[Danr55]

Have you ever tried Lucas Octane Booster? It's about $9.00 a bottle and is clearly marked "Not for street use" That should be some indication of how well it works. It's easier to carry on long trips than race gas and it mixes just right with 25 gallons of 91 octane. My 11.5:1 cleveland motor likes it just fine. The carb mixture setting is about the same as it is with 110 octane, leaded race fuel.