Yes, thank you for clarifying what I have said twice now.

In my particular case this is what worked best for me, as I did not have data for my MAF housing or my injectors beyond a rough estimate of what the injectors flowed. Yes, I should have done one at a time, but I still stand by this method of forcing AFRs to confirm where inaccuracies are hiding, particularly since we can't rely entirely on seeing if ps_w==pvdkds_w to verify MAF accuracy at light load, especially when we may also be fighting an unknown TVUB in these light load areas.

Shit, don't take this the wrong way but I could even argue your method in the OP is, the perfect example of how not to tune since you should just have correct injector data from the manufacturer instead of making assumptions, but that would be retarded and completely ignoring the fact that this is tuning and that there will always be areas that need to be tweaked here and there to get things right.

I appreciate your technical posts prj, and I don't disrespect your insight because you don't say what I want to hear. I suppose we're starting to really go off tangent to the OP, but would you argue that relying on ps_w for MAF tuning is a poor practice? I will admit that my understanding of the load model isn't perfect, but as I understand it, (rlroh_w - rl_w) -> intake manifold integrator magic <-> ps_w -> VE model magic -> rl_w, where, generally speaking, rl_w will be pretty close to rlroh_w in steady state (this is why you say ps_w is partly irrelevant).

In my case, I did not tune relying on STFT+LTFT, rather forcing lambda to a specified value (typically 0.99 or 0.90) and logging lamsbg_w, actual lambda (thru the downstream ADC), ps_w, uhfm_w, nmot, and with enough data from street driving I was able to see where problem areas are hiding, either in the MAF or injector data - the key here being that errors that show up when lamsbg_w gets changed implies a problem in the injector data, while problems that persist implies a problem in the MAF data. The end result is that my ps_w is very close to actual manifold pressure, and whatever lambda I request is the lambda I get. My STFT+LTFT stays within 5% overall in closed loop, which I consider good enough considering how pump gas can vary - maybe this might not be the case on a very high powered car where going 5% lean could result in instant engine deconstruction.

I am a mechanic by trade and do not have access to a dyno or any testing equipment, and this was done some time ago as my first hands on tuning experience, using injectors I got for free and a MAF housing I paid something like $5 for off a Ford F250. Would I do it this way again? No, unless I wanted to double check a tune as it's just about complete. Do I think this could go wrong and give you garbage data? Yes, probably. When I do my turbo ford I do plan on actually testing the injectors I use to get a good baseline for what injector breakpoint, high/low slopes, offset, and all associated pressure compensations before installing them since figuring out injector data from scratch on the car sucks no matter how you do it.

Thanks a lot prj.
It helps a lot,good luck with your next life.

Definitely not.

Does this assume that the load is directly reflected in the changes in battery voltage? I must be stupid but I don't see any point in this, very bad way to adjust the injectors. Could you please enlighten me.

What I would do is modify the voltage regulator of the charger and add a potentiometer to it and adjust the tvub with it.