Engine Size and Compression Calculator

Fill in either SAE or Metric values by double clicking on "number". Then click on when finished.
Cylinder Diameter (inches) Cylinder Diameter (mm)
Stroke Length (inches) Stroke Length (mm)
Number of cylinders Number of cylinders
Chamber in cc's Chamber in cc's
Piston dome in cc's (Dome = positive, 
Flat = 0, dished = negative number)
Piston dome in cc's
Gasket Thickness in inches (add plus or 
minus amount piston is in the hole)
Gasket Thickness in mm (add plus or 
minus amount piston is in the hole)

The displacement is cubic inches or liters.

You also have a Compression ratio of :1 

Engine Specification Calculator
Engine Item  MM  Inches  Measurement 
Engine Bore 
Engine Stroke 
Deck Height *
Combustion Chamber CC's
Your Compression Ratio is
Number of cylinders 
Your Displacement is :
Solve for which variable ? 

mm to inch conversion (Just for fun) 
mm inch fraction
Enter a value in either the mm or inches box, then click the mouse anywhere outside of that box, and it will instantly calculate the other values for you. 

* Measuring Deck Height: The Deck Height measurement is from the top of the block or cylinder down to the top of the piston, if the piston sticks up above the top of the block or cylinder, the deck height will be negative ( -.010") Remember to figure in the thickness of your headgasket (if you have one) into your deck height. (if your deck is -.020, and your head gasket is .100" thick then your deck would be .100 + (-.020) = .080) If your deck is -.100 and your head gasket is .050" thick, I think you may have a problem. .050 + (-.100) = -.050

* Pop up pistons: If you have pop up pistons, you will need to measure the cc's lost by the dome of the piston and subtract it from your Combustion Chamber CC's measurement, or add the cc's if you have a dished piston.