Hi Woodsy, Downunder gave me the info on acetone. Apparently it gives better idle and it also absorbes moisture from the methanol. Why only 3%, I don't know but perhaps the experts can enlighten us. Sigrun also has written a bit on it in his post on this thread. I've tried this brew and am happy with the results. It's also cheaper then nitromethane, only 6.90 for 1/2 a liter. There are some differing views on this thread but all the info has had some merit I think. Regards, John.