Ford Mustang Shelby GT350 : Fine Lines

Inside, aircraft-style eight-centimetre-wide racing safety belts were fitted and the rear seat was discarded, replaced by a fibreglass shelf where the spare tire was perched. A Cobra-style wood-rim steering wheel was also installed which meant relocating the horn to a dash-mounted toggle switch.

Two different versions of the GT 350 were originally made: an 'S' version for the general public; and about two-dozen strictly-for-racing 'R' models (out of a total-first-year production of 562 cars). The competition GT 350 featured a blueprinted engine fitted with a special racing cam, oil cooler, larger-capacity radiator and 32-gallon fuel tank. The 340-360 horsepower that resulted from these modifications turned the GT 350 into a major contender on the track.

In its first year, the new Mustang proved its competitive worthiness, winning nearly every race it entered in convincing fashion. It also didn't hurt that some of racing's top drivers, including the legendary Mark Donohue, were behind the wheel.

The street-going GT 350 cars were no slouches, either, and were capable of 6.5-second 0-60-m.p.h. (96 km-h) times and could run the quarter-mile in 15 seconds at 95 m.p.h. (150 km-h)

On the negative side, the GT 350 was a handful to drive, demanding the driver's full attention. The non-power steering required considerable brute force and the heavy-duty brakes demanded an equal amount of leg strength to get the car stopped. If that wasn't enough, your ears took a beating from the engine racket booming into the hollowed-out interior while your eyes and lungs filled with high-test exhaust fumes.

As much as the GT 350 was loved for its purity, so suffered the everyday folk who found one parked in their driveway. And so began the GT 350's slow metamorphosis to street-friendly from race-ready. Some might call it compromise, but others would argue it was essential to give the car broader appeal and help stave off its eventual extinction.

So, in 1966, several modifications were made, including rerouting the exhaust system to exit out the rear, changing the fiberglass hood to steel, adding side scoops to assist rear brake cooling and knocking out the fastback's rear-side louvers in favour of tiny plastic windows.

A new option was a rear seat that could be installed in place of the spare-tire shelf for those wanting both passenger room and performance.

Not surprisingly, nearly 2,400 GT 350s -- a leap of more than 1,800 units -- were sold. Of that total, 1,000 were dubbed the Shelby GT 350H and delivered to Hertz, which added the cars to its rental fleet. As a consequence, a number of these automatic transmission-equipped cars with their distinctive black paint and gold stripes wound up in the hands of weekend racers, and the program was soon dropped.

Professional drivers continued to achieve success with the GT 350, with the car winning its second straight Sports Car Club of America (SCCA) championship.