Enter the bore, stroke and number of cylinders, in inches or millimetres, and get the engine displacement in cubic inches, cubic centimetres and litres.
Displacement is the swept volume of all the cylinders. Each cylinder contributes the area of its bore multiplied by the stroke: pi divided by 4, multiplied by the bore squared, multiplied by the stroke. Multiplying by the number of cylinders gives the total, which is then expressed in cubic inches, cubic centimetres and litres (1 cubic inch equals 16.387 cubic centimetres). Displacement is calculated from the nominal bore and stroke figures; an overbore during a rebuild increases it slightly, and the figure says nothing by itself about power, which also depends on airflow, compression and engine speed.
How is engine displacement calculated? Per cylinder, displacement is pi/4 times the bore squared times the stroke. Multiply by the number of cylinders for the total, then convert: cubic inches times 16.387 gives cubic centimetres, and dividing cubic centimetres by 1000 gives litres.
What does a 5.0 litre engine mean in cubic inches? About 305 cubic inches. Litres are cubic centimetres divided by 1000, and cubic inches are cubic centimetres divided by 16.387, so 5000 cc divided by 16.387 is roughly 305 cubic inches.
Does a bigger displacement always mean more power? No. Displacement sets the volume the engine can draw in per cycle, but power also depends on engine speed, airflow, compression, fueling and tuning. A smaller turbocharged engine can out-produce a larger naturally aspirated one.