Audi just recently unveiled its brand new A6, and the A8 has only been on sale for a few months but the brand is soon to augment its lineup up with high performance S models.
Long rumored to receive a turbocharged V8 to replace the naturally aspirated V10 of the previous generation we can now confirm the horsepower output of the S versions. The S6 and S8 will both feature a 4.0 TFSI engine, the S6 will have 408 horsepower while the S8 will have 518 horsepower. It's likely that the S6 (and S7) will use a single turbocharger while the S8 will rely on a twin-turbo setup to deliver the extra 110 horsepower. The regular A8 will also use the 4.0T, delivering 420 horsepower in that application. The S6 and S8 are set to go to production towards the end of 2011 so expect a public debut soon.