Tuning only for ethanol with no flex sensor

[Kboot6]

Want to know if it will be possible to tune with ethanol only and no flex sensor. Has anyone achieved this. Wouldnt you have to disable o2 sensing so the fts and ftl dont chase 14.7.

Thanks

[Matt]

Yes many people just tune for E85. Some disconnect the narrowband, but you can leave it enabled

Sensors measure the ratio of air vs exhaust gases which is measured as lambda, this is normally reported as a multiplier of air/fuel based on fuel type. Narrowband effectively are still targetting the same lambda (1) despite the parts of fuel and air required (which is based on fuel type)

E85 has a different AFR required for stoich than standard gasoline, but both still result in the same lamba

[Kboot6]

yes ok. easy i was thinking that the ecu would chase 14.7 afr not lambda, if it does chase lambda makes it exactly the same as you would tune for unleaded then?
correct?

[Matt]

Lambda at stoich is 1.0 which is a gasoline AFR of 14.7

Narrow band sensors always chase stoich (1.0 lambda or gasoline AFR 14.7:1)