"deck height (DC) volume is the volume of area when piston is down in the hole at TDC."

How or where do I get that? I have the deck hight - Compression hight = 1.645"",crank to deck distance = 9.8" and my bore = 4.281 and using that 118cc chamber figure. My problem is that a lot of those calculators use different terminoligy's or use some I do not understand.
I probably should take engine math 101 sometime. heh heh .