An ethanol converter modifies the ratio of the fuel-air mixture in a way that the vehicle could work even when it uses E85 100%. After the installation the car can be used by pure bioethanol, pure petrol or any mixture of these fuels.
Why do we need converting? The specific energy of the bioethanol is lower than that of the petrol. For the same efficiency of the car’s engine when using 100% bioethanol we need to add more fuel. The converter which is connected between the car’s ECU and the injectors automaticaly set the fuel-air mixture in a way that the car can works perfectly even with 100% bioethanol, 100% petrol and any mixtures of these.