Rebuilding a 2.3-16V..head gasket question

[MDE3]

Does anyone know the original head gasket thickness for a 2.3 16V (Kat or as it is better known "Nam" 9.7 :1 compression), and maybe the true head combustion chamber volume? I have heard 57 cc's, but am open to opinions...or better yet..fact...

I just measured the head combustion chamber on one head at 55.5 cc's. (liquid fill with antifreeze solvent via syringe and flat cover)

Piston is pretty much "0" deck height..actually negative .007"

Piston has 43.2 center wrist pin to crown height.

Bore is still stock at 95.5 mm

Replacement head gasket thickness is .075"..I suspect the original may have been thinner by quite a bit if this engine was indeed at 9.7:1.

Vs = 574.83 cc's
Vk = 71.903 cc's, where Vk is the sum of measured head cavity, calculated volume inside head gasket circumference, valve relief, and upper piston - cyl. wall gap of .5 mm differerential bore to first ring.

Vk: head recess: 55.5 cc's
head gasket gap: 13.65 cc's
valve reliefs: 2 cc's
differential bore gap top 10 cm: .752 cc's
Total: 71.903 cc's

Where CR = (Vk + Vs)/Vk

By my calculations I end up with an actual CR of 9.0 : 1 (or very very close assuming a 0.000" piston/deck differential)...and am feeling a little "gypped...

PS I did go through the search process and found interesting info, but none of it serves to explain the discrepancies I am seeing here...maybe it's my math....however I have redone the process maybe 50 times and come up with the same answers. (why I posted my numerical data in here)

Note..many have suggested that the head has been worked(meaning planed)...and while that is certainly possible the net result of that process should be an increase, not a decrease in C.R.

Sice posting this the first time I have had the chance to verify the cc's on three heads..without knowing whether they were all still stock however....The cc's measured vary from 52.5 cc's to 55.5 cc's...the 55.5 cc's being in a head that is not planed, however it has had the valves and seats cut at least once....

So not only would I like to know the official "new" head gasket thickness, but also the official cc's of the 16 Valve cylinder head...if there is such a number....