The 2008 Audi R8 is available as a 2-door, 2-seat coupe. Starting at $109,000, the 2008 Audi R8 (M6) is powered by a 4.2L , 8 -cylinder engine mated to a manual transmission that returns an EPA estimated 13-mpg in the city and 20-mpg on the highway. The top of the line 2008AudiR8Base , priced at $ 118,000 , is powered by a 4.2L , 8 - cylinder engine mated to an automatic transmission that returns an EPA estimated 13-mpg in the city and 18-mpg on the highway.