"Iacocca had to fight hard to get the $75 million it would take to develop and build Mustang from (then-Chairman) Henry Ford II. That was chicken feed," Davis recalled. But after the embarrassing and financially devastating failure of Ford's Edsel just a couple of years before, the company was reluctant to take chances, he said.
Cash in hand, Ford's designers and engineers worked feverishly to pull the project together in barely two years, about half the time it normally took to develop a new car from the ground up. But the first production models were already in dealer showrooms in time for the World's Fair debut on April 17, 1964.
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In fact, the first Mustang had already been sold. Gail Wise was a newly graduated teacher from suburban Chicago who, at 22, was looking for something fun to drive. But nothing in the Ford showroom interested her, so the frustrated salesman let her peek under the covers, where a Mustang was waiting for official word that it could go on sale. Wise wouldn't wait, and she bought the "pony car" on the spot.
At a modest $2,368—about $18,000 today—it was a relative bargain, even though such commonplace features of today, such as air conditioning, power windows and even power brakes, cost extra. Nonetheless, Ford erred on the conservative side, planning to produce just 100,000 of that first model year.
It could barely keep up with demand, hitting that target within months on its way to selling 418,000 the first year. Along with the original plant near its headquarters in Dearborn, Mich., Ford quickly tooled up assembly lines in New Jersey and California to boost capacity.
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The car was so successful it engendered a new breed of sporty, American iron, a class quickly dubbed "pony cars." But how the new Ford became the Mustang remains a matter of debate. According to some recollections, it was originally meant to honor the legendary P-51 fighter plane of World War II, though Ford veteran Davis insists the car was always envisioned as a four-wheel take on a galloping horse.
Whatever the truth, Mustang is "a timeless statement," contends J Mays, the recently retired Ford design chief who had the 2015 pony car as one of his last major projects.
It certainly has stood the test of time. There are only a handful of nameplates still in existence that have been around for 50 years. In fact, you might have a finger or two left over.
Yet Mustang came close to losing its way several times. The original was followed in 1974 by the unloved Mustang II. And following the twin oil shocks of that era, as automakers walked away from V8s in favor of more fuel-efficient—if boring—6s and 4s, the era of the pony car seemed over.
But, by the mid-1980s, the V8-powered Mustang GT was back. And today, there are more powerful versions than ever, with the Shelby GT500 edition nudging near to 700 horsepower. Even the "base" 6-cylinder 2015 Mustang will deliver more than 300 horsepower—nearly twice the output of the original—yet it will also offer more than 30 mpg, according to the EPA estimate.
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The launch of the all-new 2015 Mustang—and all the attendant publicity drummed up by the Ford marketing machine—couldn't come along at a better time. The outgoing version of the pony car has lost momentum in recent years and last year slipped behind its longtime rival, General Motors' Chevrolet Camaro.
And Chevy isn't about to step out of the picture as Ford's Golden Anniversary celebration hits its peak. The Camaro recently went through its own major update, and a super-high-performance version will share the limelight at this week's New York Auto Show.
"For five decades, the Camaro and the Mustang have been battling it out in every possible setting," said Mark Reuss, GM's executive vice president of global product development, purchasing and supply chain. "These two cars have been striving to beat each other on the track, on the drag strip and on the streets. That competition is a big part of why both cars are so amazing, and so popular, today."
Whether Mustang will regain its position as pony car king-of-the-hill remains to be seen. But both Ford and Chevy hope that all the attention will drum up interest from a new generation of fans.
is a freelancer for CNBC. His travel and accommodations for this article were paid by an automaker.