The Mercedes-Benz W125 is a Grand Prix racing car that was first introduced at the 1937 Grand Prix season and it was produced till the year 1938. It was available with a 5.6 liter supercharged 8-cylinder engine that was capable of producing about 637 bhp at 5,800 rpm along with a 4-speed transverse transmission. The engine capacity was reduced to 3000 cc in 1938 before being replaced with the Mercedes-Benz W154. This model was considered to be one of the most powerful race cars for three decades during its production period. The car was driven by Rudolf Caracciola who had won the 1937 European Championship. The Mercedes-Benz W125 was available with a stiffer tubular frame construction than its previous version and the bodywork was made of aluminum metal. The overall weight of this model was around 750 kg which also includes the weight of the engine of 222 kg which is around 30 percent of the total weight. The gearbox design was like constant mesh type that was able to provided better reliability than the M25 which had sliding mesh transmission. The Mercedes-Benz W125 is expected to have a very stiff suspension that made the difficult for the wheels to stay on the road. This stiffness also made the chassis to flex and rear axle to bend under braking. The car was able to reach a top speed of around 190 mph in 1937 as it was equipped with a streamlined body.
