The Mercedes 500K (type W29) is a sports car built by Mercedes-Benz between 1934 and 1936, and first exhibited at the 1934 Berlin Motor Show. It carried the factory designation W29. Distinguished from the 500 sedan by the "K" in its name which denoted the kompressor (supercharger) only fitted to the sports cars, it succeeded the Mercedes-Benz 380 which had been introduced only the previous year, using a larger, more powerful engine and more opulent coachwork to meet customers' demands for greater luxury and performance.
The 500K used the same independent suspension setup as had been introduced on the 380, with a double wishbone front axle, double-joint swing axle at the rear, and separate wheel location, coil springs and damping, a world first. Consequently it was a more comfortable and better handling car than Mercedes' previous S/SS/SSK generation of roadsters from the 1920s, and offered greater appeal to buyers, particularly the growing number of well-heeled female drivers of the time.
Pressing the throttle pedal fully engaged the Roots supercharger, inducing the five litre straight-eight engine to produce up to 160 horsepower (120 kW) and making the car capable of over 160 kilometres per hour (100 mph), while consuming fuel at the rate of up to 30 l/100 km (9.4 mpg-imp; 7.8 mpg-US) as it did so.
Three different chassis and eight bodies were available for customers; the two longer "B" and "C" four-seat cabriolet versions rode on a wheelbase of 3,290 mm (129.5 in), and would later be used on other sedan and touring car models. The short "A" chassis, with a 2,980 mm (117.3 in) wheelbase, underpinned the two-seater models: the Motorway Courier, and the 1936 Special Roadster which offered the highest performance. All models featured such advanced equipment as safety glass, hydraulic brakes, and a 12-volt electrical system sufficient to bear the load of the electric windscreen wipers, door locks, and indicators.
The combined production of the 500K (342 cars) including 29 Special Roadsters during its two years in production, and the later 540K (419 cars) from Sindelfingen, the deliveries were:
- 70 chassis without body
- 28 open cars
- 23 sedans with 4 doors (mainly 500K)
- 29 sedans with 2 doors (mainly 540K)
- 12 Coupés
- 6 Autobahn cruisers
- 58 Roadsters
- 116 Cabriolets A
- 296 Cabriolets B
- 122 Cabriolets C
Today, the cars remain highly prized for their heritage and scarcity. When the car collection of Formula One supremo Bernie Ecclestone was auctioned in October 2007 it included five pre-war Mercedes, and his 500K Special Cabriolet fetched almost £700,000 (US$1.45 million).