Sunoco has a 104 unleaded race gas that may be available at your race track. Years ago, a local gas station used to have one pump that sold it, but you couldn't technically pump it straight into your car unless it was on a trailer. Pump it into a gas can. Used to run it in my GN mixed with 91 premium(highest available locally at the pump). https://www.sunocoracefuels.com/fuel/260-gt-plus
Here's Sonoco's response about using av gas; We actually used to make av gas so we know a little about both. 100LL, like most fuels, is a fuel with properties that make it good for some applications. It’s octane rating is determined by a different method than those used for automotive fuels and it’s designed specifically for the usage that piston engine aircraft see. Makers of av gas don’t make it with cars in mind. Av gas specs allow a higher final boiling point than most race fuels have, which isn’t a good thing, but most mild race engines can tolerate that. Av gas specs also limit the amount of detergents and additives that help shelf life, but that may not be a problem for certain race engines either. Av gas cannot contain oxygen, so it’s power potential is limited relative to some race fuels as well as most pump gas for that matter. That said – as you know - many race engines can tolerate av gas. Typical reasons someone might use av gas versus racing fuel would be price and/or availability. The latter is becoming less of a virtue as airports etc. have become increasingly restrictive about selling av gas to non-aviation customers. So those that are still putting av gas in cars might be doing it save money… it is certainly cheaper than race fuel. I have a hunch that if the price were the same, folks probably would prefer a fuel made for a car. Thanks for the inquiry, Mike / Sunoco
