Engine Displacement Calculator

Both measure the same thing (total swept volume of every cylinder combined), just in different units. 1 cubic inch equals exactly 16.387064 cubic centimeters, fixed by the 1959 International Yard and Pound Agreement (1 inch is defined as 25.4 mm exactly, so 1 in^3 = 25.4^3 mm^3 = 16,387.064 mm^3 = 16.387064 cc). A 350 ci small-block Chevy is 5,735 cc, or 5.7 liters. Cubic centimeters and milliliters are the same unit, which is why motorcycle people say "600 cc" and chemists say "600 mL" for the same volume.

Stroke divided by bore tells you the engine's geometry, and engineers use one of three labels based on the result. Below 1.0 is oversquare (a short-stroke, big-bore engine, like a Honda S2000 with an 87 mm bore and 84 mm stroke giving 0.97). Above 1.0 is undersquare (a long-stroke, narrow-bore engine, like a diesel truck engine at 1.20 or higher). Exactly 1.0 is square, as in the Honda K20 at 86 x 86 mm. The original 350 small-block Chevy is oversquare at 4.00 x 3.48 inches.

Look for a line that reads something like "Bore x Stroke: 86 x 86 mm" in the technical specifications section of the manual, the manufacturer's press release, or a sales brochure. American V8 specs often list inches: "4.00 x 3.48 in" describes the classic 5.7 L Gen I small-block 350, not the LS1. Both numbers are physical dimensions of one cylinder: bore is the inside diameter of the cylinder wall, and stroke is the distance the piston travels from top dead center to bottom dead center.

Displacement scales linearly with cylinder count, so changing from 4 to 6 cylinders at the same bore and stroke adds 50% more swept volume. Per-cylinder volume helps describe the engine's geometry, but total power, torque curve, smoothness, and usable RPM also depend on airflow, combustion, valvetrain, tuning, mass, and load. Use this calculator for displacement, not a performance prediction.

Divide by 1000. A 2,000 cc engine is 2.0 liters. A 5,735 cc small-block Chevy is 5.7 liters, which is why it's marketed as a "5.7 L V8". 1 cubic centimeter and 1 milliliter are the same volume, and 1 liter is 1000 mL, so the cc-to-liter step is just a decimal shift. Manufacturers round to one decimal place for marketing ("3.5 L V6") even when the actual displacement is 3,471 cc; the calculator shows two decimal places so you can spot the difference between a 1.99 L and a 2.01 L engine that both get badged as "2.0".