So if you use 110 octane in a motor that is 9 to 1 compression that there will be no degradation in performance
Correct. Octane rating is essentially a measure of resistance to auto-ignition, not burn speed or burn temperature as some think.
Specifically, high octane fuel does not burn slower or cooler. The energy content and flame speed of pump gas will not vary much regardless of octane rating, although some engines will produce slightly more power with a lower octane fuel. That is partially because the energy content can be slightly higher (different additives) but also because it can actually be beneficial to have a trace of detonation. I wouldn't recommend tuning for that though.
Originally Posted By Banshee
Too much octane will have a negative effect on an engine not needing higher octane.
No; using fuel with more octane than the engine needs will have a negative effect on your wallet.
