Compression Calculator
Calculate compression ratio and displacement for internal combustion engines. Enter cylinder bore, stroke, and combustion chamber volume to get precise results.
Published by:
isCalculator Editorial Team
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How to use this tool?
This calculator computes the Compression Ratio and Total Displacement of an engine using metric units (mm and cc). Follow these steps:
- Enter Bore (mm): The diameter of each cylinder.
- Enter Stroke (mm): The distance the piston travels.
- Enter Chamber Volume (cc): The volume of the combustion chamber (including head gasket thickness).
- Enter Number of Cylinders: Default is 1; change as needed.
- Click "Calculate": The results appear below:
- Compression Ratio: Shows as X.XX:1 (e.g., 10.50:1).
- Displacement (cc): Total engine displacement in cubic centimeters.
Note: All inputs must be positive numbers. Bore and stroke are in millimeters; chamber volume is in cubic centimeters. The formula is displayed below the results for reference.
Previous Results
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Frequently Asked Questions
Compression ratio is the ratio of the volume of the cylinder and combustion chamber when the piston is at bottom dead center to the volume when the piston is at top dead center.
Displacement is the total volume swept by all pistons. It is calculated as π/4 * bore^2 * stroke * number of cylinders.
Bore and stroke are in millimeters, chamber volume in cubic centimeters (cc). The result displacement is in cc.