the twin turbo six seems to be problematic.