The GTO was introduced in 1964 as a performance option for the Tempest in convertible, coupe and hardtop form. Standard equipment included 389 V8 which developed over 325 hp. Moreover, the package included a four-barrel carburetor, dual exhaust and premium tires. Available as options were 4-speed automatic or manual gearbox, limited slip differential, tachometer, seat belts, power steering and power brakes.

The hottest version of the GTO included a tri-power carburetion setup. Three vacuum powered Rochester carburetors increased the power to an astonishing 348 horsepower. In 1967 GM made a corporate ban on multi-carburetor engines. This put an end to the legendary tri-power GTO.

In total over 32 000 GTOs were sold in its first year. Largely helping sales was the low $300 price for the Tempest GTO. Quickly, the GTO became a major success, defining and motivating an upcoming market of muscle cars.