gasoline... seriously, our old low-compression engines do not require anything special about the fuel. Many comment about the ethanol/alcohol and how it can deteriorate some seals, gaskets and rubber parts, but it won't hurt your 216.
Since the "corngas" as some call it IS NOT going away, and in fact some states have mandated higher percentages of it in gas, we will have to get used to it, and replace/upgrade seals, etc. to handle it...
