Very limited power from standstill. 2016 L96/E78 ECM/6L90e in '88 Truck

[JS264]

Engine:
Electronic throttle > Throttle area limits > Max % area vs RPM = Set entire table to 100%

Someone butchered your Airflow Cylinder Charge Temperature Bias table

Your timing tables are not good and are going to cause tons of KR and make it run real poochy. You have too much timing in the Base tables without zeroing out the adders and too much in areas even if they are zeroed.

Increase knock threshold by 1.5x through 4000RPM

Remove PE delays


Trans:
Stall TQ management = 6000/6000

TCC Limit > reduction = disabled

[sgtbilko]

The Airflow Cylinder Charge Temperature Bias table has never been touched. I dunno how they are butchered unless it's part of the changes that the gear wizard makes. Nonetheless I pulled up the original ECM read and copy/pasted all the values you mentioned except knock threshold; couldn't find that value.

[JS264]

Weird on that bias table. Knock threshold is under knock sensor tab and it has a separate table for each cylinder. Don't adjust that until you get your timing stuff figured out. You should probably just go back to stock timing tables and adjust the knock threshold, you'll have much better results.

[sgtbilko]

I did go back to stock timing tables along with the other items u mentioned but haven't written to ECM yet. Found knock threshold, thanks.

[JS264]

Post up your latest tune. I'll do some quick tweaks on it for you if you want.

[sgtbilko]

ok will do that. gotta knock out a couple errands. about to write the tune now. thanks

[sgtbilko]

read before 20190727 HPT JS264 changes all.hpt
20190727 HPT JS264 changes all.hpt
20190725 running smooth DTCs off.hpl
JS264 changes a couple hiccups A.hpl

Made the changes you suggested. Attached before/after tunes and logs.

[JS264]

What hiccups did you have with those changes?

[sgtbilko]

a couple stumble/backfire going stabbing the throttle from cruise. 1st log around 4:45ish and second log around 9:00 or 9:15ish.

[JS264]

Did you tune the maf/vve? If not, it'll really show up the flaws since the throttle can open farther faster and the O2s can't keep up/pe commanded doesn't match actual.

[sgtbilko]

No idea how

[5FDP]

If you made the intake size the same as the factory equipped truck it wouldn't really require any huge changes to the airflow model. Then it would only be a stock engine with some exhaust work.


The more I read about the E78 computer, the more I understand why people hate it and use the earlier E38 computer.

[sgtbilko]

Intake is 4" cold air, so yes it's larger.

[JS264]

Step one for you is tune your maf/vve.


E78 isn't too much harder than the E38 on the V8 platform imo, I've done a bunch of both and I'm running my turbo 6.0l on the E78. Just a bummer there's no 2 bar OS for it but it works well with boost in open loop.

[sgtbilko]

I have no idea how to tune MAF/VVE. I guess I'll be doing some more reading. I have the MAF Calibration/Airflow vs Frequency multiplied. With the "MAF calibration restrictor" installed in the MAF tube the stock needs multiplied by 1.2, without restrictor it needs a lot more to get to the stock requested 14.8 AFR and that's still with a lot of LTFT. Something Don't seem right about all that.

[LittleBlue]

Thanks for the info on e78 not having 2 bar option. I have been trying to find out how to switch to 2 bar the last few days.

[8850]

I have no idea how to tune MAF/VVE. I guess I'll be doing some more reading. I have the MAF Calibration/Airflow vs Frequency multiplied. With the "MAF calibration restrictor" installed in the MAF tube the stock needs multiplied by 1.2, without restrictor it needs a lot more to get to the stock requested 14.8 AFR and that's still with a lot of LTFT. Something Don't seem right about all that.

https://forum.hptuners.com/showthrea...621#post416621

After you get your configuration and log then to correct your table Open your file. Change the drop down box on the left to manifold switch to open. The default table is Closed. Open the log file. Click VE vs. Fuel Trims. Highlight and copy the graph. Go back to your file to the VVE editor table, highlight and right click paste special, then click multiply by %. You want to get all the cells you can but you can manually change some cells if there are ones you didn't get much data. If your log represents the way your normally drive then you should have most of the cells corrected. Finally click "calculate coefficients" over on the left. It will update the table and you are done after saving the file. You should see some values in the table change when you click calculate coefficients.

[JS264]

Thanks for the info on e78 not having 2 bar option. I have been trying to find out how to switch to 2 bar the last few days.

It takes a while to get the tune setup to compensate for temp changes but you can scale the VVE tables/MAF and use Airflow Gain to do your boost enrichment by MAP and activate your PE with requested torque at 13.8:1a/f. Its buttery smooth, but you must use open loop all the time or that table is not referenced. I hated the way mine ran with closed loop/pe dump...

[sgtbilko]

20190728 LTFT STFT VVE.hpt

20190728 LTFT STFT VVE LOG A.hpl

I followed the guide you linked, attached tune and log files.

Something ain't right about the graph. It's logging only the 1.02 line so I cut the trip short. Could that have something to do with Kpa vs PSI?

It seems to be running great right now, with good AFR on wideband and plenty power. Yesterday I changed the MAF sensor and tube because the old tube's mount gasket was questionable.
That being said, would still like to be sure MAF is reading correctly and get VVE set up best I can, but stuck with only 1 line and doubting it's right.

[sgtbilko]

I got the graph figured out; had to log "MAP/Baro (Pressure Ratio)" instead of "Manifold Absolute Pressure".