I only put about 200 miles a year on my 04 Cobra and 04 Mach 1. I am thinking that I would never ruin a cat. Converter. How many of you run ethanol free leaded gas? Is 92 octain lead free better than 93 octaine with ethanol. I only put about 10 gals. Of gas in each car at a time to keep the fuel fresh. What do you guys burn? Jack