With all the other drama - I forgot to post here yesterday - I need to lay this out so I don't forget.
I finally resolved the drivability problems I had been having that made the car less than pleasant to drive unless under heavy throttle. Part throttle (partial tip-in, maybe 2-5% open) can result in engine surge and wild AFR (lean) sweep. Feels like driving with someone who doesn't know how to operate a clutch, if you know what I mean.
I've been back & forth in the K-Tuner software forum - not much help there at all, so I posted my problem on the K20a.org forum, and got a few helpful suggestions as to where to look when logging for meaningful interpretation of the data flow. So, the bottom line there was that I needed to get some fresh datalogs, from a cold start through warmup. They offered to review the logs & help me figure out where to go from there.
I drove the car to work yesterday morning - 15-20min drive, mix of local & highway driving so perfect for a comprehensive driving log. It did pour with rain in the north of the county where my school is, so I was able to check that I am leak free around the doors and targa
What I noticed while driving (I glanced at the main screen to make sure the recording was staying active) that displayed throttle % was not matching my pedal position in that low tip-in range - it seemed to be lagging behind the actual. Anyway, I completed the logs, did what I needed to do at school, and went home to get on with the iLearning school day. As an aside, when I left school I noted that the battery voltage was low & cranked a little slow. I realized the battery is probably 7 years old now.
After work, I went & bought a new Interstate M-24F in town, and I decided before I sent in the datalogs for review, I'd better check the TPS setting relative to butterfly opening/pedal position, so I hooked up the laptop & checked it from the pedal, and from the bobbin. In both cases there was a lag - in other words, the throttle plate was open several degrees before it registered. It seemed to me that that would explain most if not all the drivability issues. It was puzzling, as I had gone over the butterfly & TPS settings several times.
There is no way to get to the TPS without removing the TB
After removing the TB, I had to remove the TPS & K-Tuned adaptor plate & rework the plate mount again - as an addtional complication, the way K-Tuned mounted this (below) the TPS was not in the proper range. The new problem was that in the modified position, I had not allowed for a wide enough adjustment window, and it was all the way up against the stop. I had to dremel the slot to allow the mount plate to rotate another few degrees CCW, which then moved the TPS mount screws into the middle of the adjustment range. With that, I was able to center the TPS on the shaft, and get it adjusted so that the butterfly angle registered in the software immediately, with no lag or disconnect.
(Old pics, to illustrate TPS mounting)
Put it back together, double checked the butterfly repsonse from the bobbin & at the pedal, all good. I took it for a drive to check if that resolved the problem, which it certainly seemed to have done. Then I drove it off the road