First conceived by Ford product manager Donald N. Frey and championed by Ford Division general manager Lee Iacocca, the Mustang prototype was a two-seat, mid-engine roadster. This would later be remodeled as a four-seat car penned by David Ash and John Oros in Ford's Lincoln–Mercury Division design studios, which produced the winning design in an intramural design contest called by Iacocca. To cut down the development cost, the Mustang was based heavily on familiar, yet simple components. Much of the chassis, suspension, and drivetrain components were derived from the Ford Falcon and Fairlane. The car had a unitized platform-type frame, which was taken from the 1964 Falcon, and welded box-section side rails, including five welded crossmembers. Although hardtop Mustangs were the majority of the sales, durability problems with the new frame led to the unusual step of engineering the (necessarily less rigid) convertible first, which ensured adequate stiffness.
Overall length of the Mustang and Falcon was identical, although the Mustang's wheelbase was slightly shorter. With an overall width of 68.2 in (1732 mm), it was 2.4 in (61 mm) narrower, yet the wheel track was nearly identical. Shipping weight, about 2570 lb (1170 kg) with the six-cylinder engine, was also similar. A fully-equipped V8 model weighed about 3000 lb (1360 kg). Though most of the mechanical parts were taken directly from the Falcon, the Mustang's body shell was completely different; sporting a shorter wheelbase, wider track, lower seating position, and overall height. An industry first, the "torque box" was an innovative structural system that greatly stiffened the Mustang's construction and helped contribute to better handling.
1964–1966
1966 Ford Mustang coupe
Since it was introduced five months before the normal start of the production year, this first model has become widely known, although incorrectly, as the 1964 1/2 model. A more accurate description is the "early 1965" model, as the car underwent several significant changes at the start of the regular model year. All the early cars, however, were touted as 1965 models. The base model hardtop with its 170 in³ straight-6 engine and three-speed manual transmission listed for US$2,368.
Some minor changes to the Mustang occurred at the start of the normal 1965 model year production, five months after its introduction. These cars are known as "late 65's," and were built from April through September. First, there was an almost complete change to the engine lineup. The I6 engine made way for a new 200 in³ version that produced 120 hp (89 kW). Production of the 260 in³ engine ceased with the traditional end of the 1964 model year. It was replaced with a new 200 hp (150 kW) 289 in³ engine with a two-barrel carburetor as the base V8. A 225 hp (168 kW) four-barrel carbureted version was next in line, followed by the unchanged "Hi-Po" 271 hp (202 kW) 289. The DC electrical generator was replaced by a new AC alternator on all Fords (the quickest way to distinguish a 1964 1/2 from a 1965 is to see if the alternator light on the dash says "GEN" or "ALT"). The now-famous Mustang GT was introduced as the "GT Equipment Package" and included a V8 engine (most often the 225 hp (168 kW) 289), grille-mounted fog lamps, rocker panel stripes, and disc brakes. A four-barrel carbureted engine was now available with any body style. Additionally, reverse lights were an option added to the car in 1965. The Mustang was originally available as either a hardtop or convertible, but during the car's early design phases a fastback model was strongly considered. The Mustang 2+2 fastback made its inaugural debut with its swept-back rear glass and distinctive ventilation louvers.
The standard interior features of the 1965 Mustang included adjustable driver and passenger bucket seats, an AM radio, and a floor mounted shifter in a variety of color options. Throughout the 1965 model year, Ford continued to add to the Mustang's interior options. The Interior Decor Group was popularly known as "Pony Interior" due to the addition of embossed running ponies on the seat fronts, and also included integral armrests, woodgrain appliqué accents, and a round gauge cluster that would replace the standard Ford Falcon instrumentation. Also available were sun visors, a (mechanical) remote-operated mirror, a floor console, and a bench seat. Ford would later offer an under-dash air-conditioning unit, and discontinue the vinyl with cloth insert seat option, offered only in early 1965 models.
The 1966 Mustang debuted with moderate trim changes including a new grille, side ornamentation, wheel covers, and gas cap. Additionally, an automatic transmission for the "Hi-Po," a large number of new paint and interior color options, an AM/eight-track sound system, and one of the first AM/FM monaural automobile radios were offered. The 1966 Mustang did away with the Falcon instrument cluster and made the previously option-only round gauges and padded sun visors standard equipment.
Although similar in design, the 1965 and 1966 Mustangs have a few visual exterior clues that differeniate the two model years. Among the differences is the emblem on the quarter-panels behind the doors. In 1965 the emblem is a single vertical piece of chrome, while in 1966 the emblem was smaller in height and had three horizontal bars extending from the design, resembling an "E". The front intake grilles and ornaments were also different. The 1965 front grille used a "honeycomb" pattern, while the 1966 version was a "slotted" style. While both model years used the "Horse and Corral" emblem on the grille, the '65 had four bars extending from each side of the corral, while on the '66, these bars were removed.
It is always easy to mix up the Mustangs ranging from first production to the 66 model. The 1964 [tech. 1964 1/2] and 65 Mustang included the trademark "honeycomb" pattern grill. As the 66 sustained the straight line. That makes it a clear detection.
1967–1968
1968 Ford Mustang GT C/S
The 1967 model year would see the first of the Mustang's many major redesigns with the installation of big-block V8 engines in mind. The overall size was increased, as was the cargo space. Exterior trim changes included concave taillights, side scoop (1967) and chrome (1968) side ornamentation, square rear-view mirrors, along with the usual yearly wheel and gas cap changes. The high-performance 289 option now took a supporting role on the option sheet behind a massive 320 hp (239 kW) 390 in³ (6.4 L) engine direct from the Thunderbird, which was equipped with a four-barrel carburetor. Stock 390 with 4-speed manual Mustangs of the day were recording quarter mile times of mid 13-seconds, with trap speeds of over 105 mph (168 km). A drag racer for the street took a stand during the middle of the 1968 model year, as the 428 in³ (7.0 L) Cobra Jet engine officially rated at 335 hp (250 kW).
The interior was more spacious due to an increase in the overall size of the vehicle. 1967-68 did away with the "Pony Interior" in favor of a new deluxe interior package, which included special color options, brushed stainless steel (1967) or woodgrain (1968) trim, seat buttons, a tilt steering wheel, and special interior paneling. The air-conditioning option was fully integrated into the dash, the speakers and stereo were upgraded, and unique center and overhead consoles were options. The fastback version had a fold down seat, and the convertible was available with folding glass windows.
The 1968 Mustang fastback gained pop culture status when it was used to great effect in the crime thriller Bullitt. Lt. Frank Bullitt drove a modified Mustang GT-390 fastback, played by legendary actor Steve McQueen, chasing two hitmen in a Dodge Charger in the film's famous car chase through the streets of San Francisco.
The California Special Mustang, or GT/CS, was visually based on the Shelby and was sold only in the Western states. Its sister, the High Country Special was sold in Denver. While the GT/CS was only available in coupe form, the High Country Special was available in a fastback and convertible version in 1967 and only as a coupe in 1968.
The industry reacts
In the Mustang's first two years of production, three Ford Motor Company plants in Milpitas, California; Dearborn, Michigan; and Metuchen, New Jersey produced nearly 1.5 million Mustangs. It was a tremendous success that left General Motors utterly unprepared and the Chrysler Corporation only slightly less so. Chrysler had just introduced the Plymouth Barracuda a few weeks before, and though the "'Cuda" would grow into one of the most revered muscle cars of all time, it started out at as just a Plymouth Valiant with a hastily grafted fastback rear window.
As for GM, they were certain that they had a Mustang fighter in the rear-engine Corvair Monza, but sales figures didn't even come close. The Monza was a fine performer, but it lacked a V8 engine and its reputation had been tarnished by Ralph Nader. It took GM until the 1967 model year to counter with the Chevrolet Camaro and Pontiac Firebird. Even Lincoln-Mercury joined the fray in 1967 with the introduction of an "upmarket Mustang" (and subsequent Motor Trend Car of the Year), the Mercury Cougar. The Cougar name had originally been given to the Mustang during the development phase. In 1968, American Motors (AMC) would introduce the Javelin and later, the 2-seat high-performance AMX. This genre of small, sporty, and often powerful automobiles was unofficially dubbed the "pony car" as a tribute to the car that started it all.
1969–1970
1969 Ford Mustang Mach 1 Special Edition
1969 saw the introduction of the car's third body style. The 1969 model featured a 302 in³ V8 rated at 220 hp (164 kW). The coupe was longer than previous models and sported convex rather than concave side panels. The model year featured some exceptional special editions including the Boss 302 Mustang, the Boss 429, and the new Mach 1, with a variety of new powerplants.
1971–1973
1972 Ford Mustang Mach 1
The Mustang grew larger and heavier with each passing year, culminating with the 1971 to 1973 models designed under the supervision of Ford's new product design manager, Semon "Bunkie" Knudsen, originally of General Motors. Knudsen's turn at the helm would see the last high-performance big-block Mustang, 1971's 375 hp (280 kW) 429 Super Cobra Jet. Ford originally planned to install a 460 in the Mustang as well. Unfortunately, that very same body style that was designed for the sole purpose of big-block installation versions was limited to a maximum of 351 in³ (5.8 L) in 1972 and 1973 due to extremely strict U.S. emission control regulations and low demand for big block muscle cars because of high insurance premiums. Two more high-performance engines were introduced in 1972; the 351 "HO" and the 351 Cobra Jet. Both cars were excellent performers, but nowhere near the level of the Boss cars and original Cobra Jet. Car companies switched from "gross" to "net" power and torque ratings in 1972, which coincided with manufacturers making low-compression motors with different, far more restrictive induction systems. Thus, making it difficult to compare power and torque ratings.
Very much a different car than the original 1964 model, Ford was deluged with mail from fans of the original car who demanded that the Mustang be returned to its original size and concept. Upon taking over the presidency of Ford Motor Company in December, 1970, Lee Iacocca ordered the development of a smaller Mustang for 1974 introduction with initial plans calling for the downsized Mustang to be based on the compact Ford Maverick, which was similar in size and power to the Falcon upon which the original Mustang had been based. Those plans were later scrapped in favor of an even smaller Mustang based on the subcompact Ford Pinto in order to better compete with the hot-selling sporty import coupes such as the Toyota Celica and Ford Capri, then built by Ford of Germany and Britain, with the German Capri sold in the U.S. through Lincoln-Mercury dealers as a "captive import" starting in 1970.
A red Mustang Mach 1 appears in the main car chase sequence of the 1971 James Bond film Diamonds Are Forever, where it is pursued by police cars along the Las Vegas Strip. The most memorable scene is when Bond tilts the car onto two wheels to drive it along a narrow alleyway. A black on yellow fastback, dubbed "Eleanor", is the star of the climactic 40-minute car chase in the 1974 cult hit Gone in 60 Seconds.