Calculators

To help you figure out exactly what parts you need to build that perfect machine, United Engine and Machine has put together the following group of calculators and converters.


  • Compression Ratio Calculator

    Static and Dynamic compression ratio. (considers cam timing and rod ratio)
    This calculator will give you the proper compression ratio with a known piston head volume. It will also estimate a dynamic effective compression ratio taking into account the cam timing and rod ratio.

  • Effective Compression Ratio Calculator

    (considers cam timing and rod ratio)
    This calculator will give you a dynamic compression ratio taking into account cam timing and rod ratio.

  • Piston Calculator

    This calculator will give you the proper piston head volume with a known compression ratio.

  • Measurement Converter

    Convert inches to millimeters or millimeters to inches.

  • Ring End Gap Calculator

    Using this calculator, you can obtain the proper ring end gap requirements for KB Pistons using end gap factors from inside the front cover of the KB catalog or on this website in the tech article titled "Special Clearance Requirements for the KB Piston."

  • Piston Compression Height Calculator

    Use this calculator to get the approximate piston compression height.

  • Deck Clearance Calculator

    This calculator will compute the deck clearance for above or below deck applications.

  • Engine Displacement Calculator

    Find the engine displacement based on stroke and cylinder measurements.

While using these calculators in your planning, please remember the following:

  • While these calculators will calculate out to six (6) decimal places, they will round to three (3) decimal places when they are displayed, and any figures you enter will also be rounded to three (3) places when the results are displayed.
  • Piston Head Volume and Deck Clearance. Values for Piston Head Volume and Deck Clearance can be entered as both positive or negative values. Negative numbers indicate a reduction in cylinder head volume. Pistons with pop-ups or pistons sticking out above the deck will reduce chamber volume and will usually require a negative number. Pistons with a dish or pistons below deck increase chamber volume and receive a positive value. Located above each picture in the KB Catalog is the value for the piston head volume shown in positive or negative numbers.
  • Deck Clearance. Deck clearance should be measured from the top of the block to the flat portion of the piston. Do not measure to the top of the pop-up or the bottom of a dish. With some pistons this flat area may be very small (example: Chrysler Hemi is only a line at zero deck).
  • Gasket Bore. If you do not have the exact gasket bore use the cylinder bore in its place.
  • Piston Head Volume. On the piston calculator many times you will come up with a piston head volume that approaches zero. When this happens the valve reliefs and the pop-up are approximately equal in value.