The San Diego club has someone bring in, I think about 103 octane, fuel to each race. Everybody runs the same fuel, no problems. But that doesn’t mean it’s the best fuel you can use for peak performance on all engine. Sure it was great for the TT 75, but probably not the best choice for the KTs.Just for general info. At the 4 Cycle Super Showdown in Phoenix last month we spec'ed our normal club race spec fuel, VP MS98. Mostly to make tech a little simpler. The race was strictly World Formulas and LO206's. No complaints, no issues.
Do you know how many CC’s are in the combustion chamber? Knowing what the compression ratio is would be a big help in determine what octane you need. If the compression ratio is anything like a clone, you would most likely run best with the lowest octane you can find.
Octane is not a measure of the power you will get out of the fuel; it’s a measure of the fuels ability to resist detonation. Low compression ratio engines run best with low octane fuel. If you raise the compression you might need higher octane fuel, but it’s the higher compression that will give you more power, not the higher octane fuel. The higher the compression, the better chance you have of getting detonation, and this means you need higher octane.
If you can run low octane fuel, without detonation, you’ll get more power from it.