Audi preparing lightweight, track-focused R8 V10?

First came the R8. Then came the race-spec R8 LMS. Then the V10-powered R8 5.2 FSI, with the roadster version waiting in the wings. The diesel version may have been canceled, but now Audi is said to be working on a light-weight, track-focused version of its flagship supercar.Test mules for what is believed to be the so-called R8 Sport have been seen lapping the Nürburgring (