E-85 as an EFI Fuel

[GOvert]

Someone may have asked this question before so if they did here it is again.
An E-85 plant is being constructed within 45 minutes of me so real soon E-85 as a fuel will be available at a few stations near me. I hear some of the newer vehicles can burn E-85 and that may be what they call flex fuel vehicles.

My question is can a '93 8 plug 2300 be made to run on E-85 ? I would imagine some of the fuel delivery lines would have to be upgraded, and I'm sure something would have to be done to the computer if not changed entirely from a different newer vehicle. Does anyone have experience with this or refer me to a website that tells all about it ? Thanks in advance !

 

[Stinger]

Everything in the fuel system would be fine. You'll just need to be able to command the ECU to feed the engine roughly 30% more fuel to compensate for the lower stoichiometric ratio required for ethanol. The "cheap" way to do this is to throw in ~30% larger injectors. It would be far from perfect though...

 

[bhuff30]

It really isn't so easy... The actual ratio of ethanol in E85 can vary between about 70 and 90%. This throws off air fuel ratios. During the winter months, it has more gasoline to make the engine easier to start. So you'd have to retune a couple times a year. The OEMs making flex fuel vehicles have a sensor in the tank to determine the amount of ethanol and adjust the fueling accordingly, but it is even more critical in such an application because the owners may fill up with a half tank of E85 and a half tank of gas. I beleive there is support within megasquirt for making that work, but the sensors are prohbitively expensive (like $400+).

Having said all that, I ran the tank dry and drumped in some E85. To compensate, I installed larger injectors and used an adjustable fuel pressure regluator to get the AF where I wanted it. It's my toy, so I'm not worried about re-tuning and I doubt I'll drive it in the winter months anyway.

 

[65ShelbyClone]

I hadn't heard of E85 having up to 90% ethanol. The Department of Energy E85 factsheet says it only varies between 70 and 85%. I had also seen prices quoted for the GM flex fuel sensors in the $150 range. There is no real easy way to implement it with an EEC-IV anyway, so I guess it doesn't matter. As an FYI, it measures the dielectric constant of the the fuel. Gasoline is not conductive while ethanol is slightly.

MegaSquirt-II can use input from one, but not MS-I. Without a way to tune the computer and accurately deliver more fuel, the switch to E85 is not really simple nor easy.

 

[GOvert]

Electronic device

I found this little device that claims to widen the pulse width of the injectors.
http://e85vehicles.com/converting-e85.htm
The guy in the article did this to his Explorer and is happy with the results. It might be worth a try !