GT500 gallops ahead

It's a good thing that Ford's media types picked a closed course for the launch of the 2011 Shelby GT500. Really, where else could you fully flog the most potent Mustang model ever produced for public consumption and escape with your driver's license and life intact?

Looking good and going fast hasn't always been a Mustang hallmark. But in recent years Ford has focused on infusing its decades-old steed with both traits and the Mustang-based Shelby GT500 is proof that the automaker remains resolutely passionate about performance.

The Shelby GT500 gets its name from Carroll Shelby, who is perhaps best known as the creator of the 1960s-era Cobra sports car. But Shelby was also the man most responsible for developing the original racing Mustangs. Beginning in 1965, Shelby launched a limited line of high-output Mustang GT 350 and GT500 street models that in turn helped solidify the original pony car's legendary status.

Roaring around the racetrack today, it's easy to see -- and hear -- that the Mustang is all about power. A new V-6 makes more than 300 horsepower (up 90) and a new 5.0-liter V-8 in the GT makes 412 (up nearly 100 horsepower from the previous 4.6).

And the GT500? Well, after a four-decade absence, the nameplate returned for the 2007 model year fitted with a 500-horsepower 5.4-liter supercharged V-8 sporting four valves per cylinder. The engine was a direct descendent of the engine found in the Ford GT supercar that made 550 horsepower. The GT is gone now, of course, and the Mustang was boosted to 540 horses when it received a styling makeover for 2010.

However, the cast-iron-block 5.4 V-8 has now been replaced with an all-aluminum version that's lighter by a whopping 102 pounds. Part of that reduction comes from using a special spray-on metallic cylinder coating that replaces traditional thick -- and heavy -- protective metal liners.

Carroll Shelby, now 87, who advised on the GT500's development, commented, "It might not be as sexy as adding more horsepower or bigger brakes, but shaving pounds off a car is the single smartest move you can make."

The new engine is rated at 550 horsepower (a gain of 10), while the 510 pound-feet of torque remains unchanged. However, more of the available torque is achieved at a lower rpm range, which makes it easier to get to. You really notice this when shifting through the first two of the manual gearbox's six gears (an automatic transmission isn't offered).

This beast isn't really a beast on fuel as Ford expects the GT500 to achieve 15 mpg in the city and 23 on the highway, a gain of 1 mpg for each segment when compared with the 2010 model.

Improvements in performance and fuel consumption have gone hand in hand with numerous cabin enhancements. For example, the Special Vehicle Team (SVT), which is in charge of the GT500 program, has added more insulation to reduce wind and road noise. That means there's less of the good noise -- the high-pitched whine of the supercharger -- but, interestingly, there's just as much exhaust rumble as before.

Convertible GT500s also benefit from a more rigid (by 12 percent) body structure that, according to one SVT engineer, makes this body style "act and feel more like a coupe without degrading the ride."

Usually, replacing the fixed roof with a relatively flimsy convertible top would be like cutting the cables on the Golden Gate Bridge. For this reason, few high-performance coupes -- which require roof to tie the car together -- are seldom offered as convertibles.

The 2011 GT500 benefits from a new $3,500 SVT Performance Package that includes a stiffer suspension, limited-slip differential, more front and rear downforce, slightly lowered ride height and unique Goodyear Eagle F1 SuperCar G:2 tires mounted on lightweight 19-inch front and 20-inch rear wheels. After completing several laps driving a TrackPack-equipped GT500, the verdict is this: Absolutely do not leave the dealer's showroom without it.

You can add other options, of course, including a giant glass roof and a navigation system, but they will obviously further inflate the car's $49,500 base price ($54,500 for the GT500 convertible).

Both prices seem reasonable considering that a 505-horsepower Corvette ZO6 -- which is considered a bargain in most performance circles -- lists for more than $75,000. Conversely, you could scale back to the 412-horsepower Mustang GT for $30,500 and pocket the $19,000 difference. If you never drove the GT500 for comparison, the GT would likely be one of the best rides you've ever had.

Still, if you have a healthy credit limit and want the best of the best -- at least when it comes to Mustangs -- the amazing Shelby GT500 is tough to pass up.