Need help setting up MAF using STFT to adjust MAF

[Chalky]

I followed the tutorial. Problem is I don't rmember how to set up a MAP using STFT to adjust MAF tables. Can someone advise?

[Chalky]

Never mind. I got my MAp setup. Question I have now is the value I achieve for each frequency a multiplier or an add or subtracts from current values? I am assuming this values are multipliers from past experience but would like confirmation!

[mr.prick]

Yes.
Examples of STFT & LTFT BEN
"({SAE.SHRTFT1}+{SAE.SHRTFT2})/2/100+1"
"({SAE.LONGFT1}+{SAE.LONGFT2})/2/100+1"

[joecar]

Yes correct, in the form shown by mr.prick above, they are multipliers.

[Chalky]

OK. Where would I place your formula? If calc_pid, I woudl be lost. :)

I was just going to use driver side bank as it seems to run leanest anyway. Using boths banks together would be better of course.

[joecar]

OK. Where would I place your formula? If calc_pid, I woudl be lost. :)

I was just going to use driver side bank as it seems to run leanest anyway. Using boths banks together would be better of course.Post your calc_pids.txt file here, we'll edit it :)

[Chalky]

Here you go! Appreciate the help.

[joecar]

Quick questions:
- Do you have V1 or V2...?
- Do you want am LTFTBEN pid or a STFTBEN pid (using both banks, right...?)...?

[Chalky]

Joe:

V2. If only one option, use stft. If both, that is OK as well. Both banks please.

I used to have a calc_pid setup to meaasure RWHP/RWTQ. I believe it got overwritten. Did that calculation ever come to be valid or worthwhile?

[joecar]

dave,

V2, ok... another question: which wideband do you have...?

[Chalky]

PLX SMAFR and LC1

[joecar]

The calc pid to calculate RWHP is still there, you have to enter vehicle mass at File->Enter VIN.

The problem with this pid is that the LS1 PCM updates at only 10 frames/second... so the accuracy is limited by the time resolution... you can still use it for comparison as long as you can control the environment/conditions (e.g. same stretch of road/track, same time each day, in same direction); it tells you what HP is left over at the rear wheels to propel the vehicle (i.e. increase vehicle's speed) after all friction has been overcome.

The E38 ECM updates at 40 samples/second, so it will be better.

[joecar]

PLX SMAFR and LC1Does the PLX have serial comms for the V2 to read serial AFR/Lambda/EQR...?

Do you have null modem serial comms cables for both of them...?

Do you use them together at the same time, or do you use them separately...?

If both widebands provide serial AFR/Lambda/EQR, then we can use the EXT.WO2xxx pids.

[Chalky]

Sorry Joe, never saw the reply. I have always used the PLX but recently bought the LC1. My plans are to only use one at a time, just not sure which one. I ordered a serial cable for the LC1 I believe.

The PLX SMAFR was never factory developed for serial. Someone developed a serial conversion for the SMAFR but I never followed up on this conversion.

If troublesome, just setup the LC1. :)

[joecar]

Sorry Joe, never saw the reply. I have always used the PLX but recently bought the LC1. My plans are to only use one at a time, just not sure which one. I ordered a serial cable for the LC1 I believe.

The PLX SMAFR was never factory developed for serial. Someone developed a serial conversion for the SMAFR but I never followed up on this conversion.

If troublesome, just setup the LC1. :)Dave,

Another question: for your PLX, do you use analog AD1 on your V2...?

[joecar]

Does the PLX wideband assume 14.7 for stoich...?

[joecar]

Dave,

Here is your new calc_pids.txt file...

You will have to now log GM.EQIVRATIO;

The LC-1 will use the serial pids, and the PLX will use the analog pids.

So the BEN pid you use in a map is any one of (depending on what you're doing):
- WO2BEN (for LC-1)
- PLX_BEN (for PLX)
- LTFTBEN,
- STFTBEN.

Edit: deleted attachment, see new calc_pids.txt file two posts further down.

[joecar]

I haven't tested, so please give it a whirl, see if you can select the pids it mentions, and let me know.

[joecar]

Hi Dave, try this one, it has your PLX analog pids plus the Calc.VET/MAFT pids.

[joecar]

Dave, to adjust the MAF, do this:
- set your tune to disable dynamic air (i.e. disable it from reading the VE or VVE tables; it's different on an E38),
- use either wideband BEN and/or LTFT BEN to create a MAF correction BEN map,
- multiply the MAF correction BEN map into your MAF table,
- re-enable VE/VVE.

[Chalky]

Joe:

What parameter do I use to disable VVE? It looks like B8024/B8025 is equivalent to B0120 in LS1B but not sure.

[joecar]

I don't know E38...

[Chalky]

Pretty sure I have the right parameters. Thanks for the help with the calc_pids.

[joecar]

No worries :cheers:

if you need help in editing calc pids to suit E38 just let me know.