For 2011, power in the GT500 has only been upped by 10 ponies, and the 0-to-60 time has remained virtually untouched. So what's the big deal? Instead of blowing out the power, Ford's engineers sought to build an engine as efficient as it was powerful. To do so, there were big and small changes made. To reduce friction and wasted energy in the cylinder housings, Ford patented a Plasma Transferred Wire Arc technology that uses a composite to help the pistons chug along more smoothly. Even more importantly, the V8 received a new aluminum block that is 102 pounds lighter than last year's cast-iron block. This improves everything: handling, acceleration, and fuel economy. This is the first Shelby GT500 to be exempt from the gas-guzzler tax. Drive with a clean conscience.