Rough VE Table

I keep reading about how it is important to have a smooth VE table. Well, I am using a brand new Wideband and did OL SD VE tuning. I have areas that jump up 10 from one column to the next. I did logs and specifically held the car at the high points in the chart and then let it move up or down to the next point in the chart and according to my Wideband it is exactly right, these are adjacent cells in the chart (I was getting hundreds of hits and the results were constant). This is not in an idle cell, it is midrange from around 3000 to 5000 rpm and anywhere from 40 to 90 kpa. I left the peaks there and then tuned the MAF in OL and then reenabled everything. The LTFTs are 0 to -2 in the entire range even across the huge peaks and valleys. I am unsure what to do. If I smooth the VE table it ends up causing really lean and rich spots in adjacent cells. Not sure what to do. It definitely isn't smooth at all but according to all the sensors and logs it is correct. Any advice? Should I smooth it and then let the LTFT adjust or should I start adjusting the VE using STFTs? I can't see a way to smooth the VE without going from correct to incorrect values.

You should post the tune and log always.

So the wideband says its right, and the trims agree?

The VE is generally smooth, but if everything is fine then its shape doesn't mean anything. Huge peaks and valleys are a little odd, however.

Here is a log of me driving home last night. Very easy driving nothing special but I wanted to see if you guys could take a look at the log (I focused on the STFT). The LTFT and STFT are very close to where I want them, a little negative but pretty close to 0. There are some spots that are a little high but those areas aren't a concern, they may be bad data. The majority of the data is really close to 0. Could you take a look at the VE table, the LTFT and STFT numbers and confirm that if I were to adjust according to the trims that my peaks and valleys would be worse....I don't like how the car drives now that everything is back to normal, ie CL and DFCO. It felt better in OL but I really want to keep the MAF for automatic corrections. If you see anything I missed or that may be causing this very rough VE table please let me know. Im thinking if the VE was smooth it may feel a little better to drive? It just feels rough and not as smooth as it did in OL. Thanks again for your help!

Looks like you need to "copy with labels" the Primary VE and paste it into the Secondary again, since it's a little off. Tell us about your engine/drivetrain setup, so maybe we can understand why some of your numbers are so high.

How about your Maf curve? You could smooth that a little too, but that's just me.

I just swapped to an LS2 with an LS6 intake. It has a 226/230 about .600" lift on a 111 LSA cam. The transmission is bone stock M6 with a RAM Clutch. everything else is absolutely stock. Thanks for the reply

Did you turn off PE when you were tuning the VE?

How exactly are you suppose to set up your tune to allow a good VE tune? Is there a write up on how to properly do this?

Lumpo this link has good info for VE tuning, start reading at post #13. Hope this helps. http://www.hptuners.com/forum/showth...ning+idle+lean

I saw the same thing when I tuned my VE and I have about the same cam profile. If you smooth the VE any then your fuel trims go positive or negitive, depending on where it falls. I went back and got my VE as much as spot on and left it. I think what causes the peaks and valleys is from the cam profile. You don't want fuel trims running very far from center.

It's just my opinion but I think it's better to have proper fueling to the engine than a nice looking VE table. I know it might look like it's jumping around as it goes through the table but if the engine is calling for it then I don't see why to change it. I'm not an expert on tunning