What does stoich mean?

[Greg Hermann]

>>We are using here in Brazil 22% of anydre alcohol in our normaly produced
>>cars, and there is no report about Lambda reading errors in the fuel systems
>>that we use ( Bosch,Marelli and GM).
>>The governement are planning to use next month 24-26% to decrease the fuel
>>importation ( petrol has increased the price too much).
>>Another point is that we are using cars with 100% alcohol a lot of years
>
>And what AFR does the gm ecms marketed there use for the Stoich value?.

The O2 sensor will switch at stoich with ethanol OR methanol, with no ill
effects, just like it does for gasoline. Stoich ratio for straight,
anhydrous ethanol is  9.0 : 1 , for straight, anhydrous methanol is 6.4 :
1. (!4.7 : 1 is stoich for a normal blend of gasoline, but varies somewhat
with the blend.) A sensor switches at whatever the real stoich value is,
not necessarily 14.7 : 1, regardless of the fuel blend.

Regards, Greg
>Bruce