I'm typically skeptical of additives, they promise the world but often don't deliver anything but a lighter wallet. Until now. I recently decided to try a product with the name of "Sea Foam". I don't know what they put into the stuff but when you open it, it has a strong odor similar to Acetone or something like that. I dumped it into my full tank and by the time the next fill up happened I noticed a lot more pep. Guys at work had told me about this and having all the fuel problems I have had, decided to try it. I think it's a good product and lives up to the claims they make on the bottle.