If you know the a/f ratio for stoich for the fuel you are using, you can program your wideband lambda value to reflect that ratio. For that matter, if you consistently use the same fuel, and you find that the engine likes a 13.1 ratio under power, you could set your wideband lambda so that 13.1 : 1 ratio is a perfect “1” lambda. It wont really be “lambda”, but it gives an easy to zero in on target.