1957 BMW 503

The BMW 503 and 507 models would return prestige and notoriety to the German automaker but at a tremendous financial cost. Produced from May 1956 to March 1959 and considered BMW's first postwar sport coupe, a total of 413 examples of the 503 were built, with 139 of those being Cabriolets.

The BMW 503 was launched at the 1955 Frankfurt Motor Show, the same as the introduction of the BMW 507 TS. Designed by Albrecht von Goertz, it was more conventionally styled than the 507 and was offered as both a 2+2 convertible and coupe body style. The lightweight 3.2-liter V8 engine was sourced from its 502 predecessor and delivered up to 140 horsepower.

With over 400 examples of the 503 sold, it was far more popular than the 507 Roadster, which found 253 buyers. Both cars were expensive, with the 503 being higher at DM29,500 compared to DM26,500 for the 507 roadster. The issue with the 507 Roadster was its lackluster performance.

The Genesis
The 503 was championed by Hanns Grewenig, sales manager of BMW, who was convinced a sports car based on the company's 501 and 502 luxury cars would find favor within the marketplace. When chief engineer Fritz Feidler suggested a smaller model (to be called the 331), perhaps similar to the very successful pre-war 328, his idea was rejected by Grewenig on the belief that BMW did not have the capability to manufacture in quantity. Additionally, he felt BMW needed a new and modern luxury car that could achieve a higher profit margin per unit. When company management witnessed the public reception and reaction to the Mercedes-Benz 300 SL in New York in February 1954, they agreed with Grewenig.

The Design
Austrian-born entrepreneur Max Hoffman, at that time the US importer of various European makes, suggested to industrial designer Albrecht von Goertz that he should submit design proposals to BMW for the 503 and 507. Count Albrecht von Goertz had designed everything from fountain pens to furniture and had worked for Raymond Loewy on the trend-setting Studebakers. Up to this point in history, Goertz had never before styled an entire car. He penned two different designs - a coupe and a cabriolet - both of which debuted in prototype form at the 1955 Frankfurt Auto Show.

Mechanical Specification
The sleek and modernistic 503 retained the 502's chassis dimensions, suspension, and centrally mounted gearbox. The 502 had been based upon BMW's first postwar automobile model, the 'Baroque Angel' 501, and debuted the company's new V-8 engine for 1954. Engineer Fritz Fiedler created two versions of a new ladder frame, one with the same 111.6-inch wheelbase as the 502 and another that was shorter. The 503 had a length of 187 inches, a width of 67 inches, and a height of 57 inches. It was slightly longer than the 186-inch length of the 502 but slimmer in width (by 3 inches) and lower in height (by 3 inches). Both of the ladder frames created by Fiedler used the front suspension from the 502 (the 503 also used the 502's rear suspension), its steering system, and braking system. Sixteen-inch wheels were located at all four corners.

The perimeter chassis was constructed of sheet steel, along with some of the body bracing, inner wings, and bulkhead. Aluminum/magnesium alloy was used for the doors, bodywork, trunklid, and hood (bonnet). The prototypes were formed from aluminum. The entire dashboard assembly was formed from cast aluminum.

The four-speed manual transmission had a standard final drive ratio of 3.90:1 or could be optioned with a 3.42:1 ratio.

The 3.2-liter V8 engine had a chain-drive oil pump, a 7.5:1 compression ratio, a pair of carburetors, and produced 140 horsepower at 4,800 RPM. The 503s destined for the U.K. were tuned to 507 specifications, either by BMW or by AFN Ltd (the BMW Concessionaires for the UK). In this configuration, the engine offered 150 horsepower.

The 503 was every inch the Grand Routier, with 2+2 seating, generous luggage space, and a long and imposing bonnet. The cabriolet version was the first European convertible to be equipped with an electro-hydraulic hood and windows.

Changes
In February 1957, the side vents on the dashboard were replaced by a plate welded in place.

The Mark II version was introduced in September 1957 and brought with it minor updates to the interior and exterior styling, and minor revisions to the drivetrain. The ashtray was relocated from beneath the dash to adjacent to the speaker grille. The previous chrome trim strip that kicked up at an angle along the side now remained straight at the rear. The gearbox was bolted to the engine, and the gear lever was now located on the floor (previously on the steering column). All of the right-hand drive cars had floor-mounted gear levers. Only three right-hand drive cabriolets were handmade for the British market.

Demise
The BMW 503 asked too much and offered too little. Its price was twice the cost that Hoffman had anticipated, and he quickly canceled his arrangement with BMW. This left BMW without dealership or servicing arrangements in the United States. In Europe, the 503 found favor with the social elite, film stars, nobility, and Heads of State.

Production of the 503 ceased in March 1959, and it was replaced by the Bertone-bodied BMW 3200 CS in 1962.

by Daniel Vaughan | Jun 2024