Tuning WOT

[domestic rice]

I have seen that you get the VE and MAF tuned and then adjust the PE to what (dial in) for WOT. Then I seen where you just set the PE to what you want and adjust the VE or MAF for the fine tuning. Is there a better method or is it all just what the tuner prefers to do?

[eficalibrator]

If you want it to be consistent (even as the weather or total airflow changes), then you'll start with GOOD injector data, then set your target A/F once and adjust the air model(s) to make your delivered A/F match the target.

If you adjust the target ratio (PE multiplier) to something other than the ratio you really want (probably because injector, MAF or VE is wrong), you will get ONE case where the car runs as predicted. But... once weather or total airflow changes, you'll see that yuo don't have control of AFR any more. Good calibrators generally won't do this.

[blownbluez06]

I have seen that you get the VE and MAF tuned and then adjust the PE to what (dial in) for WOT. Then I seen where you just set the PE to what you want and adjust the VE or MAF for the fine tuning. Is there a better method or is it all just what the tuner prefers to do?

I dial in the the VE and MAF everywhere except WOT. I predict fuel at WOT on the conservative, rich side, enter the mathematically desired AFR in the PE table and work my way up in RPM through multiple WOT pulls as I continue to adjust and predict.
As mentioned above, it's always wise to start with the proper foundation before building your house on it.

[vette_c6]

i would tune the MAF and the VE ,, until i get them good
thet i set my Command for the AFR ,,
if i saw an error in the command ,,means i havent tuneds right ,, so i start back to the maf or the VE

[gn2beatu]

Do what eficalibrator said, not what vette_C6 said. eficalbrator said to set the A/F and PE to what you want, then tune the VE/MAF.

[01ssreda4]

Not to high-jack but when going WOT on VE only tuning do you enable PE or leave it off and stick with your non-PE AFR during the run?

[eficalibrator]

PE should be able to work correctly regardless of whether the airflow is coming from a MAF, VE model, or blended model.

[LSxpwrdZ]

It's pretty easy guys. You have commanded lambda and actual lambda. The VE and MAF are just the tables you adjust to make commanded and actual equal. PE or OLFA are commanded lambda tables that are just what they describe.... your target lambda/eq/afr. If pe enables and it is richer than any of the other commanded tables then it will command that value and your airflow tables will need to be adjusted to make the resultant wideband reading match what is commanded.

[vette_c6]

PE should be able to work correctly regardless of whether the airflow is coming from a MAF, VE model, or blended model.

would you mind explaining for
when i command the AFR to be 12.5

and when i run it in dyno ,, i see 13.2 or 12.0

what could couse that ?
i hope you share your experience with us

[LSxpwrdZ]

That's where tuning comes in. Just cause you command it doesn't mean it's actually going to just up and produce that afr. Once you are commanding the afr you desire you then calibrate the VE or MAF to reflect the commanded afr.

[MMGT1]

I think what he's asking there is; "why he makes one run and it produced an AFR of 13.2 then without any changes to the tune it produces a result of 12.0 in the next run". Sounds like the adder tables are comming into play. look at the adder tables that reference IAT and coolant temp. I would guess you'll find your answer there. Again though, as Greg said, are you sure your injector data is correct?

[Iam Broke]

Could it be going into Cat Overtemp protection richening it up?

[NBMLS2TA]

Also, if you are in closed loop and your LTFT are out of whack when you enter PE mode won't that affect the PE Multiplier? I recall reading that if your LTFTs are not near or at 0 when you enter PE, whatever the LTFT is doing (adding or subtracting) will be carried over into PE WOT....not sure but thought I may suggest that as a reason for the large swings in AFR during PE

[domestic rice]

I am done with the wot tuning till I get a new sensor. I don't trust this one. I believe that has been half my problem since the start. When I get a new one I'm planning to start from scratch and fine tune this. It is actually running decent now, but had to go back to ol school tuning with fuel trims once I figured my wb02 is FOS.

[domestic rice]

I think what he's asking there is; "why he makes one run and it produced an AFR of 13.2 then without any changes to the tune it produces a result of 12.0 in the next run". Sounds like the adder tables are comming into play. look at the adder tables that reference IAT and coolant temp. I would guess you'll find your answer there. Again though, as Greg said, are you sure your injector data is correct?

This is a problem i am running into now. my "commanded" is dead on with the exception of 5200 and 5600 rpm area of WOT. I am commanding 12.8 across the board, yet the commanded histo is showing 11.7 and 12.08. My OLF/A is commanding 1 in the ECT im running. Not running closed loop at all so cant be anythign there. What else could be screwing with this giving me the wrong commanded airflow?

[LSxpwrdZ]

Cat over temp. Turn it off or reduce the enrichment to equal or below your PE to keep it from going too rich.

[domestic rice]

Cat over temp. Turn it off or reduce the enrichment to equal or below your PE to keep it from going too rich.

That did it. Thanks man!