The Mercedes 300 SL got gullwing doors because ordinary ones would not fit
The famous upward-swinging doors of the Mercedes-Benz 300 SL were not a styling gimmick. Its lightweight tubular frame ran so high along the cabin that the top tube sat level with the driver's elbow. Conventional hinged doors were impossible, so engineers hinged them from the roof instead.
The car grew out of the W194 endurance racer of 1951, whose 175-horsepower engine was weaker than Ferrari's and Jaguar's but whose light weight and low drag made it a winner, including at Le Mans and the Carrera Panamericana in 1952. American importer Max Hoffman saw a market among wealthy US enthusiasts and, at a 1953 meeting in Stuttgart, placed an order for 1,000 cars to guarantee the run. The road car accordingly debuted at the New York auto show in February 1954 rather than in Frankfurt or Geneva.
Engineering set it apart. Chief engineer Rudolf Uhlenhaut designed a frame of thin chrome-molybdenum tubes arranged in triangles, weighing just 82 kg yet very stiff. The three-litre straight six was tilted 50 degrees to sit low, and it was among the first car engines with mechanical direct fuel injection, raising output to 240 horsepower. With the tallest gearing, the coupé reached up to 263 km/h, making it the fastest production car of its day. Aluminium bonnet, doors and boot lid saved more weight; only 29 all-aluminium bodies were built. Even the brows over the wheel arches had a job, deflecting road spray from the windscreen.
Living with it took effort. The high sill made climbing in awkward, so the steering wheel tilted 90 degrees out of the way. Luggage rode behind the seats because the boot held the spare wheel and fuel tank. The injection pump kept spraying fuel briefly after shutdown, thinning the oil, so owners were told to change it every 1,000 miles.
The coupé was built from 1954 to 1957, followed by a roadster until 1963. For decades nobody agreed what SL stood for, until a chance archive discovery in 2017 settled on Super Leicht, super light.
Source: Mercedes-Benz 300 SL
