We had a similar problem with a Stargazer system in a 97' ProStar 190. After inverting the tach reading, the pull was consistent without a skier, but was horrible skiing @ 34 and 36mph. It would slow down way too much into 1, then race away the rest of the course. We ended up having to go in and make dramatic changes to the "Internal Settings". Perfect Pass was very helpful in supplying instructions on how to access and change, but not so much when it came to advising on some numbers that would work. Internal settings on our system are for "Ball 1", "Ball 3", and "Ball 4 to Exit". There's different numbers for light skiers, heavy skiers, 34, 36, etc.. Generally the default numbers were @ 10, 60, and 30, respectively. We arrived at numbers that were real close to 20,20,20. These are working very good, but it's a bit disconcerting why we have to be so far away from "stock".