i think i read they mixed one quart to a full tank then skipped a tank then one quart to a full tank and so on. i guess you could play with it and see what work's for you. just don't go over board and mix some thing like 2 quart's to half a tank and i think you'll be okay. i would rally start out with a small ratio and work up a little bit. but i would never mix more than one or one and a half quart's no matter what. let us know how it work's.