I had turned all of seven years when my father gifted me the book “Motor Car, An Illustrated International History” by DB Wise. Chapter 15, aptly named “The Flamboyant Fifties” had a picture of a silver grey Mercedes Coupe in profile on page 276. It had a slippery shape and wheels which covered nearly half the height of the car. There were eyebrow like structures on the wheel arches and only “half height” doors. Remember, I was a kid growing up in India in the seventies and seeing a real Mercedes on roads was as rare as seeing a panther prowling on the roads. Interestingly, elephants were more common. There was no internet, so I never knew that the doors were actually gull-wings. I came to know about if after a few years when I laid my hands on a book covering exclusively the history of Mercedes.
Notwithstanding, it was kind of love at first sight and the second 1:18 scale model that I bought was a, well, silver Mercedes 300 SL. It occupies a place of pride in my collection and once I started to understand the technology behind the car, I was even more enamoured by it. This car was developed from a racing sports cars from 1952, the Mercedes SL. The American importer of Mercedes, Max Hoffman was able to convince the board of Mercedes about the market for a light and fast sports car in USA. Mercedes took the gamble and introduced the Mercedes Benz 300 SL in 1954 during the International Motor Sports Show at New York. This was departure for Mercedes as all their new launches till then had been at either Frankfurt or Geneva. However, the gamble paid off and 80% of the cars ever produced were sold in the USA.
The chassis of the 300 SL was unique and had been lifted directly off the SL. It was an Aluminium tube space frame designed by Rudolph Uhlenhaut. It provided high level of strength while weihging a mere 50 Kgs (110.23lbs). However, as the space frame completely enveloped the passenger compartment, conventional doors could not be fitted. To over come this problem, the company introduced doors hinged at the roof and which lifted up to allow ingress and egress. These doors, called the gull-wings became the trademark of the 300 SL. Though the body was made of steel, weight was further reduced by the use of Aluminium in the hood, doors and boot. A very expensive option of having the complete outer skin also in Aluminium was available but was exercised by just 29 people.
The 300 SL was fitted with an engine which owed its origins to the DB 601 V-12 engines which powered nothing less than the Messerschmitt Bf 109E fighter aircraft of the Luftwaffe. This engine was the first in the world to have direct fuel injection. The mechanical fuel injectors were developed by Bosch and helped bump the power output by more than 25% over the – hold your breath – race car on which this car was based. Aerodynamics played an important role in the performance of the car and the eyebrows over the wheel arches were not for decoration but improved the airflow and reduced drag. The front suspension comprise double wishbones, coiled springs and stabilising bar. The rear had high pivot swing arm axle, radius arms and coil springs.
The 300 SL was powered by a 2,996 cc (183 Cu-inch) inline six cylinder naturally aspirated petrol engine. It breathed through two valves per cylinder and got the energy drink (petrol) through a mechanical fuel injection system. This engine could generate 212 BHP at 5,800 rpm. It churned out a torque of 275 N-m (203 ft-lb) at 4,600 rpm. All this power and torque was transmitted to the rear wheels through a four speed manual gearbox.
This engine could push the 4,520 mm (178″) long, 1,790 mm (70.5″) wide and 1,300 mm (51.2″) tall car weighing 1,515 Kg (3,340 lbs) to a top speed of between 235 km/h ( 146 mph) and 260 km/h (162 mph) depending on the final ratio opted for. It could accelerate from 0 to 100 km/h in 7.4 seconds (0-60 mph in 7.1 seconds). A quarter mile was disposed off in 15.5 seconds achieving a speed of 151 km/h (94 mph) when you started braking. The brakes were 260 mm (10.23″) power assisted drums.
The beautiful Mercedes AMG SLS is considered as the spiritual descendant of the 300 SL.
The Transport Journal 