The Bishop: I read your reply a week ago and should have wrote back earlier. I remember thinking something like that back when I was doing more autocross, so for the past 4 years or so I always race with a full tank of fuel to prevent any slosh or starving the pump. But also , I am with you about the possibility of g-forces working against the direction of fuel flow forward. Glad you brought it back into the thoughts for me to test out.
I made some great headway with sorting this out, I knew something had to be in the datalogs. If anyone remembers, for at least a year I was having all sorts of wacky/useless datalogs or missing and corrupted files. I feel that that slowed me down, and turned me in the wrong direction. I was following the AFR numbers that I was seeing on the gauges, but anyways here we are. I noticed that on the recent datalogs that I now can save and review successfully, there was a "Rich Cutoff" parameter that is built into the nitrous log-viewing screens. Despite the areas where the AFR numbers would go sky-high lean, this is when the "rich cut-off" would trigger and shut the nitrous off. I also took note of what townsend and Thirdgen.org member skinny have mentioned.
Turns out it is simply just overfueling because of mismatched jetting. I tested a chart that townsend sent me and changed my "150 shot" from a .059 nitrous with a.030 fuel, to be a .059 nitrous with a .027 fuel jet and it got way better. Next pass I went with a .062 nitrous and .027 fuel. Got better again. Next pass I was better yet and it was a .064 nitrous and .027 fuel. The mph kept improving, back to where it used to be over a year ago.
This all still sounds confusing to me, but the theory behind what I understand this issue to be, is that the fueling was indeed rich, but to the point where the oxygen sensors can not read correctly because of excess unburnt fuel and oxygen in the downstream exhaust. I wasn't aware of this until post #493 here :
https://www.thirdgen.org/forums/tech...nstall-10.html . I guess I still don't yet get it completely, but at the track rental my new jetting gained me back good timeslips.