Carroll Shelby is an automotive icon: "Driver of the Year" in 1956 and 1957, winner of the 24 Hours of LeMans in 1959, a man who could drive Allards, Ferraris or Birdcage Maseratis into Victory Lane.

After the LeMans victory, worsening heart problems forced Shelby to retire. That’s when he decided to produce the AC Cobra supercar. The fastest car on the planet, it won the FIA Manufacturers Grand Touring World Championship in 1965, the only American car to ever do so.

Lee Iacocca was chairman of Ford Motor Company back then, and he and the maverick Texan were friends. In 1964, Iacocca had a new best-seller that he himself had fathered—the Mustang—and he wanted to create some performance models. He asked Shelby's help.

Shelby set up a factory at the Los Angeles airport, tweaked the Ford 289 engine and began producing several hundred GT350 Mustangs a month. They were instantly recognizable by their paint scheme: white body with twin blue stripes over the hood, roof and rear deck. Then Henry Ford II decided that Ford Motor should produce a car that could win LeMans. The task fell to Carroll Shelby.

Shelby gave Henry the Ford GT40. White body. Blue racing stripes. A GT40 won LeMans in 1966 and 1967. A classic photograph captures Henry Ford II jumping with joy as his cars cross the finish line. Shelby could have anything he wanted. He took a 428-cubic-inch engine and dropped it into a Mustang in 1967, creating the first Shelby GT500.

The fun lasted through 1970, when rising insurance rates and tightening pollution control put an end to the muscle car era. Before it was over, Iacocca jumped ship to bail out a struggling Chrysler and Shelby followed. With Shelby's guidance, the awesome V10-engine Dodge Viper was built. At age 68, Shelby drove a Dodge Viper pace car for the 1991 Indianapolis 500.

Fast forward to 2007. The 84-year-old Shelby has undergone heart and kidney transplants and launched the Shelby Children's Foundation to fund heart transplants for indigent children. A percent of profit from all Shelby automobiles goes to this fund. One of those is the 2007 Shelby GT500 Mustang.

True to its muscle car roots, this coupe is a killer on the streets. Under its hood is a 5.4-liter V8 that pumps out an astonishing 500 horsepower. It comes only with a six-speed manual transmission. And, yes, it's white with twin blue stripes from front to rear, over the roof.

This car began life in 2005 at the New York International Auto Show. It's four-valve per cylinder V8 (taken from last year's $150,000 Ford GT) is topped with an Eaton M122 roots supercharger.        

Shelby admits no hands-on involvement. He "advised," including telling Ford to use wider tires in the rear.

Our tester starts at $40,930, adds a $1,300 gas guzzler tax (15 city/21 highway) and ends with a few options at $43,765. A convertible starts at $45,755.

Be forewarned: The 500-hp GT500 is a handful to drive. Entry is difficult and a driver must twist and drop to reach the seat. The speedometer and tachometer are in the wrong positions. The clutch, which must handle massive torque, is very heavy. A driver will likely shift into neutral at a stoplight, rather than tire the left leg by holding down that clutch.

Launching the GT500 is tricky as well. Too little gas and it stalls. Too much and a driver sets rear tires spinning. An all-out acceleration run is very difficult. The ride can only be described as brutal. Every road imperfection is felt. But cornering capabilities match any car I've ever tested. This Shelby seems to know no limits.

Unless it rains, as it did one day on my commute home. The wide tires and abundant horsepower make a terrible combination. The GT500 wanted to slide with every launch; the tires wanted to hydroplane on the slick road.

It also didn't take me long to find out why a sizable gas guzzler tax is applied against this supercar; my work commute consumed exactly $10 worth of gas each day.

The GT500 drew enthusiasm wherever I drove it. It will lead a new "pony car" war, much like America had in the late ‘60s, as Chevrolet plans a new Camaro and Dodge offers a new Challenger soon.

Meanwhile, Shelby is lending expertise to a project to create a clean engine to save the planet from polluting monsters like these muscle cars.

A final note: For 2007, Sarasota's Donzi Marine created a limited-edition 22-foot speedboat in collaboration with Carroll Shelby. It's the Donzi Shelby 22 GT, the only boat ever to wear the Shelby name. It's white with blue racing stripes. Has 425 horsepower. They call it a "muscle boat." And it's $71,000. Love to test that.

Robert C. Bowden produces The Car Place, a Forbes Best of the Web selection, and can be reached by e-mail at [email protected].