Well you should never say never. There is one way that higher octane fuel could hurt mixture. It depends on what was used to enhance the octane rating. Fuel distributors could be very susceptible to Methanol additives even Ethanol in too large of proportions cause corrosion in fuel systems. The stainless diaphragm in the fuel distributors has been known to corrode through.
Other than the corrosive properties of octane enhancers no other relationship exists between mixture and octane.
Owner 24 bay BSC
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