Photography: Dave Lundy, Dane Gingerelli, and courtesy of Pontiac Motor Division
n the last issue, we brought you the first installment of our Grand Prix history, which covered the model's introduction and evolution, through 1966. In our second installment, we look at the 1967-72 models, and see how the Grand Prix evolved along with the market it was intended to command.
1967 Since 1967 marked the first year without the legendary Tri-Power induction system, Grand Prix engine availability was simplified. In place of the triple 2-barrel system was a spread-bore Rochester Quadrajet 4-barrel carb. It was equal in performance to the Tri-Power and was simpler to tune and maintain.
The 1967 model year was significant for the Grand Prix—for a variety of reasons. The Grand Prix got a completely new look from the belt-line down, and, for the only time, a production convertible was offered. What's more, the engine lineup saw several changes as well.
While the 1967 again shared the same basic body as the Catalina, it looked significantly different. Up front, the Catalina's stacked headlight treatment was passed up for the Grand Prix. The GP and the Cat utilized the same front bumper, but when used on the GP, it housed both disappearing headlights and headlight doors with integral grille. In the place where the top headlight would have been was a louvered front fender extension panel.
The GP's taillight panel was unique, and housed slotted taillights that were similar to the ones on the '67 GTO and Firebird.
The 1967 Pontiac engine lineup highlighted some significant changes. Both the 389 and 421 engines received a bore increase to 4.12 inchesfor new displacements of 400 and 428 cubic inches, respectively. In addition, the venerable Pontiac block received new cylinder heads with completely redesigned ports. Valve diameters were increased to 2.11 inches for intakes and 1.77 inches for exhausts. To make room for the increased valve sizes, the distance between the valvestem centers was increased from 1.82 to 1.98 inches. The new heads were said to increase airflow from 30 to 35 percent and were superior to any previous designeven that of the Super Dutys.