http://www.carcraft.com/techarticles...tio/index.html
buradan alıntıdır..
What Is Compression Ratio?
There are five factors that affect compression ratio: cylinder swept volume, clearance volume,
piston dome or dish, head-gasket volume, and chamber volume.
Piston Dome
Note that clearance volume does not take into account any pop-up domes or sunken-in dishes on the head of the piston. These configurations also increase or decrease volume in the combustion chamber and affect the compression ratio. The manufacturer's catalog will list the displacement in cubic centimeters of the dishes or domes on the piston, but we've found that it's not consistent whether they express the cc's of a dish as a positive or a negative number. For the purposes of calculating compression, we prefer to view the cc's of a
dish as a positive number because a dish adds volume to the cylinder (
and reduces the compression ratio); a
dome is a negative number because it subtracts volume from the cylinder (and
increases the compression ratio).
bu konuda sonuçlanmıştır.. ;) Dish'li piston CR yi düşürür, Dome'lu piston ise arttırır..