Compression ratio is nothing more than a mathematical formula. It is the total volume of the cylinder with the piston at the bottom of the cylinder vs the volume of the cylinder with the piston at top dead center. Total volume includes the combustion chamber area.
Engines with high duration cams bleed off compression at cranking speeds so they would show lower psi compared to the same engine with the same compression ratio but with a stock cam. So no you cannot assume higher compression readings mean high compression ratio.
Steve Strasemeier (70SS 396, Fathom Blue/White Stripes) My 70SS
A forum community dedicated to Chevrolet Chevelle owners and enthusiasts. Come join the discussion about restorations, builds, performance, modifications, classifieds, troubleshooting, maintenance, and more!