1938 MERCEDES BENZ Typ 320 “Autobahnkurier” (W142) 320 (3.4 L)

Vehicle Overview

The 1938 model of the W142 Typ 320 was the last evolution over the model 290. It featured improvements for comfort and high-speed efficiency.

The Typ 320 featured a 3.2-liter engine in the beginning, in February 1937 when it was shown at the International Automobile and Motorcycle Exhibition in Berlin. With it, the brand closed a gap in the market between medium-sized vehicles and vehicles of the largest format. The four-door version with streamlined bodywork was suspected to be designed by Spohn, one of the most prolific aerodynamically-shaped bodywork builders in the era.

The initial 3.2-liter engine featured 12 counter-weights for the crankshaft, to reduce engine vibrations. The solution worked and the engine ran smoothly. The former updraught carburetor was replaced by two downdraught carburetors. The previously used 4-speed transmission with overdrive function (it was, actually a three-speed gearbox), was replaced by a fully synchronized 4-speed gearbox supplied by ZF company. The fourth gear had a 1:1 gear ratio, which made the engine ran 26% lower than the previous version, at the same speed. That made the Typ 32 W142 IV faster and with a better fuel-efficiency. In late 1938, due to the shortage of high-octane fuel, the engine displacement was increased to 3.4-liter, in order to keep the same 78 hp.

The chassis featured an independent front suspension with a transverse leaf spring. At the top, the wheel was attached to a suspension arm that rested on a helical spring on the inside. The rear dual-joint swing axle had two helical springs on each side, one behind the other. Dual-action hydraulic lever-type dampers were installed on both front and rear axles.