Piston and Valve Animation
Old Engine Cutaway

Compression Ratio and Displacement Calculator

This simple tool allows you to calculate the STATIC compression ratio of an engine. It will also allow you to calculate the engine  displacement in Liters and Cubic Inches. See Below for explanations of the fields required.

Static Compression Ratio Calculator
Number of Cylinders
Chamber Volume(cc)
Head Gasket Thickness
Head Gasket Bore
Piston To Deck Height
Piston Type
Dome Volume (cc)
Calculated Displacement and Compression
Displacement inches cc
Compression Ratio to 1

Engine Data Explanation

Calculate your Engine's Compression Ratio Here. Fill out the required fields and you will see the magic. If you want to see what a sample
calculation looks like hit the "Sample" button. Below is a description of each field of data -

Number Of Cylinders - Number of Pistons in your Engine
Bore - Engine Bore in Inches
Stroke - Engine Stroke in Inches
Chamber Volume - Cylinder Head Combustion Chamber Volume in CC
Head Gasket Thickness - Compressed Head Gasket Thickness in Inches
Head Gasket Bore - Bore size of the Head Gasket in Inches
Piston To Deck Height - Positive number is below the deck, Negative Above in Inches

Piston Type -
Dished - Dome Volume is Subtracted
Flat Top - Dome Volume is Subtracted
Domed - Dome Volume is Added
Dome Volume - The Dome Volume as described above for each piston in CC

The Dome volume includes Dish, Valve Relief. For Example if you have a Flat Top Piston with valve reliefs the Dome Volume
would what is cut out for the valve.

If a Domed piston with valve relief the total dome volume would be the Dome MINUS Valve Relief.

For a Dished Piston the Dome Volume would the the total negative volume. All data is entered as a POSITIVE Value and the
Piston type will determine how the number is used.
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