Weren't you changing props at Muncie this year? Like on Thursday afternoon when the density altitude seemed to get so high?
I changed noseweight mulitple times but I don't recall a prop. I *did* change from a heavily-chipped one (from digging up the grass at Woodland for the last few years) to a new one that had something like an airfoil at the tips. But they were both 12.5-3.75s. I do occasionally experiment around with the pitch but for whatever reason, this airplane wants 3.75 and is not nearly as solid on 3.9, no matter how hot it gets. the previous airplane liked 3.9 better. The only time I switch is at Tucson, were I go to 4.1 and also to YS20/20, just to get it back in a constant 4-stroke.
The noseweight was an interesting experiment for at least two reasons. The first is that I can tell a distinct difference between a small aluminum prop washer, a small steel prop washer, and a large steel prop washer, and between a steel nut with part of the spinner stud cut off, and a complete stud. Some of them only differ by 3-4 *grams* on a 62 ounce airplane.
The other thing (and I discovered this at Tucson, too, probably because it's extreme enough to be very distinct) is quite counter-intuitive - in the thin air, it wants *more noseweight* and whatever handle spacing increase is required to get the desired sensitivity. I can leave the CG alone, get the spacing increased to get the same overall sensitivity, but it seems to lighten up the control effort in the middle of the corners. To get that right again, I have to add a touch of noseweight and increase the spacing even more to compensate. It's a marked change at Tucson, and some of the fiddling I did at the NATs last year was to see of the same thing happened at Muncie. Sure enough, same effect, to a lesser degree. Came back here, had to take it back out.
BTW, both Howard and Jim Aron suggested that this is a "princess and the pea" effect, but I won down in Madera after changing from aluminum to steel small prop washer, so even if it's all in my head, it works. I think it's more a matter of having spent so much time with the airplane (the second and third airplanes fly nearly identically, and I have been flying them for close to 20 years) that I can pick up even a slight change, AND, I know exactly what it has to feel like to be competitive.
Brett