Is this the same 440 build in your sig line? If so, which KB piston do you have? Flat top or step head quench head? If it's the quench head, that may not allow you to swap heads.
Compression ratio, for you guys who like to do it "long hand":
(Bore/2) squared=A
A times stroke times pie times 16.387
This is your swept cylinder volume in CC's.
Now, in a seperate equation:
Add head volume, dish volume, gasket volume, and down fill volume. Add this total to the swept total, then divide by the same number.
Is that confusing!
Example for normal .030 over 440:
4.350/2 then squared=4.730
4.730x3.75 stroke x pie x 16.387= 913.26 total swept volume
84cc heads +9.9 cc head gasket+4cc's valve relief + 2 cc down fill= 99.9
So, 913.26 +99.9= 1013.16
1013.16 / 99.9=10.1417
Down fill is the amount the piston is in the hole, or below deck. Use the swept volume equation but replace the stroke with the amount your piston is down, like .018.
Domes and quench or step heads have a opposite volume, so you subtract this amount from the second equation.
God, I must be bored!