Halfway through the 1963 model year, Ford gave the Galaxie a bold new roof to align with the company’s ambitious Total Performance program, and buyers snapped it up.

Above, here’s what the Galaxie two-door hardtop looked like when the ’63 Fords were introduced in Autumn of 1962. Its starchy, squared-off roofline and thick C-pillar were borrowed directly from the  Thunderbird, Ford division’s luxury flagship. In fact, the Galaxie’s ad copy called it a “Thunderbird roof,” and the two cars were photographed together to make sure everyone got the message.

It was a clean, classic look, but it was completely out of step with the company’s emerging Total Performance campaign. At the behest of Henry Ford II himself, the automaker was now wading into every form of motorsports: NASCAR, Indy cars, and drag racing. If the ambitious Total Performance program was to fulfill its ultimate mission of selling cars, Ford’s production models would have to at least look the part.

Ford stylists flipped the script at mid-season when the automaker launched its “1963 ½” models. (Ford had begun its ” ½ ” promotions the previous year, though midyear rollouts were nothing new in the Motor City.) From the beltline down the styling was unchanged, but with a redesigned roof and greenouse the Galaxie was transformed. This new body style was officially called the Sports Hardtop, but on the streets and racetracks it quickly became known as simply the fastback.

The new roofline was lower, with a thin C-pillar that swept to the rear at a dramatically shallow angle. To further emphasize the convertible look an optional vinyl top was available, and it included a strip of bright metal trim across the rear to simulate an exposed top bow. Yes, the new fastback look was an undeniable success. In spite of its mid-1963 introduction, the Sports Hardtop outsold the boxtop by a two-to-one margin, and in 1964 the formal two-door hardtop was discontinued.

The more aerodynamic shape was a welcome change for Ford racers in NASCAR, who had struggled with the ’62-’63 boxtop and its excessive drag and lift. (See our feature here.) But oddly enough, racing played no role in the ’63 ½ roof design. At the time, Ford’s production-car styling and racing programs ran on different tracks with no communication.

According to Ford studio chief Joe Oros, the two developments were in no way related. The fastback, he asserted, “was not influenced by racing.” Rather, he noted, the only goal was to give the hardtop “a youthful, sporty verve, and the fastback was one way to do it.” For once, form and function came together.