M any engine builders agree that around 9.5:1 CR is the safe max, for iron heads on pump gas.
Keep in mind that this is a rule of thumb and that there are many parameters involved such as quality and octane of fuel, camshaft, quench height, chamber design, spark plug selection, etc. So, if you calculate to a 9.67 CR, that doesn't spell instant doom. Well, maybe if you chose the wrong camshaft.
1968 400 Coupe, verdoro green, black vinyl top, auto 1969 GTO Judge coupe, Carousel Red, manual 1971 Trans Am, cameo white, auto 1970 Buick Skylark Custom Convertible 350-4(driver), Fire Red, white top, auto 1972 Buick GS Stage 1, Royal Blue, black vinyl top, auto
