speedofsalt32

My upper intake gasket is leaking, believe i was watching truck-u er gears with a episode how ethanol eats rubber, wanna get new injector donuts er whatever and intake gaskets and whatever else they got to run e85 NYS runs 10 percent ethanol by law

ajm8127

iTrader: (8)

I know E85 has a different ideal AFR than gasoline so to do this you would need to alter the engine management system. I suppose if you were to offset the O2 sensor voltage by a fixed amount, it may be possible to trick the stock ECU into creating the correct E85 AFR, even though the actual AFR would be different than what the ECU thinks it is. Running O2 simulators on your primary sensors and using a piggyback might be another method.

dgoodhue

iTrader: (1)

Agreed and it also requires about 30% more fuel.

Trust me that isn't going to work well.

ajm8127

iTrader: (8)

Considering the non-linear response of a narrow band O2 sensor, you would not be able to add a fixed amount of voltage to the output, but offsetting it by using some non-linear function should work as long as you get the cross over point at E85's ideal AFR. That way the ECU would see a too lean or too rich condition and adjust accordingly. You could then add or subtract fuel with a piggyback across the entire rpm range to make up for any difference that the ECU could not compensate for. As you say the E85 stoich AFR is much, much richer than gasoline, so you may have to even use bigger injectors with a higher fuel pressure and tune like that to 9.765 AFR

In open loop it gets easier, because you don't have to worry about the O2s and the stock ECU making AFR adjustments. If I did such a conversion, that's the path I would follow. Get the ECU in open loop the whole time and then just set a map with a piggyback/upsize injectors or add fuel pressure to give me the right AFR using a wide band sensor.

These are not detailed instructions, just rough courses. And this is not a simple project by any means.

SteveB123

iTrader: (2)

You don't need to go nuts changing out rubber seals for 10% ethanol, if that's what you're attempting to say.

Ethanol is used in many, many juristictions, without line ups of broken cars on the side of the road.

asand1

iTrader: (1)

I do believe our cars were built with E10 (10% Ethanol) in mind