Camilo wrote:

I don't know if the higher octane has anything to do with helping out with
the stale gas situation. I do know that with my old I/O, the compression
and/or timing was set up in such a way that low octane fuel caused
knocking, dieseling, and my mechanic told me, would cause damage.

Right, I understand that high octane fuel prevents premature ignition (that
being the whole purpose of high octane fuel), and that premature ignition
causes damage.

Is old fuel more prone to premature ignition? That would be the only
obvious reason for a recommendation to mix with high-octane fuel.

Thanks,

Shawn.