[jhirasak]

Thanks to all of you that have responded to my questions. After reviewing material available on the web, it appears that gas additives that contain MMT provide the best improvement in raising the octane rating of straight 91 octane pump gas. Now comes the problem of separating advertising hype from actual results. However, mixing 100 octane gas with 91 octane normally available in California seems to be the preferred solution to my situation by many on this forum.

Since I would like to keep my existing ignition advance curve for best performance, I think that I will purchase a few gallons of 100 octane gas whenever I happen to be near a source of such gas and keep a can of octane booster with me to add to the tank when I can only obtain 91 octane pump gas. Since I have a MSD Knock Alert detonation sensor installed on my engine, it is easy to to determine if the current tank of gas has a sufficient octane rating.

Cheers,

John