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**Compression Ratio Calculator**

GV (Head Gasket Volume) = Bore(in) X Bore(in) X 12.87 X (Head Gasket Thickness in Inches) |

DV (Below Deck Volume) = Bore(in) X Bore(in) X 12.87 X (Inches Below the Deck) |

HV (Head Volume) = CC's |

VV (Dish, Valve Pocket, Dome Volume) = CC's (Minus for dish or valve pockets, Plus for dome) |

PV (Volume displaced by Piston) = Bore X Bore X Stroke X 12.87 |

Compression Ratio = (GV+DV+HV-VV+PV) / (GV+DV+HV-VV) |

Cubic Inches = Bore x Bore X Stroke X Number of Cylinders X .7854 |

Convert Cubic Inches to CCs = Cubic Inches X 16.386 |

Convert Cubic Inches to Liters = Cubic Inches X .016386 |

Engine in Liters = (Bore(mm) X Bore(mm) X Stroke(mm) X Number of Cylinders X 12.87) / (16386 X 1000) |

Engine in CCs = (Bore(mm) X Bore(mm) X Stroke(mm) X Number of Cylinders X 12.87) / 16386 |

Convert CCs to Cubic Inches = CCs / 16.386 |

Convert Liters to Cubic Inches = Liters / .016386 |

Want to do the math to PROPERLY figure and understand your Compression Ratio?