I know that the tolerances are all over the place for these motors so I am measuring piston deck height(amount piston in hole) as well as gasket thickness and head volume to determine compression ratio. My question is what is the average cutoff point where 93 octane can no longer be used and race fuel must be used to prevent detonation? Once again I understand there is no exact CR just looking for an estimate. Thank you for your time.
Jared
Jared