What we have here are two Sedans from Audi with some differences, such as the model year, starting price, and horsepower. First of all, there is a $28,500 difference in the base MSRP. The 2013 Audi S8, an older vehicle by three model years, has a higher starting price than the 2016 Audi A8. And finally, the 2016 A8 produces fewer horsepower than the 2013 S8. Among similarities are the body structure, market segment, fuel economy, ground shadow size, height, and maximum occupancy.