Ford seems to be playing a fun little game car enthusiasts like to see: under-rating. Exhibit A is this video from 5.0 Mustang and Super Fords via Hooniverse, which shows the all-new 2013 Ford Mustang Shelby GT500 taking pulls on a dyno. The result is an earth-shaking 609 rear-wheel horsepower. With the standard 15 percent powertrain loss factored in, that puts the GT500 in the neighborhood of 700 hp at the crank. Bear in mind, the dynamometer was Ford equipment, and other manufacturers have been known to supply warmed-over cars for press events. But even if the wick is turned up on the GT500, one thing is for sure. The Chevrolet Camaro ZL1 has some ground to make up, and we look forward to the revival of the muscle-car wars, circa 2013.