I have been looking at E85 conversion kits on-line. My impression is that they are drastically overpriced. The going price seems to be about $500 for a 8 cylinder model, for a device that should only cost about $50 to produce.
Here is my impression, you connect this device between the ECM and the fuel injectors, and the device stretches the injector pulse to allow more fuel.
Some of these kits claim to automatically adjust for E85 or gas. I don't see how this is possible, as they have no connection to anything besides the injectors, no connection to MAF, or knock sensor, or O2 sensor.
Anyhow, they claim to stretch the injector pulse about 30%.
I am considering making my own device, perhaps to sell.
Here are some questions:
1) Would you start the fuel injector pulse when the ECM starts the pulse, and make it longer, or would you sync with the ECM and make the pulse start earlier as well as end later. I don't know how the beginning of the injector pulse corresponds to the valve opening.
2) How would you determine what kind of fuel the car is running on.
Apparently there are EPA legality issues involved with such a device. There also seems to be some dispute about the effect that E85 would have on the fuel system of a car not designed for E85. We have been using E10 in Colorado for many years, I assume it has done a good job of dissolving sludge in everyones gas tank.
I have heard (no clue if it is really true though) that E85 is much more corrosive and you would have issues with the tank, seals, fuel lines, ect. as well as the injector issues.