is the diameter of the cylinder bore, the stroke movement of the piston stroke distance dead center and a bottom dead point.
For example:
a car engine, 80 mm bore, 90 mm stroke, four-cylinder. Then displacement so calculated as follows:
a cylinder displacement:
40 (radius) mm x3.14×90 = 452160 = 0.45 liters cubic mm, the total engine displacement = 0.45X4 = 1.8L [ 123]