Ok, I have seen where shaving the head increases compression, BUT, I have seen cut .100 and get 9.2 - 1 and also seen the same cut gets 11 - 1 . What the heck gives. I want to cut .075 what will I get from this cut ?

Why do you want to cut .075? That is doing it backwards. You need to decide what compression ratio you want, and then calculate how much to cut. The bore and stroke, deck height, gasket bore and thickness, and existing chamber volume, all affect how much to cut the head to get a particular CR.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

D

And some people, not me!, make math and measurement mistakes and the numbers vary.

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Hyper_pak

As DI correctly points out at the beginning of His post, the jump will be more if You were to do the same cut on a 170 vs a 225..................