Tybo. That's wrong. Higer octane fuel is made for higher compression engine's, it does not and can not affect the compression of an engine that would require an alteration in the dimensions of the the bore, stroke or cylinderhead. An octane rating is a numerical figure that relates to how much squish can applied to the fuel before it detonates due to compression. If this happens (running regular in a hi-comp. Motor). The fuel detonates while the piston is still moving upwards... The damage is like a head on collision and results in cracked pistons, bent conecting rods and cylinder head damage. Not trying to be a dick tybo but the statement you made is wrong. No damage can occur from running a higer octane rating than nessacary except to wallet.