0411 swap quirk/Calc VE question

[bmd2_colo]

Hey guys-

Swapped a 0411 into my 98 Tahoe, made some tune changes and loaded up the Express van tune, good to go.
Question is-

The Van tune is a 4x2 tune. The Tahoe is a 4x4 truck.
Just threw it into 4LO to see if it will throw a code-

5 mph in 4HI gave me ~1000 rpm, good to go.
5 mph in 4LO gave me ~1800 rpm, good to go.
No check engine lights...

Just curious because the differing output RPM should have confused the 0411... or maybe not?
Pin 16 on the red connector is the 4LO ground in from the switch on the transfer case, I'm assuming that this is how the 0411 knows to adjust the VSS. Just weird that the tune file makes no reference to this ratio change in the speedo adjust section.

Anyway, I'm thrilled that it works but I guess it is an anomaly. Not a 4L80E so I guess it can't compare the ISS to the output rpm/VSS.

Just a weird thing I noticed.

Oh, and I'm trying to just do a basic Calc VE (not the AUTO VE) using the NB O2s (no WB) in the truck... anything I need to add to the calc_pids file over and above the normal CalcVE calc_pid.txt additions? I've built the tables in accordance with the CalcVE tutorial, any changes for that? The CalcVE tutorial only mentions the WBO2 in two places... the first and third pages and then there is no mention of referencing the WB PID ever again.

Since the tables are built to calculate off of LTFT and the MAF Hz, I'm assuming that I'm set up properly to do a NB O2 Closed-Loop Calc VE session.
Also...
What about running a CalcVE but with the fuel adjustments disabled in the computer?
I still want the computer to calculate what the fuel trims should be, I just don't want the computer to APPLY them. Basically an Open Loop tune but still using the O2s data to calculate what the trims should be, just not actually applying them. Is that even worth it?? Better to just let closed loop do it?


Thanks for any help!!!

Mike

[joecar]

Make sure to use post #1 in this thread:Calc-VET-correcting-MAF-and-calculating-VE-(in-single-log)


If you disable trims (CL/STFT/STFT and SOL) then you should edit CALC.SELBEN to always select CALC.WO2BEN

[ CALC.SELEBN is used to correct MAF table and to calculate VE from this corrected MAF...
if you disable all fuel trimming, then CALC.SELBEN can simply select CALC.WO2BEN as the correction factor ]


If the PCM computes fuel trims it will also apply them...

If you go with CL, then the use CALC.SELBEN as defined in post #1 of the Calc.VET thread

[ CALC.SELBEN chooses CALC.LTFTBEN when in CL, and CALC.WO2BEN when not in CL ]

[bmd2_colo]

roger that, thanks joecar.
running with CALC_VET as per the pdf tutorial.

Thanks again