Ethanol free gas in Ford Thunderbird Posted February 23 QT sells ethanol free gasoline in my area, but it is only 87 octane. I use their 93 octane premium and add to it "Carb Defender" by Driven Racing Oil to protect against the corrosive properties of ethanol. In addition, I use "NO-Rosion Fuel System Octane Booster" to increase the octane and protect the non-hardened valve seats in my '56 Thunderbird. It is a great substitute for the lead that was once in gas. I have been using both products for several years with no problems.