ok, I checked my book with the casting number and my heads have 105cc chambers. I calculated c.r. using:
deck height: 0 (to be safe)
gasket bore: same as cyl. bore (to be safe)
dome: 15cc (I think it's less, but check the pic)
gasket thick: .04
bore: 4.128
stroke: 3.76

I get 9.34:1, and I think I was very conservative with items that will end up decreasing the comp. a tiny bit in reality.

Here is a pic of the pistons when I had the heads off.