Though Ford put all of its considerable marketing muscle behind the Mustang when it launched in 1964, even it couldn't have predicted just how popular the car would prove to be. However, as the orders mounted up so did the fear that interest could dissipate just as quickly and so something needed to be done to keep momentum going.

Ford hit upon the idea of getting the car some serious racing credibility and decided to call upon the skills of Carroll Shelby who had been working miracles with the Cobra, a ferocious race car he'd created by taking a little lightweight British sportscar -- the AC Ace -- and sticking a big Ford V8 engine in it.

Shelby decided to build a street-legal racing version of the Mustang, which would compete in the Sports Car Club of America B-Production class races in 1965.

Competing cars weren't allowed to have a modified engine and a modified suspension set-up -- one or the other only, and could only have two seats. Manufacturers were required to build at least 100 production examples for public sale, meaning that the changes couldn't too adversely affect price.

Even with his hands tied by the restrictions, Shelby worked his magic. He replaced the standard hood with a lighter fiberglass version with an air scoop. He fitted a rear differential, bigger front disc brakes, a four-speed gearbox and overhauled the suspension with better shocks, mountings and antiroll bars.

As for the engine, he kept the car's standard 271hp 4.7-liter V8 but changed the carburetors and valve covers and improved its breathing and in the process found a further 35hp. The final touches were to remove the rear seats, bolt a spare wheel in the space created by their removal, and to paint the exterior Wimbledon White with Guardsman Blue rocker stripes.

And as for its name, the story goes that Ford was putting pressure on Shelby and his team to come up with something catchy to call the car. Shelby told one of his staff to count the number of steps from the office to the garage where the car was being developed. There were 347. So he rounded it up to 350.

The GT350 dominated the B-Production class races wining the series three years in a row and in the first year alone, Ford sold over 500 to the public. The success marked the start of a relationship between Shelby and Ford that continues to this day. Fifty years on, the current generation Ford Mustang's top model is the GT350.