Use only premium-grade unleaded gasoline. The octane number should be at least 91. Details can be found on the gas pump. The octane number is the average value of the Research Octane Number (RON) and the Motor Octane Number (MON): (RON + MON) / 2, also known as knock resistance. Reformulated Gasoline (RFG) and/or unleaded gasoline with additives can be used if the concentration of the additives in the fuel does not exceed 10%, e.g.:

• Ethanol
• TAME
• ETBE
• IPA
• TBA

For MTBE, the concentration should not exceed 15%.

The concentration of methanol in gasoline including other additives must not exceed 3%. Using mixtures of methanol and ethanol is not permitted. Gasohol, a mixture of 10% ethanol and 90% unleaded gasoline, can be used. All of these mix fuels must fulfill the fuel requirements, e.g.:

• knock resistance
• boiling point
• vapor pressure