My Motor Magazine auto repair manual lists Chevrolet compression ratios from 1940 to 1953 from 6.5:1 up to 7.5:1, and compression pressures from 110 to 112. Now, that can't be correct, but I wouldn't get too concerned about consistent pressures of 85 pounds. The next gauge you try might average 100 pounds or more. Uniformity is much more important than the gauge numbers.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!