10r80 Shift Character and TCC Lockup, "Drag Mode" in non-Drag Mode Car

[deanm11]

I am working on my "FBO" 2020 Mustang GT Base 10r80.

Base cars don't have drive mode so I attempted drag mode by specifying shift character of 2 across Sport/Track. The behavior I'm about to describe says otherwise, but now I'm thinking I may never get that setting in my non-drive mode car. So I may only have the three settings in the first row 'Normal' avaialable to me. The three columns 'Off/SST/LID' are described in the software as SST mode. I understand SST mode to be when you start paddling. Off would seem to be before you paddle. LID, I see some reference to 'Lever in Drive' but that doesn't actually pertain to SST mode (?)

The main line of inquiry I have is due to the fact that my first dyno made it clear that I was not achieving lockup on the dyno ( and thus likely getting 10-15hp low as measured.) I instructed the dyno owner to put selector in S and shift to 7th for the pull. I get the following percentages of actual speed compared to calculated theoretical full lockup from the dyno run:

RPM Calc Speed Actual Speed Ratio
3725 83.22305552 76.9 0.924
4670 104.3360186 96.2 0.922
5550 123.9967673 114.8 0.926
6257 139.7923915 130 0.930
6948 155.2305476 144.9 0.933
7160 159.9670007 149.5 0.935
7700 172.031551 163 0.948

On the street, I see what looks like a steady 97% ratio in one 3rd gear street log when in 'S' and about 98.5% ratio when in D, the latter based on several logs.

Is anyone able or willing to explain what parts of the shift character table I can utilize in my non-drive mode car?

What about whether shift character 1 or 2 is expected to not result in full lockup. My #s suggest perhaps a '2' is unlocked and '1' is half way to locked. If this is right, the tables that may control this certainly don't appear to be revealed to us.

Finally, is one able to make these cars dyno in D? Won't they always downshift on you or does pulling the dyno plug cause it not to do that?

My shift character tables, stock and tune are attached. Tune as of dyno attached. I have shift character maximum set to 2.

Thank you kindly.

[deanm11]

Updates based on testing:

I added TCC Status, TCC State Actual, TCC State Commanded, Trans Calculated Gear Ratio, Shift Scheduling State, SST Mode and Shift Character Desired.

I set both Normal and Sport/Track rows to all zeroes for Shift Character and ran a log of a short WOT 4th gear SST mode run in S.
Then I set the entire Sport/Track rows to 2s and did a similar log/run.

With the second calibration, as soon as shifting to 'S', I got Shift Character Desired changing from Base to 'Alt 2'. So at least on a base car, the Sport/Track row pertains to S selected on the shifter.
I still don't know what that leading 'Off' column means as to SST state. When Shift Scheduling state is Drive, SST Mode is always 'LID off'. When Shift Scheduling State is 'SST', SST Mode is always 'Active'

In both logs, when going WOT, The TCC is reported always as fully locked. (TCC Status="Fixed Lock", TCC State Commanded="Hard Lock" and TCC State Actual="Hard Lock")
So I believe now that shift characteristic doesn't affect TCC operation. Trans Calculated Gear Ratio in these 4th gear runs is always near exact 1.76 spec.

I do see, however, a few percent "slip" in actual speed vs. theoretical calculated speed. In other D runs on the street, I was at approx. 99% ratio. I'm seeing it about 97% in these two runs... once I'm out of WOT, I see actual speed to calculated ratio actually go slightly positive 101% or so... you can see after snapping throttle shut the rpms coming down even as the car continues to pick up a bit of speed.

Ok, there's a few percent of something going on that's not related to PCM command of the TCC at least. What I'm still working through is what I was seeing on the dyno. In the mid rpms, I was getting a 92.5% ratio. That's significant and quite a bit different that the street S runs here. There were 3 runs on the dyno - I rechecked my calculations ( I have the winpep files; It wont let me add '.drf' files here) and from run to run, I have 92.5% actual speed to theoretical for a broad band of rpm range. If the rpm signal were late, the speed mismatch would be in the other direction. I wonder if something else could be wrong with that dyno. The raw speed error is sorta stable, so the percentage shortfall reduces at higher rpm/speed. Can the dyno be setup in a way that it has the speed wrong ?

Dean

[paulsmithsr]

Good info

[deanm11]

I performed a further test in 7th gear, gear selector in S, with 'shift character 2. My actual to theoretical speed ratio at WOT averaged approx. 98.5% compared to the slower speed 4th gear runs posted above at more like 97.3%.

On this new 7th gear log, I newly added the Trans Input shaft and Trans output shaft, and TCC Speed ratio. The trans shaft relationship is consistent with the actual gear ratios, no issues there. TCC speed ratio is 0.999-1.000 during the test.

Again, on the dyno, I see something closer to 93%. I was not allowed to stay during the dyno runs.. I wonder if the car was not warmed up during the runs. 3 runs were performed and a few hp were picked up each time. If, as on the street, the TCC is commanded to be locked, input/output shaft speeds are good, this would leave possibility of some tire squat maybe?

Does anyone have some dynojet run files of their gen 3 coyote 10r80 mustang with rear gear and tire diameter for comparison ?

The "dyno plug" was disconnected when on the dyno. This should only affect stability/traction control but at some point I'll log a run that way. And maybe I'll try a run with the car half warmed up.

Otherwise: I will only go back to the dyno where a) I can stay and observe and b) I can have my laptop set up for a log