Kevin and All, Your engine should be 9.7-1 compression if it hasn't been modified and and running 91octane gas you probably should be ok at around 5 or 6 btdc...less than halfway down from 0 to bottom of markings plate. If your car came from a low elevation you'll have some carb work to do too, I think. Dave 67 HAZE GREEN Sedan Covington, Wa.