I purchased new tanks earlier in 2009 for my 1992 unfinished Kitfox that I had recently purchased, unbuilt. If you've read my recent posts about the BSS (brown sticky stuff) that came from my tanks when exposed to auto fuel, you will understand when I state "USE ONLY AVIATION FUEL. YOU DON'T KNOW WHAT ADDITIVES HAVE BEEN ADDED TO AUTO FUEL" Last Monday, I cleaned my carbs of the BSS, and the engine has run perfect since then. First flight comes next Saturday. Bruce Estes