We talked about the sporty car for most of that afternoon, setting parameters for what it should look like — and what it should not look like — by making lists on a large pad, a technique I adapted from the management seminar.

We also had photographs of all the previous sporty cars that had been done in the Corporate Advanced studio as a guide to themes or ideas that were tired or not acceptable to management.

[14]Gale Halderman, in a 2002 interview with Collectible Automobile, spoke of the Mustang's evolution through the Ford design studio: Dave Ash had started a clay model of the car.

Although hardtop Mustangs accounted for the highest sales, durability problems with the new frame led to the engineering of a convertible first, which ensured adequate stiffness.

Gale Haldeman spoke of the engineering and design of the car in his interview, stating: No one knew the Mustang was going to be as popular as it was, but it created a huge stir in the company.

That was totally unusual, so we suspected the Mustang was going to be a hit.The idea for a fastback originated with Joe Oros as well and was designed in Charlie Phaneuf's studio.

[7] Since it was introduced four months before the usual start of the 1965 production year and manufactured alongside 1964 Ford Falcons and 1964 Mercury Comets, the earliest Mustangs are widely referred to as the "1964½" model by enthusiasts.

[10] Standard equipment for the early 1965 Mustangs included black front seat belts, a glove box light, and a padded dashboard.

Mustang Serial Number One (5F08F100001 from the pre-production batch) was sold on April 14, 1964, at the George Parsons Ford dealership in St. John's, Newfoundland, Canada.

The V8 models were identified with a badge on the front fender that spelled out the engine's cubic inch displacement ("260" or "289") over a wide "V." This emblem was identical to the one on the 1964 Fairlane.

[33] Fuel economy for the base V8 was good for the period, with a test by Popular Mechanics rating the optional 260 cubic inch engine with automatic transmission achieving 20.93 mpg‑US (11.24 L/100 km; 25.14 mpg‑imp) at a steady 60 mph (97 km/h).

The long-duration solid-lifter camshaft that allowed the high-revving 289's horsepower rating, was not a good match for a low stall speed automatic torque converter.

The "HiPo" could be identified by the 1-inch-thick (25 mm) vibration damper, (compared to 1/2 inch on the 225-hp version) and the absence of a vacuum advance unit on the dual point distributor.

The 1966 model year cars discontinued the Falcon instrument cluster, while the previously optional round gauges and padded sun visors became standard equipment.

[37] In 1965, Harry Ferguson Research purchased three Mustang hardtops and converted them to 4x4 in an attempt to sell potential clients on their FF AWD system.

Ford's designers began drawing up a larger version even as the original was achieving sales success, and while "Iacocca later complained about the Mustang's growth, he did oversee the redesign for 1967.

The high-performance 289 option was placed behind the newer 335 hp (250 kW; 340 PS) 390 cu in (6.4 L) FE engine from the Ford Thunderbird, which was equipped with a four-barrel carburetor.

During the mid-1968 model year, a drag racer for the street could be ordered with the optional 428 cu in (7.0 L) Cobra Jet engine which was officially rated at 335 hp (250 kW; 340 PS) all of these Mustangs were issued R codes on their VINs.

Other changes included front and rear side markers, "FORD" lettering removed from the hood, rearview mirror moved from frame to windshield, a 302 cu in (4.9 L) V8 engine option, and C-Stripe graphics were added.

Distinctive reflective striping was placed along the body sides, with a pop-open gas cap, dual exhausts, matte-black hood with simulated air scoop, and NASCAR-style cable with pin tie-downs.

It came with a six-cylinder engine (250 cu in (4.1 L)), a high stall torque converter for the standard automatic transmission, and a low, 2.33:1 rear axle ratio.

[69] The custom styling included a fiberglass front end with a combination loop bumper/grille that increased the car's overall length by 3 inches (76 mm), as well as five air intakes on the hood.

Again, the revised model grew in size, gaining 3 inches in width to accommodate Ford's big block 429 cu in (7.0 L) V8 without need for an extensive suspension redesign.

An additional edition, the Spring Special, was available between March and May 1971,[76] which added Mach 1 styling cues (side stripes, tu-tone paint, urethane bumper, honeycomb grill with sport lamps) to the hardtop.

Due to tightening emissions regulations, the Boss 351 edition and optional 429 big block were dropped after 1971,[82] leaving the 351 cu in (5.8 L) variants as the largest available engines for 1972 (and 1973).

Exterior differences were virtually unchanged, though all 1972 models were revised with "Fasten Seat Belt" warning lamps on the right side dash panel.

[83] Sprint editions were available in Hardtop and Sportsroof variants and featured white paint schemes with light blue accents and USA shield decals on the rear quarter panels.

An additional 50 Sprint convertibles were produced exclusively for the 1972 National Cherry Blossom Parade in Washington D.C.[84][85] 1972 saw the end of the special Ford muscle car performance engine era.

[102] In the first two years of production, three Ford Motor Company plants in Milpitas, California; Dearborn, Michigan; and Metuchen, New Jersey produced almost 1.3 million Mustangs.

Unprepared General Motors executives thought the rear-engined Chevrolet Corvair Monza would compete against the Mustang, but it also sold poorly by comparison.