sorry for the delayed response,
I have been out of town, but I would definately have to agree with Marc Elliot and Doug Schuler that a couple of karts in GJ that were in front of us were using addatives that were not the most pleasent thing to breath and I am sure they were not good for our bodies. Both Marc and I came in from the pre-final feeling very sick. I have seen many good ideas on regulating fuel and I believe that they would work very well to stop those cheaters!