Originally Posted by
metroplex
I just did a quick WOT run. The EcoBoost loves this cooler denser air.
Here we see the Wideband error ratio showing the greatest delta percentage.
STFT doesn't look too bad. LTFT+STFT averaged is mainly biased with the LTFT data. The LTFT data looks to be positive in the 6-7% range which is skewing the results that way. On my SHO, the mapped points 0-3 are the ones that have the most useful data. The trend is about the same or worse for MP1-3 using the EQ Ratio Error data (we're talking -10% to -17%) at high RPMs.
I'm not so sure I need to adjust anything at this point. Even with 18 psi of boost and the extra air flow (52+ lb/min of air mass vs stock 38 lb/min), the actual wideband data shows slight lean during initial WOT, and then it follows the commanded lambda and dips down to 0.78 for some reason right near 6000 RPM (COT shouldn't be kicking in as the cat temps are still good, and commanded lambda is still 0.85). Once it upshifts, it will remain at the commanded 0.85 maybe dipping richer briefly.