2011 Ford Shelby GT500 Mustang

With shaved pounds and a supercharged engine, the Ford Shelby GT500 has the stellar performance to complement its stunning piece of design. Lighter by a little over 100 pounds (with the coupe weighing 3,820 pounds and the convertible packing in 3,969 pounds) yet more balanced and fuel-efficient, the 2011 Ford Shelby GT500 is a

At first glance, the news in the engine bay isn't all that promising. It's still a 5.4-liter supercharged and intercooled V8 backed by a six-speed manual transmission. Peak power climbs just 10 hp from 540 to 550 thanks mostly to a increase in exhaust-pipe diameter from 2.5 inches to 2.75 (The larger pipes reduce back pressure). Torque remains at 510 lb-ft, but it occurs 250 rpm lower, at 4250. A larger intercooler has also been added, for more consistent performance.

The argument could be made that the GT500 didn't need more power. What it really needed was less weight, especially over the nose. And thanks to an aluminum block, the engineers trimmed 102 off the front, which should be a welcome change. More on that in a bit.

Like all Mustangs, the GT500 now has electric power steering, and SVT used this opportunity to retune the effort curve. The stock suspension has not been changed, but there's a new optional Performance Pack that should tighten this car down even more. With this optional model, the front spring rates are 20 percent stiffer, the rears go up eight percent and there's also a stiffer rear antiroll bar. Ride-height and rake changes (it's slightly lower in the front) attempt to increase corner-exit traction.

Perhaps most critical are what's in the fenders: New forged 20-inch wheels are lighter than the 19s and wear wider, Mustang-specific Goodyear performance tires. SVT engineers claim that the Performance Pack car is nearly 3 seconds a lap quicker around Gratten Raceway, a Michigan track that the local car companies use for testing. For those not accustomed to racing times, 3 seconds is an eternity. Acceleration figures should be better, but by only a tenth of a second or so. We expect it to hit 60 mph in the low 4-second range and cross the quarter-mile in less than 12.5 seconds.

Cosmetically, the changes are minor. Performance Pack cars will wear those massive wheels, and their stripes will be slightly thinner. Only fanatics will recognize the difference.

In other news, a glass roof becomes available on the GT500 for the first time. The convertible model returns, but it's been stiffened structurally by 30 percent and now sports standard 19-inch wheels.

Interior