WOT constantly lean

[wheezer]

I finally got my Wideband installed and have made decent progress. The only problem I'm having now is in SD tuning going WOT, I can't do better than ~3% lean. No matter what I do (multiply, multiply by half), it still stays around -3

Is this as good as I'm going to get it?

Also, I noticed the IFR goes from 30lb/r to 27.6lb/hr when in PE. Is this normal?

I'm commanding 14.3 and getting that and commanding 12.8 in PE and getting ~13.0 in 1st gear and ~12.8 in second gear, which also seems strange.


The biggest WOT run starts at 36:30

Edit** Log file is too big to upload. Download from here: www.allenowenphotography.com/z06/WTF.hpl

The car is stock btw.

[oakley6575]

Specs of the motor?

[wheezer]

Grandprix GXP. Its the LS4. 5.3l stock with only kn filter.

[MikeOD]

If you make a pull in 2nd gear it hits the target AFR, but in 1st it's lean?

Are you only using 1st and 2nd to tune?

[gn2beatu]

First gear sometimes will vary by .2 AFR. It has differant gearing, accelerates the motor faster, so ya, it can be differant. You will even see differant MAP in differant gears. EX: 94 or 99kpa

Your only commanding 1.117 PE, why not bump it to 1.13 and see if you get your 12.8 in the higher gears.

[wheezer]

If you make a pull in 2nd gear it hits the target AFR, but in 1st it's lean?

Are you only using 1st and 2nd to tune?

I only noticed this in the WOT runs.
Throughout the tune, I've been using tap shift to hold third to get a lot of the cells populated, but there's no way without a dyno (or at the track) to get WOT 3rd gear in the high RPM range. In hindsight, I should have been logging what gear I was in.

First gear sometimes will vary by .2 AFR. It has differant gearing, accelerates the motor faster, so ya, it can be differant. You will even see differant MAP in differant gears. EX: 94 or 99kpa

Your only commanding 1.117 PE, why not bump it to 1.13 and see if you get your 12.8 in the higher gears.

I'm getting 12.8 in the higher gears, just not first, so your explanation makes sense. Since first gear goes by so fast I guess it doesn't have time to settle into the commanded AFR.

The other question I had was the injector flow rate goes down to 27.6 lb/hour at WOT. Is this normal? Not knowing much about it, my common sense thinks it would increase.