gen 4 vve tuning

I have a 2008 Chev with a new 4.8 engine and lumpy cam, and am having problems with the vve tuning. Have gotten the startup sorted out and it idles ok in closed loop but runs rough in open loop and the ltft #s are +15 below 1400 rpm, above that speed all seems good. I have tried to increase the vve table by just straight out increasing the vve table in that area(man.switch open-closed etc.) and by using stft+ltft graphing and applying that table to the vve table with appropriate maf disabled with no changes at all in the way it runs-fuel trims always go back to +15. I have lots of experience tuning aftermarket fi but my first go round with HP, and having troubles understanding many acronyms and exactly what many of the graphs/tables are for? Any nuby advice would be much appreciated-please be patient with me. At this point getting the ltft numbers in line will be a good start.

Post a log and tune. I would put it in full MAF mode for now, dial the MAF in first, then log VE air, Dynamic Air, and MAF air. You can then get the VE (VVE) closer while in full MAF mode. MAF is much easier and more forgiving to let you get close.

Do you have a wideband? You will need one to get WOT dialed in.

Will attempt to post a tune file shortly(still Learning). I have tried with maf on and off, by "dialing in the maf" do you mean maf calibration airflow vs frequency table? I do have a wideband available but not concerned with this yet-once I can get fueling below 1400 the rest will progess easier.

Here is a tune file. Do not have a log file(one step at a time)

Using a wideband is better than fuel trims.

I do not disagree at this point but my problem is I cannot get the fuel trims or fueling at all to respond to changes that I am making! I assume I am doing something wrong!

Make sure your logging MAP in your histogram as KPA and not something else, make sure you copy your vve table (after changes) and paste it in the manifold switch closed, open and or/whatever else it's called in the drop down to the left of the vve table. (sorry using my cell phone and don't exactly remember what all is labeled in the drop-down).

If it runs rough in open loop and better in closed loop with ltft that high, you need more fuel.

Yes, Airflow/General/MAF calibration/airflow vs frequency. Try calibrating the MAF first. Go to Airflow/Dynamic/Dynamic Airflow and set the following to something like:
High RPM Disable = 400
High RPM Re-enable = 300

Now it is running on MAF even at low rpm. Make a graph that matches your MAF hz, with the cells populated with your fueling error (LTFT, or EQ/AFR using wideband). Paste Special multiply by % (or 1/2%) to your MAF cal and try again. Plenty of info on how to do this in the stickies or youtube.

Thanks for the replies. I have created histograghs plotting the fueling error, pasted special and muliplied by %. Have also just tried adjusting the area of the vve table and maf calibration chart with mods that were anywhere from minor to drastic, and the vehicle will not respond. I have made changes to get it to start and idle better reguarding airflow and timing with good results. It just will not respond to fueling changes.

if you are using the wideband, put it in open loop.

I appreciate the responses, but, the process of tuning is not what I am having problems with. This vehicle does not respond to fueling changes after the "write" is done.

The reason that it's not responding to your VVE changes is because the MAF is still active. You'll have to change both the VVE and MAF table, or disable one of them.
Here you go. Try this one. I disabled the VVE and just added 10% to your MAF table at low freq's.Attachment 96078