The GAMI STC AML which covers your plane and the entire fleet of gasoline-powered engines has been fully approved by the Wichita ACO, and has been sitting at HQ headquarters for 4 1/2 months waiting on an executive’s signature (or permission for the Wichita office to sign it). In my opinion, it faces two problems: 1) the FAA can’t sign it and still claim that E.A.G.L.E ($120,000,000) of funding for the FAA is still needed if a drop-in replacement has already been found, and 2) The five oil companies currently manufacturing 100LL have powerful lobbies and don’t want their fuel to be replaced by an unleaded one.
Achieving 100 Octane Unleaded Fuel is no longer a technical problem. It is a political one.