VE correction factor

[pknowles]

Is VE correction factor the same as the VE predictive airflow that gets used in a blend SD and MAF tune? I'm running a two bar custom OS on a 2002 Tahoe flex fuel file. I've noticed that when I run SD only fueling is great, MAF only fueling is great, when I run a blended tune once I go over the my 2nd RPM zone boundary, dynamic airflow is under predicted (goes lean) and I think this is the VE predictive airflow going crazy because the VE predictive airflow coefficients (which we don't have access too) are not set-up for forced induction (turbo). Anyway, the VE correction factor min and max, are they limits on the VE predictive airflow calculation? Since I can't tune VE predictive airflow, I want to eliminated it, since my VE and MAF tables are dialed in. I'm thinking to either use the VE correction factor limits (if that works and has no other side effects) or raise the second RPM boundary above my High RPM disable limit to disable the VE predictive airflow calculation, which is messing up my fueling. VE predictive airflow doesn't seem to play a role until the second RPM boundary is crossed is that correct? Thanks.

[doorev800]

I am having exact same issue with a truck i am tuning. 2003 5.3 running a maggy blower and 2bar. I am surprised no one else chimed in on this. I have perfect fueling in maf only and sd only but dynamic goes lean between 2800 to 4000rpm. The ve airflow dips while maf stays steady and correct. So the ecu is calculating incorrect ve values in that rpm range. Going to try lowering dyn high rpm from 4000 to 2500 and see what happens.

[eXo3901]

VE correction is used to calculate dynamic airflow based on the MAF/VE differences during transitions from steady state to not steady state. It is likely not your area to fix this.

Log, at the same polling rate, dynamic airflow, MAF airflow, and VE airflow. Put them in a chart with the same upper and lower bounds and if they do not overlap each other (not perfectly but close) in steady state conditions you need to correct one of the MAF or VE tables.

[RADustin]

curious if anyone has learned more about the ve corrections? due to them being temperature based(and baro) I would expect they could really mess with you when tuning SD only at lower temps from operating temp. Has anyone ran into this before? Also seems like they could be messing with you while trying to dial in VE as they could be floating around making the correction factors skewed from the absolute VE numbers you're trying to apply them to.

I'm fixing to just set min and max to 0.999 and 1.001 and set table to all 1s and go from there. I'm getting a pig rich warm up idle on a SD P59 that once warm is perfect. Really racking my brain and this is all I can think it could be.