According to the UK magazine Autocar - a reasonably reliable source of new model information - the next Audi RS6 model based on the new A6 platform will not have the V-10 engine from the Gallardo. Apparently, the packaging cannot be optimised for the new chassis. Therefore, it will utilise a turbocharged version of the new V-8 4.2 litre fsi engine. I find this disappointing, not only because I prefer the instaneous throttle response you get from a naturally aspirated engine, but also the forthcoming BMW M5 will have a V-10 good for 500 bhp. I find it to believe that the V-10 won't work in the new A6, especially as there have been rumours on this website of a V-10 in the S4 platform.
I wonder whether Audi is saving the V-10 for the S8?