Stoich for methanol is 6.4:1, for gas it is 14.7:1. So if you are fueling with 30% methanol 70% gasoline, stoich is 12.2:1?
Soooo if your wideband shows 12.5:1, without much thought you would say you are rich relative to stoich (for gasoline of course), but in fact you are lean for the new...