Mercedes-Benz W 125
The Mercedes -Benz W 125 was the Grand Prix racing cars of Daimler -Benz AG in 1937. Since the rules from the 1938 engine capacity limited and therefore the power was reduced, was the 600 hp 125 W until the early 1980s as the most powerful and most impressive car that competed in Grand Prix racing until then.
History
The W 125 was the successor to the Mercedes -Benz W 25, the first " Silver Arrow ", had developed the Mercedes for the so-called 750 - kg formula and started from 1934. The two models underlying formula weight (750 kg = maximum weight of the car without driver, fuel, oil, water and tires ) should apply to 1936 originally, but was extended until 1937.
The relevant designers of the W 125 were Max Wagner and Rudolf Uhlen skin. Uhlenhaut undertook self tests, racing participation but were denied. Knowing some of the deficiencies of the previous model (extreme changes in camber and toe during compression), they designed a chassis with de Dion rear axle instead of a vibrating or oscillating axle. The front wheels were suspended at different length upper and lower wishbones. The frame of the car consisted of oval pipes (1.5 mm thick steel plate ) with four cross members made of round tube.
Was powered the first 125 W from an 8 - cylinder in-line engine of the type M 25, M 25 E The version from 1936 with 4.74 liters and 473 hp is on display at the Mercedes- Benz Museum as a separate exhibit. During the year 1937 the engine capacity was increased to 5.66 liters, as the power of this variant are up to 646 hp stated. In racing, however, the tire wear put the Leistungsseinsatz limits, Auto Union Type C had about 500 hp.
When Avusrennen 1937, Mercedes next to the " normal" W 125 and those with streamlined fairing one also fully clad special racing car with a 5.57 -liter V12 engine one, which carried up to 598 horsepower and enabled a top speed of over 370 km / h. The driver of that car was Manfred von Brauchitsch.
Due to the rule changes for 1938, which limited the displacement of compressor motors to 3 liters, the successor to Mercedes -Benz W 154 was developed with a V12 engine.
See also: Silver Arrow
Data
The W 125 scored 1937 first six, nine second and six third-place finishes in the Grand Prix. The drivers were Rudolf Caracciola, Manfred von Brauchitsch, Hermann Lang, Christian Kautz, Richard Seaman and Goffredo Zehender.
Record car W 125
On the basis of the Grand Prix car W 125 Mercedes built in 1937 set a world record car with a V12 engine ( 5577 cc ). This V12 engine had indeed less displacement than the 8- cylinder in-line engine M 25 but was flatter and more aerodynamic. Rudolf Caracciola achieved with this car in the fall of 1937 already has a top speed of 395 km / h, which almost became his undoing, as the front of the car raised at this rate. Then the body was newly developed. Among other things accounted for by changing the engine cooling on ice, a conventional radiator so that the air inlet opening is reduced at the bow and the drag coefficient was reduced to 0.157. Additional carburetor caused an increase in engine power of the DAB V12 supercharged engine from initially 419 kW ( 570 hp ) to 541 kW ( 736 hp) at 5800 rpm.
With the optimized car, but with the same engine and chassis as 1937 Caracciola scored in the displacement class 5000-8000 cm ³ on 28 January 1938 on the Frankfurt -Darmstadt motorway over a distance of 1 km flying start 432.7 km / h as average round- trip ticket. This is the highest speed that was until today ever driven on a public road.