Does PE mode affect tuning VE table

[Bill00Form]

When tuning the VE table don't you need to account for the when the pe mode is enabled? I thought all tuning was in reference to stoich (14.63) Just wondered how you determine when pe mode is enabled and do you need apply a factor to your table. Thanks

[Jester]

I use Lambda when logging my BEN, so if PE is active and I am commanding 12.55 and my WB02 is logging 12.55 my lambda in my BEN map will be 1 regardless. You could also filter out PE data from the BEN map. I'm not the best at explaining things by writing them, hope you understand what I am getting at.

[Chevy366]

The old VE tuning you would use 14.7 for all the tuning of the VE so you would put 14.7 in the PE to keep it from influencing the VE while tuning. This is what I do, VE table is right on then when you add PE to the mix it is usually spot on too. I think now with the AutoVE and AutoMAF you don't even bother anymore.

[Jester]

The old VE tuning you would use 14.7 for all the tuning of the VE so you would put 14.7 in the PE to keep it from influencing the VE while tuning. This is what I do, VE table is right on then when you add PE to the mix it is usually spot on too. I think now with the AutoVE and AutoMAF you don't even bother anymore.

Yes that works too but I find it a bit unsafe once getting in to higher rpm and load.

[joecar]

When tuning the VE table don't you need to account for the when the pe mode is enabled? I thought all tuning was in reference to stoich (14.63) Just wondered how you determine when pe mode is enabled and do you need apply a factor to your table. Thanks

No.

The commanded EQR pid (GM.EQIVRATIO) shows the current commanded EQR (e.g. if PE table is commanding EQR 1.175, then that pid will show EQR 1.175).

Same with the AFR pid (but please don't use this pid for tuning).

You don't need to determine when PE activates, and you don't need to adjust for it.


In general, from the active tables, the PCM selects the richest (at the current operating cell) and commands this EQR, and emits this value on the commanded EQR pid.

[joecar]

Setting PE table to stoich (or otherwise preventing PE) is damaging to your engine.

[Chevy366]

I quote from old AutoVE tutorial, page #5 -- Open calibration {B3618} "PE Modifier Based on RPM" Select all cells by clicking in the extreme top-left, gray cell.
If the calibration is displayed as EQ Ratio then enter 1.0 into the Adjust text box and click the [#] button to set all values to 1.0 EQ Ratio.
If calibration is displayed as AFR then enter 14.63 into the Adjust text box and click the [#] button to set all to 14.63 AFR.
If this is incorrect, please advise and have corrected.
Have used this several times and it works without incident.
Theory was and I guess has changed since then, that PE wasn't needed to adjust VE to BEN factor 1.

[picnic_george]

2 different ways of doing things. I've done it with disabling PE/setting companded where I want it, and leaving commanded alone and setting PE where I wanted it. I've not had issues doing either. The point is to get to your VE table correct, and if all your other data is correct(injector) and your actual AFR is the same as your PCM commanded AFR then you're good.

[joecar]

I quote from old AutoVE tutorial, page #5 -- Open calibration {B3618} "PE Modifier Based on RPM" Select all cells by clicking in the extreme top-left, gray cell.
If the calibration is displayed as EQ Ratio then enter 1.0 into the Adjust text box and click the [#] button to set all values to 1.0 EQ Ratio.
If calibration is displayed as AFR then enter 14.63 into the Adjust text box and click the [#] button to set all to 14.63 AFR.
If this is incorrect, please advise and have corrected.
Have used this several times and it works without incident.
Theory was and I guess has changed since then, that PE wasn't needed to adjust VE to BEN factor 1.

Yes, that is incorrect... AutoVE has long since been modified to allow PE mode (whether documented or not).

Works ok if you keep engine load light... but then how do you tune for high load (WOT) or even medium load...?

Theory was that the transition to PE introduced some inaccuracy (wideband being downstream sees the transition after some time delay)... but since the PE transition coincides with throttle transition, the transient filter removes the PE transition.

[Jester]

I quote from old AutoVE tutorial, page #5 -- Open calibration {B3618} "PE Modifier Based on RPM" Select all cells by clicking in the extreme top-left, gray cell.
If the calibration is displayed as EQ Ratio then enter 1.0 into the Adjust text box and click the [#] button to set all values to 1.0 EQ Ratio.
If calibration is displayed as AFR then enter 14.63 into the Adjust text box and click the [#] button to set all to 14.63 AFR.
If this is incorrect, please advise and have corrected.
Have used this several times and it works without incident.
Theory was and I guess has changed since then, that PE wasn't needed to adjust VE to BEN factor 1.

Jeepuz, didn't know that was in a tutorial, nasty.

@Bill00Form - Have we helped or made things worse in your understanding?