The Stovebolt Site Forums The Shop Area Engine Shop Moth balls in gas tank?

Martin is spot-on. This was a perpetual rumor when I was in high school so we asked our chemistry teacher. From what I recall the naphthalene moth balls will burn but won't improve gasoline's octane rating. Then there is another type of mothball (sorry, I can not remember what it is made from). Our teacher told us to only put these in your gas tank if you wanted to put an end to your engine. As I recall, when they are mixed with gas and burned, they give off hydrochloric acid. I do clearly remember he thought it would cause the internal parts of your engine to rust very quickly.