Quick Check Engine Compression ratios
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Quick Check Engine Compression ratios
The Calculation of an engine's compression ratio ( C.R. ) is based on the formula :
CR= (SV+CV)/CV
SV= Swept Volume for one cylinder in CC's= Bore x Bore x stroke x 12.9
CV= Clearence Volume for one cylinder in CC's= HV minus EDV plus DV plus GV
HV= Head Volume (measured in CC's)= Best if measured because head volume vaires
EDV= Effective Dome Volume (measured in CC's)= Dome volume minus valve relief and/or dish volume
DV= Deck Volume clearance (piston to deck) (measured in CC's) = Bore x Bore x Deck Height x 12.9
GV= Gasket Volume (measured in CC's)= Gasket Bore x Gasket Bore x Compression Thickness x (12.9 or enter known gasket volume)
edit: Cubic Inch Displacement measurement
Bore x Bore x stroke x .7854 x 4(cylinders)
Thought this should be in H-T to be archived if someone needs these formulas. If anyone have anymore usefull formulas please feel free to post them.
Thanx
Ace
CR= (SV+CV)/CV
SV= Swept Volume for one cylinder in CC's= Bore x Bore x stroke x 12.9
CV= Clearence Volume for one cylinder in CC's= HV minus EDV plus DV plus GV
HV= Head Volume (measured in CC's)= Best if measured because head volume vaires
EDV= Effective Dome Volume (measured in CC's)= Dome volume minus valve relief and/or dish volume
DV= Deck Volume clearance (piston to deck) (measured in CC's) = Bore x Bore x Deck Height x 12.9
GV= Gasket Volume (measured in CC's)= Gasket Bore x Gasket Bore x Compression Thickness x (12.9 or enter known gasket volume)
edit: Cubic Inch Displacement measurement
Bore x Bore x stroke x .7854 x 4(cylinders)
Thought this should be in H-T to be archived if someone needs these formulas. If anyone have anymore usefull formulas please feel free to post them.
Thanx
Ace
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