I always thought that cars w/ high compression ratios required high octane to avoid detonation. Octane doesn't have any more power in it right? It just is less flammable, so it can resist detonation under higher compression and thus allow for longer power stroke w/ more force (because of the higher compression).

Is this not true?

So, if this is true, you wouldn't be able to derive more power out of higher octane fuel just because it is higher octane. I thought the high octane kept high compression engines from detonating and causing knocks and pings? Yes?