
4 LIGHT AND HEAVY VEHICLE TECHNOLOGY
Engine rev/min —►
Figure 1.2 Engine power and torque curves
crankshaft speed are usually quoted. For example, the
high-performance engine used in the Mercedes-Benz
500 SL cars is claimed to develop, according to DIN,
180 kW at 4750 rev/min.
Engine torque
Also usually included on an engine performance graph
is a torque curve, which is obtained by plotting crank-
shaft torque, or turning effort, against engine speed.
(Figure 1.2). The engine torque, of course, is derived
from combustion pressure acting upon the cross-
sectional area of the piston, the resulting force from
which applies a turning effort to th ...