1965 Pontiac GTO
John Z. DeLorean’s workaround of GM’s corporate ban on engines larger than 330 cubic inches in intermediate-sized cars produced one of the decade’s most consequential performance vehicles.
By packaging a full-size 389 CI V-8 into the mid-size Tempest body as an option group, DeLorean effectively created the template for the American muscle car.
Legend holds that Pontiac had roughly 5,000 orders in hand before GM management fully grasped the car’s sales momentum.
For 1965, the GTO continued as an option on the Tempest LeMans hardtop, coupe, and convertible. The exterior wore vertically stacked headlights, simulated hood scoops, and GTO badging that set it apart from the standard Tempest.
The 389 was offered in two states of tune: a single four-barrel carburetor version rated at 335 horsepower, or the Tri-Power setup with three two-barrel carburetors producing 360 horsepower.
Both were available with either a three-speed manual, four-speed manual, or automatic transmission. Pontiac sold 75,352 GTOs for 1965, confirming that DeLorean’s gamble had paid off decisively.
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