1939 Mercedes-Benz W163

The W163 is much the same as the W154 aside from the new bodywirk and the M 163 V12 engine. Chassis and suspension components are almost unchanged compared to the W125.

Braking was much improved compared to the earlier W125 and W25 designs. The largest drum diameter that fit within the limits of the rim were used. Inside each drum was twin light-alloy shoes which were operated by hydraulic pistons. Cooling to the drum was ample with the inclusion of angled veins which moved the air centrifugally over the out side of the drum.

Of special interest is the position within which the engine was mounted. The V12 sat at a downward angle compared to the chassis. This allowed for the driveshaft to incline downwards, sitting lower near the rear of the car. This meant driver’s seat could be mounted lower which resulted in a lower center of gravity. This drivetrain setup is also observed in the type W154.

In 1938 the AIACR restricted engine size such that the upper limit of engine capacity was limited to 4.5 liters unsupercharged and 3.0 litres supercharged. The result of this regulation caused a slight decrease in power for grand prix cars. In general, 1939 cars had the same power as that of the earlier unrestricted 750kg forumla cars. This meant the new 3-litre formula rules failed to reduce the speeds involved in forumla racing . Furthermore, remarkable improvements in road handling, braking and aerodynamics for the 1938 & 39 seasons kept the cars ahead of their 1937 unrestricted predecessors.

In Detail

submitted by	Richard Owen
engine	Front Longitudinal
position	M 163 V12
aspiration	Twin Roots Superchargers
valvetrain	DOHC, 4 Valves per Cyl
displacement	2963 cc / 180.8 in³
bore	67 mm / 2.64 in
stroke	70 mm / 2.76 in
compression	7.5:1
power	360.2 kw / 483.0 bhp @ 7800 rpm
specific output	163.01 bhp per litre
bhp/weight	492.35 bhp per tonne
redline	8000
body / frame	Aluminum over Oval Tube Frame
driven wheels	RWD
front tires	5.25×17
rear tires	7×19
front brakes	Lockheed Hydrualics
f brake size	x 419 mm / x 16.5 in
rear brakes	Lockheed Hydrualics
r brake size	x 419 mm / x 16.5 in
steering	Worm & Nut
f suspension	Double Wishbones w/Coil Springs, Hydrualic Shock Absorbers
r suspension	De Dion Axle w/Torsion Bar Springs, Hydrualic Shick Absorbers
curb weight	981 kg / 2163 lbs
wheelbase	2730 mm / 107.5 in
front track	1475 mm / 58.1 in
rear track	1412 mm / 55.6 in
length	4250 mm / 167.3 in
width	1750 mm / 68.9 in
height	1010 mm / 39.8 in
transmission	5-Speed Manual
gear ratios	:1
top speed	~330 kph / 205.1 mph