1914 Mercedes 115HP Grand Prix

In 1914 Mercedes-Benz would make a triumphant return to successfull Grand Prix racing. That year Mercedes raced a 115HP double seater with the superior engineering. Previous aircraft engine design gave Mercedes valuable experience in lightweight construction. They particularly applied this knowledge to the devleopment of the 4.5-liter engine. The result was exceptional power-unit which excelled in several areas.

For the valvetrain, Mercedes used four valves per cylinder. This made the 1914 GP car, the first DaimlerChrysler product to feature two exhaust and two intake valves in a single combustion chamber. Such a setup allowed the engine to revolve safely at 3200 rpm. During the period, this was the only car that could achieve a redline over 3000 rpm.

The 115HP was conservative in design. Unlike some of the competition there was an absense of front brakes and only one overhead camshaft. The simplicity of the car let Mercedes focus more on reliability with strong construction materials and methods.

With their potent package, Mercedes won first, second and third in the 1914 French Grand Prix held at Lyons. After the Lyons victory one of the cars was shipped to England for a showroom display. Shortly after delivery of car to England, World War One broke out. Immediately the car was turned over to Rolls-Royce for studing. This very car had had huge influence on the Rolls Royce Hawk engine which was made after the study.

Indeed Mercedes develeped the superior engine in 1914. The powerplant proved itself so good in competition that eventually the British would copy the design to aid the war effort.

In Detail

submitted by	Richard Owen
engine	Water-Cooled, M93654, Inline-4
position	Front Longitudnal
aspiration	Natural
valvetrain	SOHC, 4 Valves per Cyl
displacement	4483 cc / 273.6 in³
bore	93 mm / 3.66 in
stroke	165 mm / 6.5 in
power	85.8 kw / 115.1 bhp @ 3200 rpm
specific output	25.67 bhp per litre
bhp/weight	106.57 bhp per tonne
redline	3200
body / frame	Pressed Steel Frame
driven wheels	RWD
front tires	815×120
rear tires	920×135
front brakes	None
f brake size	mm / in
rear brakes	Drums
r brake size	x 343 mm / x 13.5 in
steering	Worm & Nut
f suspension	Rigid Axle w/Semi-Elliptic Springs, Friction Dampers
r suspension	Rigid Axle w/Semi-Elliptic Springs, Friction Dampers
curb weight	1080 kg / 2381 lbs
wheelbase	2845 mm / 112.0 in
front track	1330 mm / 52.4 in
rear track	1350 mm / 53.1 in
length	4100 mm / 161.4 in
width	1700 mm / 66.9 in
height	1400 mm / 55.1 in
transmission	4-Speed Manual
gear ratios	3.00:1, 1.50:1, 1.20:1, 1.00:1, :1
top speed	~185.1 kph / 115.0 mph
drag	6 Cd