Most of Pontiac’s models built during the 1960s and 1970s were either styled like, or were siblings to, other GM makes (except Cadillac). However, Pontiac retained its own front and rear end styling, interiors, and engines.
1964 Pontiac Bonneville Brougham
Full size Pontiacs from 1960 to 1968 featured these unique, finned, 8 bolt rims, which aided in the cooling of the drum brakes
The 1961 models were similarly reworked. The split grille returned, as well as all-new bodies and a new design of a perimeter-frame chassis for all its full-size models (something which would be adopted for all of GM’s intermediate-sized cars in 1964, and all its full-sized cars in 1965). These new chassis allowed for reduced weight and smaller body sizes. It is interesting to note that the similarly styled Chevrolet still used the radically different “X” frame in the early 1960s.
But a complete departure in 1961 was the new Tempest, one of the three BOP (Buick-Olds-Pontiac) “compacts” introduced that year, the others being the Buick Special and Skylark and Oldsmobile F-85 and Cutlass. Toward the end of the 1961 model year an upscale version of the Tempest called the “LeMans” was introduced, named after the famous 24 Hours of Le Mans auto race in France.
All three were uni-body cars, dubbed the “Y-body” platform, combining the frame and body into a single construction, making them comparatively lighter and smaller. All three put into production new technology pushed by John DeLorean which GM had been working on for several years prior, but the Tempest was by far the most radical. A flexible steel shaft rotating at the speed of the engine delivered power from the front-mounted engine through a “torque tube” to a rear-mounted trans-axle. This innovation not only delivered close to a 50/50 front-rear weight distribution that drastically improved handling, it enabled four-wheel independent suspension which enhanced it even more. It also all but eliminated the large floor “hump” common to front-engined rear-drive cars.
Though the Tempest’s transaxle was similar to the one in the Corvair, introduced the year before, it shared virtually no common parts. GM had planned to launch a Pontiac version of the Corvair (dubbed “Polaris”), but “Bunkie” Knudsen—whose niece had been seriously injured in a Corvair crash—successfully argued against the idea. The Polaris design apparently made it to full-scale clay before it was cancelled. Instead, DeLorean’s “rope-shaft” design was green-lighted.
Contemporary rumors of the rope-shaft’s demise due to reliability problems are unfounded; the rope-shaft’s durability and performance had been proven in tests in full-size Pontiacs and Cadillacs in 1959, and only adapted to a smaller car in 1960. The Tempest won the Motor Trend “Car of the Year” award in 1961—for Pontiac, the second time in three years. DeLorean’s vision has been further vindicated by the adoption of similar designs in a slew of modern high-performance cars, including the Porsche 928, 924, and 944, the Corvette C5, and the Aston Martin DB9.
Unless customers checked an option, the Tempest’s power-plant was a 194.5 Ci inline-slant-four-cylinder motor, derived from the right bank of the venerable Pontiac 389 V8, enabling it to be run down the same production line as the 389, saving costs for both the car’s customers and Pontiac. Pontiac engineers ran early tests of this motor by literally cutting off the left bank of pistons and adding counterweights to the crankshaft, and were surprised to find it easily maintained the heaviest Pontiacs at over 90 miles per hour (140 km/h). In production, the engine received a crankshaft designed for just four cylinders, but this didn’t completely solve its balance issues. The engine gained the nickname “Hay Baler” because of it tendency to kick violently, like the farm machine, when its timing was off.
The aforementioned Buick 215 V8, was ordered by less than two percent of its customers in the two years it was available, 1961 and 1962. Today, the 215 cars are among the most sought-after of all Tempests. In 1963, Pontiac replaced the 215 with a “new” 326 which was really a 336 with a bore of 3.78 and stroke of 3.75 ( same stroke as the 389 ), an iron block mill that had the same external dimensions and shared parts with the 389, but an altered, reduced bore. The car’s body and suspension was also changed to be lower, longer and wider. The response was that more than half of the 1963 Tempests and LeMans (separate lines for that one year only) were ordered with the V8, a trend that did not go unnoticed by management. The next year, the 326 would become a true 326 with a new bore size of 3.72. The Tempest’s popularity helped move Pontiac into third place among American car brands in 1962, a position Pontiac would hold through 1970. The Buick 215 V8 would remain in production for more than thirty five years, being used by Britain’s Rover Group after it had bought the rights to it. GM attempted to buy the rights back, however, Rover wished, instead, to sell the engines directly.
Source : https://en.wikipedia.org/wiki/Pontiac