Another question on CR / PI heads / dish size

[trublustang]

I am still confused at CR you can expect based on ported/non ported PI heads combustion chamber volume and various piston dish sizes.

Non ported PI heads: 42cc combustion chamber volume
Stock piston dish size: 17cc
Resulting CR: 9.7

What CR could I expect for example from:
Ported PI heads: 44cc combustion chamber volume
Piston dish size: 19cc
Resulting CR: ?

Do you know of any reliable chart/calculating formula to derive a CR for a modular?

Thnaks guys!