Question · Engineering basics
What is engine displacement?
Engine displacement is the total volume swept by all of an engine's pistons over one full stroke, usually quoted in litres — for example, "2.0 litre."
Displacement is a measure of physical size: add up the volume each cylinder's piston sweeps as it travels from the top to the bottom of its stroke, multiply by however many cylinders the engine has, and that total is the displacement — expressed in litres for a bigger figure, or cubic centimetres for a smaller, more precise one.
It's a rough guide to an engine's potential, not a fixed rule: a larger-displacement engine has more room to burn fuel and air per cycle, but a turbocharged, smaller-displacement engine can match or beat it by forcing extra air in artificially. So a "2.0 litre" badge tells you the engine's physical size, not necessarily how much power sits behind it. That gap between size and output is exactly the kind of engineering detail car art is drawn from.
Written by Craig Fearn, Petrol & Ink.