Review tune C5 Z06 P01

[edcmat-l1]

408TT.jpg

In this first screen shot if look at the line graphs, 4th down, your commanded AFR and actual. I didn't plot ARF error but you can see in the line graph how far apart they are.

In that screen shot the histogram, or chart, is your fuel trims plotted against the VE table.

408TT_2.jpg

This screen shot is the trims applied to your VE.

Couple things going on here. First, your injector data isn't right. If it were you'd have better control of the low-speed behavior. Your transient min fuel mg. needs to be lowered for one. There may be more that needs done I did not go digging through all the data I'm just going by what they're doing and how they're shaping the VE.

Second thing is, you need to be commanding more fuel in PE. You're commanding too lean a mixture until too late in the RPMs or boost level.

[C5Z06TwinTurb]

408TT.jpg

In this first screen shot if look at the line graphs, 4th down, your commanded AFR and actual. I didn't plot ARF error but you can see in the line graph how far apart they are.

In that screen shot the histogram, or chart, is your fuel trims plotted against the VE table.

408TT_2.jpg

This screen shot is the trims applied to your VE.

Couple things going on here. First, your injector data isn't right. If it were you'd have better control of the low-speed behavior. Your transient min fuel mg. needs to be lowered for one. There may be more that needs done I did not go digging through all the data I'm just going by what they're doing and how they're shaping the VE.

Second thing is, you need to be commanding more fuel in PE. You're commanding too lean a mixture until too late in the RPMs or boost level.

I will add these corrections percentages by half to the VE table, smooth it out, modify the transient min fuel mg to 0.012, modified PE for rpm and boost just to be safe, and lowered my min injector pulse width and default injector pulse to0.274 in the 0-1200 rpm range.

This is what is confusing to me..... I am following the GM characterization spreadsheet they provide on their website but everyone has a different opinion as to what the values should be for almost every category. If the document was just a suggestion and really its up to the car and tune I would be fine with that but I was under the impression these are hard values and ID had done extensive testing to provide them.

Ill log a run today and let you guys know the results.

[Alvin]

The transient section he is tell you to reduce (i zero them out) aren't about injector data. Its a If you need a transient and need more fuel you can fire the injector but it must be at least this amount. That "at least this amount" is far too much with larger injectors.

[C5Z06TwinTurb]

The transient section he is tell you to reduce (i zero them out) aren't about injector data. Its a If you need a transient and need more fuel you can fire the injector but it must be at least this amount. That "at least this amount" is far too much with larger injectors.

Thanks Alvin, yes I understand it as the smallest squirt of fuel your ECM is willing to bother with when you quickly jab or release pedal. So Im guessing with big injectors even very small corrections result in noticeable AFR changes. So Im confused..... why would I zero that value out? Wouldnt that make things worst? The original value was 0.032 would I increase the value or decrease and test?