Pontiac's Tempest went through a major transition in 1964. No longer a shirttail relative of the Chevrolet Corvair, it was fattened up and marketed as a family car. The "sporty" LeMans model featured standard bucket seats and unique trim moldings, but had the same engine combinations as all other Tempests.
To enhance their image, the product development folks at Pontiac Motor Division wanted to install the 389-c.i. V8 from their full-size cars into the LeMans. However, GM had a corporate edict that imposed a maximum engine size for a car of no more than one cubic inch for every ten pounds of weight. The heaviest Tempest crossed the scales at 3,260 pounds, so the 326-c.i. V8 was the largest allowed.
To sidestep this, Pontiac's engineers simply let the corporate brass approve the LeMans with the 326 engine in the fall of 1963. Since approval was only required on new models, the 389 engine was added as a $295 option package shortly after introduction, and named the GTO. Besides the 389 engine, it added special exterior and interior badging, simulated engine-turned dashboard and glovebox facings, and simulated hood air vents. Thus the age of the muscle car was born.
The 389 GTO used high-compression heads from Pontiac's 421 HO engine, and was fed by either a single four-barrel carburetor (325 horsepower) or triple two-barrel induction (348 horsepower). While a three-on-the-tree manual transmission was standard, four-speeds and the Hydra-Matic were popular options.
The car turned 15-second quarter-mile runs at 91 miles per hour, and had an alleged top speed of 122 miles per hour. Even with substandard brakes, the GTO's high power-to-weight ratio and affordable price gave it widespread appeal. In 1964 32,450 of all body styles were sold.
The majority were driven hard when new, and have not often had pampered lives since. Cars with any type of story or numbers mismatch to them, while possibly making interesting drivers, should in no way be looked upon as a safe investment. Verifiable original cars, on the other hand, have nowhere to go in value except up. GTOs are a cultural icon for the early '60s (helped in no small part by Pontiac's own PR department), and convertibles have recently sold at auction for as much as $35,000.
A word of warning, though. Created almost as a covert operation, the 1964 GTO is not difficult to fake. If there has ever been a car that exemplifies the saying "there are more red convertibles in existence now than were originally built," it's the GTO. All the GTO-specific trim pieces are readily available from aftermarket catalogs, so someone with a GTO-specification block (1964-66 was one of the few times that Pontiac didn't serialize their engines), heads and an eight-cylinder LeMans body could build a very convincing fakey-doo.