I have 11:1 CR pistons from Prelude Type S, along with shaved head and H22Z1 bottom end.
Previous compression test results (10.0:1, shaved head, ~80,000km):
196
196
190
196
New compression test results (11.0:1, shaved head, ~10,000kms):
215
215
215
215
Your results depend on more than just the CR of the pistons, they depend on ring seal, cylinder/bore wear, head clearance (don't know exact term for that?), piston compression ratio, and most importantly atmospheric pressure at location of testing.
If you test at sea level, as opposed to 100m above sea level - your compression results will vary.
Edit: You can also do a leak down test, which involves adding oil to the combustion cylinder... this will help seal the rings and determine if you have any blow-by or leakage past the rings. You will observe the compression results go up by a reasonable amount if there is any kind of leakage/problem.
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