E85 tune help

[ovenroastedlnf]

So i got a canned tune from zzp when i ordered all my parts for my lsj. They have it commanding 11.4. My wuestion is should my wideband be reading 11.4 as my "stoich" value or should it still be reading 14.7? I never changed the wideband for the fuel, hell i dont know if you even can. But cruising aroumd it stays around 11.4 and wot its commanding 9.12.

When i try to add fuel to get my to my target 9.12, it starts to break up and sound like a two step when I get on it. I am guessing I am running way too rich?

Any inputs would be appreciated. Thanks

[CatnipG5Bandit]

Widebands operate off lambda, so you'd want a wideband set up for gasoline to read 14.7 when stoich no matter what fuel or stoich value is used. Then whatever PE you want you'd calculate off 14.7 stoich. For example stoich on my ethanol blend tune is somewhere near 12ish, but I want to see 14.7 on my wideband during cruise. I'm NA so I'd still want to see 12.8 when in PE.

[ovenroastedlnf]

So in my logger, i have the wideband reading through the ac pressure sensor. And since the stoich value is 11.4, thats what it is trying to keep my fueling around and is my commanded fuel. So should I divide that commanded pid by .775 so it tries to keep everything around 14.7? Or should i chane the stoich value back to 14.7 in the tune and just adjust the fueling from there?

[CatnipG5Bandit]

Pretty much. You want the wideband to read 14.7 but you want the logger to read whatever your real stoich is because if the computer sees 14.7 when it is commanding 11.4 it would skew your tuning richer than it needs. In my gasoline pid I used (voltage * 2) + 9.87, but with the ethanol I used something like (voltage * 2) + 7.21 because my stoich was 2.66 lower than gasoline. It's better soon it that way instead of dividing or multiplying by whatever amount.

Ideally though one should work off lambda instead of afr at a certain point.

[ovenroastedlnf]

I prefer working with lambda, but i dont think the lsj has that option like the lnf. Or does it and I'm just missing it?

Either way, im going to change the commanded stoich back to 14.7 and set the logger to read it as the 11.4 and dial it in that way. Hopefully that gets rid of the annoying breaking up its doing

[CatnipG5Bandit]

Well you just change your equation in the scanner to have it read lambda. I'm sure there's a tutorial here somewhere. There should also be a mechanism on the back of the wideband to set it to lambda theoretically. Also leave your commanded stoich at 11.4. The only thing that should be 14.7 is the wideband

[ovenroastedlnf]

One more thing I noticed and forgot to mention, the fuel trims dont work at all unless i tell the car to run in closed loop through the scanner. Why is it doing this?