F2000? Looks like a local series? As I can actually see the pic you attached now I understand nothing. To me it looks like the only thing you would change by turning that "nut" is ride height. The only way to "adjust" preload withouth changing ride height would be to lenghten or shorten the stroke of the shock itself.
Potenziato: How old are those numbers? Are they from Ron himself? Looks like we will have something do discuss at the dinner table 1½ week from now because I totally agree with TS-turbo.
