What kind of changes are needed to run speed density

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Originally Posted by Sid447

Learn something everyday!

I didn't know about these (I'm M6) are these changed to Yes? Maybe there's a thread explaining this a bit more?

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Change these to No to disable max line pressure.

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Originally Posted by SSpdDmon

SD changes required:

Flip MAF Fail frequencies: C2901 & C2904 (low becomes high and high becomes low)
Change Fail Limits to 1: C2903 & C2906
Copy High Octane Spark to Low Octane table
Change MIL Enablers C6002: P0101, P0102, P0103 = No MIL
(Don't change Processing Enablers)

That will put you in SD.

If you were going to tune with a WBO2, you would also want to go open loop.

Open loop tuning changes required:

Disable LTFTs - B3801
Disable STFTs - B4205 (set all to 283*F)
Adjust Commanded Fuel in Open Loop table - B3605 (set all rows 158*F and greater to stoich)
Adjust PE Based on RPM table - B3618 (set as desired for WOT)
Adjust PE Mode Enable - B3616 (adjust as desired by TP% & RPM when you want PE to activate)
Disable DFCO - B3313 & B3308 (set to 283*F)
Disable Cat. Overtemp Protection: B0701

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WHY would you not disable processing enablers??? Please, I have trouble popping codes for mil"s I have set to No mil

If you disable the processing enablers, then the MAF DTC's will not be triggered...

If the PCM does not see a MAF DTC, then it won't go to SD (VE only) mode...


i.e. when the PCM sees a MAF DTC, it fails over to SD mode.


i.e. the presence of P0101, P0102, P0103 signifies that the PCM is now running is SD mode.

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This is all we have so far: showthread.php?t=10773

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Change these to No to disable max line pressure.

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Thanks "Joecar" & "5.7ute."

:cheers:

What is GM's reasoning for the MAF tied to the transmission pressures?

I don't see the need. Isn't TPS fine for it? Or does it really use Calc Load and that is thrown off without a MAF so it goes max hard to make up for the lost value?

If airmass calculation is low, then commanded transmission pressure will be low, this allows clutches/bands to slip during high torque.


airmass -> calculated torque -> commanded line pressure

Are there any tables for it? On my L67 (3800 SC) I am on MAFless and having no problems with the trans with no MAF. All I can do is unplug the MAF and set the MAF Fail Low freq to 0.

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Originally Posted by joecar

If airmass calculation is low, then commanded transmission pressure will be low, this allows clutches/bands to slip during high torque.


airmass -> calculated torque -> commanded line pressure

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Look for P0101,2,3 in tables E010x.

Some vehicles have those set to No

I set mine to NO when I killed off the MAF. It was bad and I figured it was a good time to tune without it and see.

Only problem I have is low airflow at low speed it stalls sometimes. I can't figure out what is up, even when driving, it almost seems like DFCO is set to aggressively. But it is set stock.

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Originally Posted by joecar

Look for P0101,2,3 in tables E010x.

Some vehicles have those set to No

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Quote:

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Originally Posted by SSpdDmon

SD changes required:

Flip MAF Fail frequencies: C2901 & C2904 (low becomes high and high becomes low)
Change Fail Limits to 1: C2903 & C2906
Copy High Octane Spark to Low Octane table
Change MIL Enablers C6002: P0101, P0102, P0103 = No MIL
(Don't change Processing Enablers)

That will put you in SD.

If you were going to tune with a WBO2, you would also want to go open loop.

Open loop tuning changes required:

Disable LTFTs - B3801
Disable STFTs - B4205 (set all to 283*F)
Adjust Commanded Fuel in Open Loop table - B3605 (set all rows 158*F and greater to stoich)
Adjust PE Based on RPM table - B3618 (set as desired for WOT)
Adjust PE Mode Enable - B3616 (adjust as desired by TP% & RPM when you want PE to activate)
Disable DFCO - B3313 & B3308 (set to 283*F)
Disable Cat. Overtemp Protection: B0701

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could you illustrate this point
because in AutoVE tuning tutorial they did not say any thing about MAF low frequency