It doesn't work that way. At all. 10:1 is 10:1 is 10:1 regardless of what the heads are made of. The head material has nothing to do with compression ratio. Nothing. Nada. Zilch. Zero. It will have 10:1 even if the heads are made out of wood. When figuring for dynamic compression, use the static compression figure, plus any other variables (like the intake valve closing event) the calculator calls for.
