In 1920, Walter Bentley produced the first all-English sports car – the 3-litre Bentley. In an age of increasing affordability for the common motorist, this car led the way as a high-end prestige motorcar that every driver aspired to. As various updates were incorporated, the 3-litre became a master of the international racing circuits in the 1920s and 30s, and the Bentley Boys team drivers were household heroes. The German Mercedes-Benz W125 arrived in 1937; a beautiful and lively true racing car that broke new boundaries and became the undisputed winner of its day.

Specifications

			Bentley 3-litre		Mercedes-Benz W125
	Length		4.42 metres		4.20 metres
	Engine		Bentley straight six cylinder 3669cc		Mercedes V8 DOHC 5660cc
	Power		105 horsepower		592 horsepower
	Top speed		102mph		200mph

Design

Here we see two racing cars that couldn't be more different. The Bentley 3-litre, though a classic, really couldn't compete with the new breed of sports cars being developed on the continent. The Bentley ethos was based on fitting as big an engine as possible into what was basically a touring car. The semi-elliptic leaf spring suspension, pedestrian driving position and rolled down canopy couldn't have been more at odds with the modern racing car. It did have a fine reputation as an indestructible champion of its day. Unfortunately, by 1937 its day had gone. As Italian car designer Ettore Bugatti so cruelly termed them, 'The fastest lorries in Europe.'

The Mercedes-Benz W125 was a marvel. Built to replace the great W25 (because of new racing weight regulations) the new car looked fast, and was fast. The bullet-shaped design rested on a fine chassis with independent coil sprung suspension and hydraulic dampeners. This enabled the car to corner at frightening speeds and, with the 5.5-litre engine, release tremendous power. It could even wheelspin at 100mph if the driver was too heavy on the throttle. All-round hydraulic brakes and a close four-speed gearbox added to the sprightly handling.

Engines

From the mid to late 1930s there were no regulations on the size or power of engines that could be fitted into a Grand Prix car. This led to some ominous motors, the W125 being the wildest, sporting the brand new V8 with a screaming 'redline' of 6000rpm.

The Bentley 3-litre engine, though not really any competition for the Mercedes-Benz, was still a great piece of engineering and enabled the team to dominate the international circuit before the dawn of the new racers. A complicated design that ran four valves per cylinder off a single overhead cam, it also used two spark plugs per cylinder. Unfortunately the weight-saving alloy crankcase was lost on the overweight chassis.

The Mercedes W125, producing over 100 horsepower per litre, was one of the most powerful Grand Prix cars ever produced and at the hands of professional driver, Rudolf Caracciola, ran away with the 1937 season.