ol maf tune or ve maf open loop and lambda question

[400ss]

Hi everyone. Im in the process of tuning an ls6 that is on a xj cherokee. Im on the maf tune. Runing a open loop maf. Tuning it on the street. On part throttle and idle and cruise. Where 14.68 is commanded. Is acceptable .99 lambda??? With engine temp it changues a litle but most of the time is .99- 1 lambda.. can i stay on maf only or is better to tune the ve too and run a ve maf open loop. This car is for offroad. Doesnt have 02s

[limited cv8r]

A benefit of tuning the VE would be in case of a maf failure for some reason, you would then know that your fueling is still safe.

[400ss]

You are correct, i think the lm1 stoich is 14.7 and thr stoich in my tune is 14.68. Should i changue the 14.7 to 14.68 using lm software

[joecar]

Can you tune using Lambda (from the LM-1)...?

( it is simpler, the MAF and/or VE correction factor is {GM.EQUIVRATIO} * {EXT.WO2LAM1} regardless of stoich AFR )
( of course, you set B3601 to the stoich AFR of the fuel you are running )

[joecar]

+1 I would do both MAF and VE.

[limited cv8r]

Depending on your OS you may also have something like "{B0120} RPM Threshold For Airflow Calculation"

[400ss]

Can you tune using Lambda (from the LM-1)...?

( it is simpler, the MAF and/or VE correction factor is {GM.EQUIVRATIO} * {EXT.WO2LAM1} regardless of stoich AFR )
( of course, you set B3601 to the stoich AFR of the fuel you are running )

That was exactly the answer i was looking for,,, I did tune it with lambda, using the lm1 with serial connection, but i was unsure if the value programed for stoich in the lm1 changues the lambda output... it looks like it doesnt then, i leave it like that..

the other question:: What is an acceptable BEN??

[joecar]

By using Lambda and/or EQR (which is 1/Lambda) you can simply ignore AFR...

( you simply set the stoich AFR in the tune file (e.g. table B3601 for LS1B) and then ignore commanded AFR and ignore wideband AFR ).

Acceptable BEN is 1.00 +/- 0.03

See the calc_pids.txt file in the post #1 of the Calc.VET thread (https://forum.efilive.com/showthread.php?15236-Calc-VET-correcting-MAF-and-calculating-VE-(in-single-log))

[400ss]

Thank you. Im already using that calc pid and already tuning with EQR and lambda and using commanded AFR pid and Wide Band AFR pid just to see it because im used to see AFR. Thank you again, i understand now