Vitural VE changing in all the wrong places

[Naf]

Ok, i got my engine engine dynoed and they sent me the file, but in the car my idle is slightly lean, 15.5-17.2. I tried to just change the 400-1000 where the problem is, but when i look at my changes, it also makes changes all over the place. And i cannot reverse the other cells at all.

How may i just richen my selected areas without messig with the rest of the map???

[joecar]

Naf, can you post your file...?

[Naf]

Sorry it took me a while, but my log was a little too long to post as it was...

Everytime i try and fix the VE below 1000rpm in the areas that are lean it alters everywhere else.

Thanx for your help, and if you would share your knowledge on how you do it in selected cells only, i would be extremely appreciative

[GAMEOVER]

Thats what sucks about tuning the VVE, I couldn't get it to change where I wanted it to either....That's why I went MAF only....Easier & faster to tune with a wideband of course...

[joecar]

I'm not up on VVE, but someone here will know...

[ScarabEpic22]

Im tempted to tune my SS MAF only then dial the VVE in and see what driveability is.

[Naf]

If i increase the MAF values what happens to the AFR?

I cant remember, its been a while since i messed with one...

[wesam]

if you increase the MAF the the car will go lean

[Meister]

There is nothing wrong with tuning MAF only. You can pickup some throttle response and drive-ability by doing both VVE and MAF.

[joecar]

Hi wesam,

If you increase the MAF table, then then ECM will calculate an increased cylinder airmass, which in turn causes it to calculate an increased fuelmass, which causes wideband measured AFR to be richer (since the actual airmass is unchanged).