Description
The Ford Mustang Fastback GT with 271 horsepower was one of the most exciting versions of the original pony car, combining the sleek fastback 2+2 body style with the most powerful small-block V8 of the era, the 289 High Performance “K-code.” Introduced in 1965, this configuration represented the Mustang at its sportiest before the arrival of the big-block engines in 1967, offering buyers a genuine muscle car experience wrapped in one of the most stylish and versatile body styles of the time.
The fastback body was added to the Mustang lineup several months after the coupe and convertible, giving the car a more aggressive, European-inspired look. Its sloping roofline, distinctive rear quarter-panel louvers, and fold-down rear seat made it both practical and sporty. The GT package further distinguished the car with fog lamps integrated into the grille, GT badges, dual exhausts with chrome tips, and styled steel wheels. Side stripes and optional racing-inspired touches such as Rally-Pac gauges gave the GT fastback an unmistakable presence, especially when ordered in bold colors.
Inside, the GT fastback blended performance character with comfort. Standard bucket seats, a floor-mounted shifter, and a driver-focused dashboard gave it a sporting atmosphere, while the optional deluxe “Pony” interior added embossed seat designs, wood-grain accents, and upscale details. The fold-down rear seat unique to the fastback offered extra cargo space, making it more versatile than the coupe or convertible. Buyers could also equip their cars with features like air conditioning, AM/FM radios, power steering, and a tachometer, making the GT fastback either a stripped-back performance car or a stylish grand tourer.
The highlight of the car was its 289 cubic inch High Performance V8. Rated at 271 horsepower at 6,000 rpm, this K-code engine featured solid lifters, a hotter camshaft, a four-barrel carburetor, 10.5:1 compression, and heavy-duty internals, all designed for sustained high-rev performance. While Ford officially rated the engine conservatively, real-world figures often exceeded its advertised numbers. The 289 Hi-Po was paired most often with a four-speed manual gearbox, though a heavy-duty three-speed and automatic were also offered. Dual exhausts and a throaty exhaust note underscored the car’s performance intent.
On the road, the Mustang Fastback GT 271 HP was lively and engaging, with acceleration that could push it from 0–60 mph in under seven seconds and through the quarter-mile in the mid-15-second range. The GT package added front disc brakes, stiffer suspension, and improved steering, which gave the car better control and handling than non-GT Mustangs. While still not a precision sports car, the GT fastback had enough agility to satisfy enthusiasts, especially when compared to larger American muscle cars of the period.
Priced at around $2,700 when new, the GT 289 Hi-Po Fastback was not cheap, but it appealed to buyers who wanted more than just the Mustang’s fashionable looks. It offered a genuine performance upgrade while still being practical enough for everyday use. It also served as the foundation for Carroll Shelby’s GT350, which used the same fastback body and K-code engine as its base.
Today, the Ford Mustang Fastback GT with the 271-horsepower 289 is one of the most collectible and celebrated early Mustangs. Its combination of the iconic fastback styling, the rare and desirable Hi-Po engine, and the GT package makes it highly sought after by enthusiasts and collectors. Restored examples command premium values, as they represent one of the purest expressions of the Mustang’s original promise: style, performance, and versatility, all in one iconic package.