After years of searching for a replacement for the lead in 100LL, is the solution upon us? General Aviation Modifications thinks so and demonstrated the new fuel to AVweb in a test flight and engine test cell run last week. The new fuel is called G100UL and has essentially come out of nowhere as a developmental fuel to replace 100LL.
It's made entirely of petroleum components using what GAMI's George Braly describes as well-known refining techniques. What's still unknown is how the fuel's economics will play out and whether it will be competitive in price with leaded avgas. (We don't expect it to be cheaper.)