W125 Rekordwagen

1937 Mercedes-Benz W125 Rekordwagen The original body stays at the museum, when the car goes to events, they place a replica body on this chassis as the original is too valuable and fragile
In order to complete the record, the car needed to be as sleek as possible. Measurements done in the wind tunnel four decades later showed the body had a drag coefficient of only 0.170. Then there was the engine, a 5.6-liter V12 with 765 horsepower (563 kilowatts) in 1938. Thanks to extra carburetors, it packed an additional 29 hp (21 kW) over the original specification of the engine, which had been used eight weeks earlier in an aborted record attempt. During that period, the engineers also worked on improving reliability and optimizing the fuel/air mixture supply to each of the twelve cylinders. In addition, the body was basically redesigned from the ground up to boost aero and it benefited from the expertise provided by aircraft manufacturers. The engine featured a bespoke ice-cooling system by placing the radiator in a container with 5 kilograms (11 pounds) of ice and 48 liters (12.6 gallons) of water.
Set a world record in January 1938 when Rudolf Caracciola reached a speed of 432.7 km/h (268.9 mph) on the Autobahn - the fastest speed ever recorded on a public road. Caracciola's record remained unbeaten all the way until November 2017, when Koenigsegg set their record of 277.87MPH with the Agera RS; almost 80 years later.

New 1937 Mercedes-Benz W125 Rekordwagen. The original body stays at the museum, when the car goes to events, they place a replica body on this chassis as the original is too valuable and fragileIn order to complete the record, the car needed to be as sleek as possible. Measurements done in the wind tunnel four decades later showed the body had a drag coefficient of only 0.170. Then there was the engine, a 5.576-liter Daimler-Benz V12 DAB supercharged with 765 horsepower (563 kilowatts) in 1938. Thanks to extra carburetors, it packed an additional 29 hp (21 kW) over the original specification of the DAB-engine, which had been used eight weeks earlier in an aborted record attempt. During that period, the engineers also worked on improving reliability and optimizing the fuel/air mixture supply to each of the twelve cylinders. In addition, the body was basically redesigned from the ground up to boost aero and it benefited from the expertise provided by aircraft manufacturers. The engine featured a bespoke ice-cooling system by placing the radiator in a container with 5 kilograms (11 pounds) of ice and 48 liters (12.6 gallons) of water. Set a world record in January 28, 1938 when Rudolf Caracciola reached a speed of 432.7 km/h (268.9 mph) 1 km flying start and 432.4 km/h (268.7 mph) 1 mile flying start on the Reichautobahn - the fastest speed ever recorded on a public road. Caracciola's record remained unbeaten all the way until November 2017, when Koenigsegg set their record of 277.87MPH with the Agera RS; almost 80 years later.