As you can see, I-Max is completely inappropriate for requested boost. It should (roughly) be the dc required to make requested at every point. Req boost is rising until 3000rpm, but i-max does the opposite. Then it starts tapering, but I-max is increasing.

So:

By 2600 rpm, we should be seeing requested boost, which is around 16psi.

If you look later in the graph (at 3100rpm) , 16psi requires around 82-83 wgc. At 2600, I-max is around 82, and given that Q2 is going to result in at least -3 or -4, we'll probably need an I-Max of around 85-86 at 2600 rpm.

By the time req boost is at its max (3000rpm), I-max is almost at its minimum! Given that we probably need at least 87ish dc to make 16 psi, I-max should be rising to match the requested boost.

Also, the requested boost should really not be increasing during late spool, it should really be flat (or tapering). This will make tuning the PID easier (since I will accumlate faster, it is more likely to follow i-max).

Finally, I have omitted linearization for the time being since it only complicates the discussion: suffice it to say the purpose is to have a normalized dc->actual boost curve.

That is to say, you need more DC up top for a given boost, so LDRL should be tuned such that a COMPLETELY flat pre-lin DC should result in a post-lin DC that is increasing sufficiently to keep the boost at a given PSI.

Ideally, when tuning i-max, you should be thinking about corresponding changes in LDRL accordingly. If you are finding you are having to have an increasing i-max to keep up with a flat boost request, instead of having a rising i-max, consider a rising LDRL instead.

Thanks for confirming my hunch that the DIMX still needed some work.

I also noticed, though have not posted a chart of it, that my desired AFR is going richer than the other cars.  That seems strange because I have gone back to the S4 EGT sensors and returned the TABGBTS and KFLBTS to the stock values.

Nef_N75-2 data file

A couple of things I've noticed differing between the Hitachi and Bosch bins:

Variable/Hitachi Value/Bosch Value

CLAATR / 19 / 0
CLAATR2 / 19 / 0
CLAATS / 19 / 0
CLAATS2 / 19 / 0
TABGSS / 979 / 1229
TABGSS2 / 979 / 1229

Should they be different?

There are so many variables that go into the BTS fueling (and the EGT model) that I am not surprised. You'd have to flatten them all out (or log a lot more stuff) to nail down the root cause. Also, I don't think the enrichment you are seeing is from ATR anyway, just BTS from modeled EGT.

By the time ATR triggers, it is WAY too late...

BTW I don't see anything wrong with letting the stock BTS do it's thing. if you want, you can prevent it from going much below 0.7 by flattening the bottom of the BTS map, but I wouldn't recommend it. You can also numb DLBTS (set to 0 <=6%) if you want.

Then this is not a stock bin.