The Mercedes-Benz W125 Rekordwagen was an experimental, high-speed automobile produced in the late 1930s. The streamlined car was derived from the 1937 open-wheel race car Mercedes-Benz W125 Formel-Rennwagen, of which also a streamlined version was raced at the non-championship Avusrennen in Berlin.
Driven by Rudolf Caracciola and powered by a 563 kW V12, the car set a record of 432.7 km/h (268.9 mph) over the flying kilometre on 28 January 1938. This remained the highest speed officially timed on a public road for almost 80 years.
History
The main difference from the Formel-Rennwagen Grand Prix race car, which had to adhere to the 750 kg limit, was the engine. While the GP car had the 8-cylinder inline M125, which was rather tall, the record car was fitted with a V12 engine that was lower, which reduced drag.
Given that the first version of the newly built 12-cylinder record-breaking car based on the W 125 Grand Prix car had clearly failed to meet its intended targets at the premiere of "Record Week" at the end of October 1937, the unfortunate situation arose for Daimler-Benz that, under the given circumstances, the next opportunity for rehabilitation did not open up until autumn 1938 - more than six months after the International Automobile and Motorcycle Exhibition (IAMA), the most important showcase for the domestic automotive industry. Under no circumstances did they want to appear there as losers.
Daimler-Benz managed to get the NSKK leadership to specify a date for the next record week that was still before the IAMA. As early as the end of January 1938, the intention was to compete with a new, heavily revised version of the W 125 record-breaking car.
Its power unit had already offered no reason for complaint in the unsuccessful performance of 1937.