Engine displacement is the measure of the total cylindrical volume through which the pistons of an engine move from one end of the stroke to the other. The formula to determine the displacement of an engine is: Displacement = .7854 x Bore x Bore x Stroke x Number of Cylinders For example: The displacement of the 4.6L V8 engine is: 280.3 (0.7854 x 3.55 x 3.55 x 3.54 x 8).