A KT100 needs a bit more octane or you run the risk of detonation. Not too much more, say something like 100or 103 is ideal. But don’t use pump gas on a race day, pump gas has too many other chemicals in it’s formulation that will get you disqualified.
Some tracks and local kart shops sell race gas, check with your club first, they can tell you exactly what they use and where you might be able to pick a gallon or two.