The 1964 Pontiac GTO is widely credited with launching the American muscle car era, combining midsize practicality with big-engine performance in a way that reshaped the industry. Introduced as an option package on the Pontiac Tempest LeMans, the GTO featured a 389 cubic-inch V8 that produced up to 348 horsepower with the Tri-Power three-carburetor setup, along with upgraded suspension, dual exhaust, and distinctive badging. At a time when GM discouraged large engines in smaller cars, Pontiac engineers quietly created a performance icon that appealed to younger buyers looking for speed and style without the price of a full-size performance model. Available as a hardtop coupe, convertible, or sport coupe, the 1964 GTO balanced aggressive performance with everyday usability, helping it sell far beyond expectations and paving the way for the muscle car boom that followed throughout the 1960s.