AFR targets at loads higher than 2.50 ATR/ATP fix

[Lex]

The MAF sensor reading is all over the place in the log. That's the first thing I would look at addressing.

Did you change the fuel scalar for E25? If not, the ethanol itself will make the AFRs leaner.

[ledfootrob]

Yes fuel scalar is changed for that tune. Its a bad log to show as my boost dial was setup up for a lower boost tune but I was just using it too show that at 2.5 load AFR remained on target, but using pump fuel with a stock fuel scalar the AFR goes into the 9's using the same maf cal.

Originally Posted by Lex The MAF sensor reading is all over the place in the log. That's the first thing I would look at addressing. Did you change the fuel scalar for E25? If not, the ethanol itself will make the AFRs leaner.

[qkrthnu2]

Originally Posted by Lex Once it drops below 2.50 it goes back to the normal tables so you might see some oscillation if you're around the 2.50 mark. Also with the MS6 specifically the VVT VE table has a large effect on fueling as soon as you change the VVT advance table from stock.

@Lex Does this warning only apply at loads above 2.50?

Looking at the COBB OTS maps, they're making quite a few VVT Advance changes between Stage 0 v233 & Stage 2 v233, however they're not touching the VVT VE comp table. Is that just an omission on COBB's part?

The VVT VE table is hard to interpret, the values sort of correlate with the VVT Advance table as a large pattern, but individual cells are all over the place more like the VE table.

I thought I could make sense of the stock map @ the 2500rpm / 2.00 load.
30 VVT timing x VVT VE comp of 0.0310 = VE of 0.9333

But not everything lines up nice with my assumed math (I'm probably wrong/missing factors). e.g. 2500rpm / 1.00 load
VE of 0.9700 divided by VE Comp of 0.0280 = 34.6, so I would expect to see 35 in the VVT Advance, but it's still 30.

[Lex]

The VE table is most likely experimentally determined and not mathematically. In other words they put the engine on the dyno and after choosing the VVT advance desired and adjust final trims via the VE table. Even if it was a mathematical model we won't be able to use our current data for making calculated adjustments.

From what I've seen the most affected car is the MS6 and the effects are most visible under steady WOT.