"... the Wallace calculator shows 10.55:1 while the Butler calculator shows 9.65:1 with all of th same information. I entered 4.150 bore, 3.75 stroke, 72cc heads, 15cc dish, .041 gasket, and .000 deck height on both calculators. Am I missing something here?..."
I got 9.59 CR on the Wallace calculator. I added 4.3 to your figures, for the head gasket bore size. If you leave the head gasket bore size box blank, it does show 10.55 CR. i think that explains the big difference.
