Compression ratio calculators??

[art leong]

Originally Posted by Dave Casey

13.54 to 1

I look at as the volume with the piston at bdc divided by the volume with the piston at tdc

convert all values to cc's is easiest for me

16.387 cc's per cu inch

bore and stroke volume + deck volume + chamber volume +gasket volume-dome volume
divided by
deck volume + gasket volume + chamber volume - dome volume

Thats the way i thought it was calculated. But why are the calculators on line so far off? It seems like simple math to me. I just wasn't sure of the formula.