With all this media talk of a gas electric plug-in hybrid clean diesel hydrogen fuel cell future, someone forgot to tell Mercedes that the horsepower war is over. Sure, the new BMW M3 has a 414hp V8, trumped by the Audi RS4's 420hp eight pot. But who gives a shit? The new automotive arms race: building and selling enough small, high-mileage, low-profit vehicles that various government agencies will let you sell large, low-mileage, high-profit vehicles. Meanwhile, the Mercedes C63 AMG.