VE reported air intake versus MAF reported air intake ??

[kestell123]

I have a 1991 camaro that I swapped a 2011 lc9 5.3 and 6l80 into. I had it tuned at a local dyno using HP tuners. It is a long story why but the but the car went to the tuners with a stock 2011 silverado tune in it. I did not like the tune they did so I ordered my own HP TUNERS suite and down loaded a stock 2011 silverado tune from the repository to compare with what they had done to the tune. What I found was that although they had changed the MAF map the VE map was unchanged from the stock 2011 silverado tune. When I asked them about this they said it did not need to change be cause the longblock was all stock so the VE would be unchanged.I thought because the intake has been changed from the truck intake to an LS2 intake,the MAF location changed. and the air filter system changed to a third gen TPI f-body that that would change the VE. When I logged it I was getting very different reported air flow numbers from the VE compared to the MAF.The MAF readings are much higher. Did they take a shortcut to save work, I was charged for a "FULL LS TUNE" Should the VE have been tuned? I am an old guy with alot of wrench time but this is new to me.Thanks In advance for any help you can give me .

[chevyalltheway]

Late response but if you haven't already figured it out. If you change anything around the intake/MAF from 100% stock then the MAF should be retuned, keep in mind the computer can compensate 25% without help from a tuner. VE is Volumetric Efficiency, change the intake and you will change the efficiency of the motor. Keep in mind the computer will still compensate 25%. The VE is a good guess from the factory but was not meant to run on it alone, if you remove the MAF the car will not run well unless it was tuned for it. Also keep in mind the exhaust will change your VE but not your MAF. There is much more to add to this info that would help you but you should probably just look around for a little bit and ask questions about answers you do not understand.

Ask a tuner to tune your VE and the cost goes up, the MAF is quickly tuned and most of the time that is good enough. When you run WOT the MAF is used for fueling. The VE is used primarily in throttle transient but the computer never relies 100% on VE.

[kestell123]

Thanks for responding, A question I still have is should the MAF and VE reported air flow be close to the same? My log is showing a much lower air flow reported by VE than by MAF and I some times get a PO101 code set.

[CatnipG5Bandit]

The reason they didn't tune the VE is probably because it is a PITA and so complicated they chose not to. Instead of a VE table they use polynomial equations to determine VE. Usually they will set the tune to MAF only and go from there. HPT is working on the Virtual VE table being editable but until then it gets complicated and you'd need to use bluecat's EQ>VE tool to figure a VE table.

Also yes, if your MAF is tuned and your VE isn't there will be a difference in airflow reported.