does anyone know the Piston volume on the oem Piston

?

Or the specific Piston volume of wössner 86,5mm Pistons?
The datasheet tells

-14,8 cm³ but i Need to get the total cm³ to calculate the compressor Ratio,.

.

.

.

why can´t they just tell the real cm³ BUT HAVE TO CALL IT

- OR

+ to oem

? damn im angry

!