That's not correct for a NA engine. A regular LSU 4.2 sensor will read down to 4.5 a/f ratio, which is well below the normal 5.5 - 5.2 A/f ratio that is normally seen. Now On a supercharged engine "normal" a/f is 4.2-4.4 a/f.

In addiction, the Daytona sensor wego 5 unit goes down to 3.2 a/f using the lsu 4.2 (Bosch) sensor. ( I have not use this controller)

Also any O2 sensor can be used for just about any hydrocarbon fuels. I have used mine for gas, e85, methanol and diesel. They all output 0-5 volts, it's the Scale factors that are different.

Joe