1957 Pontiac Bonneville Convertible

Semon 'Bunkie' Knudsen began working with the Pontiac Division of General Motors in 1939. He became general manager of the Detroit Diesel Division in 1955, a vice-president of the company and general manager of Pontiac Division in 1956. He was tasked with improving sales and improving the image. At the time, Pontiacs were viewed as reliable but had a stodgy image. With the help of Pete Estes from Oldsmobile and John DeLorean from Packard, they began work on creating high performance versions of Pontiac's existing models.

Knudsen re-worked the late pre-production 1957 model by removing its side trim and silver streaks. The first announcement of the Bonnevile was made on December 2nd of 1956, and Pontiac General Sales Manager Frank V. Bridge later announced it in a latter on January 11th of 1957. Each dealer was allowed one Bonneville, with production limited to 630 examples that model year. Power was from a 347 cubic-inch V8 with a cast-iron block and overhead valves. It was fitted with a Rochester mechanical fuel-injection setup and was given a 10.25:1 compression ratio. A factory horsepower rating for the Bonneville was never released by the factory, however it was estimated to produce 315 horsepower at 4,800 RPM.

This particular example has spent much of its life in Southern California and has its original body panels and trim. It is finished in ivory with red spears and a red and ivory leather-and-vinyl interior. Its factory options include power steering, power brakes, power windows, power seat, power antenna, Wonderbar radio with FM tuner, electric wipers, a retractable trunk light and a 3.64:1 Positraction axle. It was given a rotisserie restoration in 2004, during which the engine and Hydra-Matic transmission were rebuilt, the chrome was re-plated, the stainless-steel trim was polished and new glass and wiring were installed. A new Haartz cloth convertible top was fitted, along with a NOS trunk liner and a new brake system. After the work was completed, the car won the Gold Award at the Glenmoor Gathering in Canton Ohio, in 2004.

By Daniel Vaughan | Oct 2018