L&M Newsletter

Compression Ratio Calculator

Extended compression ratio calculator that takes into account factors that are usually missed on other compression calculators that are available on the internet. This is a work in progress, values that are obtained by using the calculator below are theoretical and should be double checked for real world applications.


  • # of Cylinders - Number of cylinders in the engine
  • Bore - Cylinder bore diameter in inches
  • Stroke - Stroke length in inches
  • Rod Length - Length of the engine rods in inches
  • Gasket Bore - Gasket bore diameter in inches
  • Compressed Gasket Thickness - Thickness of the head gasket in inches
  • Block Deck Height - Height of the block deck in inches
  • Top Ring Down - Top ring down measurement of the piston in inches
  • Chamber Volume - Combustion chamber volume in cubic centimeters
  • Dome (-) Dish (+) - Piston dome/dish volume in cubic centimeters. Postiive for dish, Negative for dome.
  • Piston / Deck - Piston to deck clearance in inches

# of Cylinders
Rod Length
Gasket Bore
Compressed Gasket Thickness
Block Deck Height
Top Ring Down
Chamber Volume
Dome (-) Dish (+)
Piston / Deck
Total Volume
Cylinder Volume
Clearance Volume
Gasket Volume
Top Ring Volume
Deck Volume
Piston Top Land
1/2 Stroke
Comp. Ht.
Cubic Inches
Compression Ratio