2020 Mustang GT 10r80 FBO+E85: Odd Commanded WOT Lamda + Torque Mgmt on Shifts

I've got a "full bolt-on" 2020 Mustang GT. Full headers with cats, exhaust, Steeda closed air box, ported intake and TB. Dedicated "E85" though the tune is calibrated to the winter blend tested ~71% fuel I could source. The car is super strong and I think I have a shot at a 10sec timeslip. No option car with about 150lbs weight reduction.

I just put my torque/inverse tables and throttle body data back to bone stock. I thought I was improving things where the opposite was clearly the case. The car feels fantastic and the data generally looks good.

I have an air straightener honeycomb to help the "race only" Steeda MAF housing get a clean signal and I do think it is working well. Since going E85 and/or the weather warming up, my STFT (I have LTFT disabled), I do have a few percent negative trims but I'm not worrying about that right yet.

In recent testing, I realized torque management was still pulling significant power on shifts. (in 'D' / tuned to shift character '1'. My base car doesn't have drive modes) I discovered the 33458 'Spark torque reduction' shift modulation where I set to 1 to remove spark retard on shifts. Not only does it still seem to retard spark, it seems to have invoked fuel enleanment control, even after setting 'Shift modulation' to 0 under 44775 Fuel Cut Torque Ratio vs. Requestor.

Tune and log of various part-throttle and WOT driving is attached. I have three questions, if anyone is willing to help.

1. I'm observing more times than seems reasonable that my 'WB EQ Ratio Bank 1' is going way lean (well over 1, sometimes apparently pegged at 1.998884) Almost always it seems related to either the trans shift mod control using enleanment despite my thinking I've removed it's capability, or a decel situation. But even at some other spots it seems to report numbers well above 1. Any ideas?

2. Any direction on how to properly remove ability of Trans Shift Modulation to cut power via both spark and fuel ?

3. WOT fueling: When Fuel Source is solidly in 'Power Demand Enrich', while my tables are no leaner than 0.85, and yet Equivalency Ratio commanded is hovering around 0.90 more often than near the 0.85 in my WOT Lamda tables. Any ideas ?

Thank you.

Dean

I do now see that I was going wrong with the 44775 fuel cut. I set that back up to 1. I'll retest.

To the member who for the second time today offered to sell me a tune and "Fix all my issues" And also after asking for my log and tune in posts on the board here - that's really not nice. I don't think there's much missing in my tune here.

To all those that collaborate, and more importantly educate those less initiated in tuning here, bravo, thank you very much.

2. You are commanding torque reduction on the shifts in the tune. At some point it's going to do what it needs to regardless of your settings, to achieve this goal. If you don't want it to pull power, then up the torque values I suppose.

3. WOT fueling. I believe the explanation for this is: your fueling is rich and trims are pulling fuel. As a result the car is commanding leaner (0.90) to meet the WOT fueling values in the tune (~.85). In other words when you get your fueling dialed in the commanded vs actual will be much closer...

People soliciting tunes here, I'm not surprised. Everybody trying to make a buck lol.

1.&2. Raise ECT temperature based fuel cutoff from 7350 to 7600 or higher so you are not hitting the RPM limiter on shifts.


Attachment 108694

3. use this channel list, and dial in your MAF curve to under 2% error. Everything above 40lb/min you are about 4-5% rich. Need more data, and a better log. you want to put it in 6th and go from 3000-7900RPM. This will be like a 40-130MPH pull in one gear. it will take 10-15 seconds giving the scanner lots of time to collect data. Not the safest thing to do on most public roads. you could also do 4th from 20-100MPH, and probably be fine working with that.

You definitely want to watch load. For NA if its going higher than 1.05 thats probably not right. if it doesn't peak around 4750-5500 and slowly drop off after that, somethings probably not right. It a way to independently check the plausibility of the MAF values the car is reporting instead of just taking all fuel error and putting it into the transfer function. A chart of your load during a WOT pull, should resemble the shape of the torque line on a dyno graph. Both peaking at the same RPM.

Attachment 108695

blackbolt22, murfie, thank you very much for the help.

Yes! Duh, I've been lazy about getting MAF back in line and the commanded lamda is what the ecu is doing.
I actually may have enough logs from previous logs since I let the MAF go off to get that back within 1-2%. I'll start with what I've got and can probably get it near perfect with one test.

mufie, I'm trying to understand your comment about load. I've logged absolute load in the past and at WOT especially when temps were either side of 30 degrees, I would get load between 105-110 from 4000rpm on up. (I've not been logging as many channels as previously in order to get good polling and also not using interpolated data) Would I watch the 'Air Load' ? Was this a more general comment to watch for it or do you have a particular concern in my case? I have moved my torque/inverse tables back to stock; I could consider tuning them at least from the mid-range of load higher. I'm sure with all my mods and E85 they could stand adjustment. But I'll get the MAF dialed and re-check how my shifts are going first.

Thanks for taking the time to help.

Air Load is correct and what these cars really use with the ETC model. That's what I use. For the most part it's the decimal value of absolute load.

Murfie has attached the .xml file for you to log the good channels. Load that up in the scanner and go datalog with that :)

I used your MAF value to calculate load and saw it coming out to 1.05-1.17. That's much too high for NA. The 5% rich is causing some of it, but not all. Maybe excellent DA but I don't think you would even see 1.12 in the best DA.

What injectors and fuel system are you using? That's the other half of the air / fuel ratio where the error could be and the MAF is making up for it.

I'm seeing a bit wrong with this file and concerning.

Why did you increase the MBT tables? E85 would be a lower MBT usally 10% lower is a good starting power with out a dyno to verify.

Quote:

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Originally Posted by pwnall1337

I'm seeing a bit wrong with this file and concerning.

Why did you increase the MBT tables? E85 would be a lower MBT usally 10% lower is a good starting power with out a dyno to verify.

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Ethanol(0.78945 g/cm3) is denser than both octane(0.703 g/cm3) and heptane(0.6795 g/cm3), the two main ingredients in gasoline. Normally denser means slower combustion reaction. Slower means more lead time in ignition to match the reactions cylinder pressure influence with the pistons cylinder pressure influence at TDC.

This is very critical, AFR is king, the engine will not run if the AFR is not with in a certain range. Assuming the same stoich lambda values for the different concentrations in a fuels ethanol content (this accounts for the extra O in the ethanol), the higher the ethanol content, the denser the fuel will be, the more advanced MBT should be. Its what general chemistry thought me, and why I tell people they can increase MBT some when moving to a higher ethanol concentration. A fuels specific gravity is a good indicator of how much spark advance it is going to need. Some race fuels have a chemically built in catalyst, but they are exceptions not examples. As far as I know ethanol alone is not one of them.

The other major component to flame speed is the temperature of the flame. Ethanol releases just under 13000 BTU per pound, while heptane and octane are around 19000 BTU per pound, so the flame also gets colder with higher ethanol content. You are just adding 40% more ethanol and getting about the same total BTU's released.

The major tuners of the gen 2 coyote engine increase the MBT spark advance from ~26-28* to ~29-31* when switching from E10 to E85. For empirical evidence.

Quote:

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Originally Posted by murfie

I used your MAF value to calculate load and saw it coming out to 1.05-1.17. That's much too high for NA. The 5% rich is causing some of it, but not all. Maybe excellent DA but I don't think you would even see 1.12 in the best DA.

What injectors and fuel system are you using? That's the other half of the air / fuel ratio where the error could be and the MAF is making up for it.

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Murfie, thank you for further observations.. I somehow didn't get a notice update about further posts to this thread. I do plan to get a fresh log soon and will use your channels configuration.

The air is pretty darn good with these cold temps, I'm still a little slow to indict loads near or a bit above 1.05 at least. I've gone back to stock torque/inverse tables so we'll see how the load looks; may be able to get a nice closed course log overnight.

To your question - bone stock injectors and fuel system.

Here's a log with the current tune, using Murfie's config. On very brief WOT/near WOT in there plus a medium one. I had retuned MAF but I still seem to have a bit of negative trims. Still some peak air loads near 1.10. About 48 degrees ambient temp. The car is running great across the board at this time. Got rained out at the track on Friday night. Car has zero passes on it. In very good air, I think a 10.99 is possible, assuming a sub 1.80 60ft on my drag radials.

You could try coping the alt 2 torque modulation tables of Alt 2 to Alt 1. Or just make the high RPM high torque area 738 ftlbs.

D uses base

S uses Alt1, maybe its not actually going to alt 2, you have to add the channel "shift character desired" to really see.

The good news is it didn't cut throttle or fuel on the shift.

Attachment 109038

Quote:

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Originally Posted by murfie

You could try coping the alt 2 torque modulation tables of Alt 2 to Alt 1. Or just make the high RPM high torque area 738 ftlbs.

D uses base

S uses Alt1, maybe its not actually going to alt 2, you have to add the channel "shift character desired" to really see.

The good news is it didn't cut throttle or fuel on the shift.

Attachment 109038

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Thank you murfie. I'm going to have to get a log in S at some point. My previous testing proved (with that shift character log) that the attached setup ensures I am shift character 2 when in S. (I have a non-drive modes car) So I believe with my tune, S will use
Alt 2, assuming the calibration will go there when in Shift character 2.

Finally, some good new logs.

Closed course, one in D, one in S. Shift character 2 in S, 1 in D.

3 tenths faster in S 60-130. Very nice cool air but 15mph winds out at the time. Very pleased with the tune and performance. 7.81 60-130. Course is not flat but if anything net uphill.

Tune file, new name but only change was the RPM/speed parameter to try to correct my speedo. I notice I'm reading a few % high.