Stupid Question

[Zapthepunctual]

What is required to run E85? I know ethanol can eat up the Buna-N o-rings, and the hoses, but apart from that I can't think of what else I would need. Has anyone else tried this?
I know there will be a performance hit but for around the town driving, it might be okay

 

[amaymi]

E85 requires a richer mixture for proper combustion. That's the biggest difference in flex fuel vehicles. When the computer senses that E85 is being used it switches to the maps for it. You will need someway to compensate for the richer mixture needed. From my experience with other cars usually its a little more complicated than just sticking on bigger injectors or upping the fuel pressure and people end up using stand alones or fuel management systems.

If done properly there will be no performance hit. In actuality because of E85's higher "octane" you could stand to gain performance with advanced timing and higher comp etc. You will experience a fuel economy decline however because of the richer mixture needed.

 

[O-Gauge Steamer]

Try this link

http://www.change2e85.com/servlet/StoreFront

They sell a kit with an additional injection controller. Turns the vehicle into a flex fuel.

 

[crimsondragon]

Depending on your model year, I think the fuel tank might need a coat on the inside to prevent the E85 from eating away at the metal. Not too sure about the later, plastic tanks. Also I think the fuel rail should be anodized. I can't remember for sure if the XJ fuel rail is aluminum or not.

 

[Zapthepunctual]

thanks, I was just curious, for my around town trips to save a little money

 

[bjoehandley]

I was talking to a guy a couple months ago who did that to his '92 XJ and all IIRC all he did was get a control unit to up the fuel flow. His truck had over 200k on it at the time and was his DD too. I also was talking to a friend at my gym about this a couple weeks back and he figured that on anything that still uses a distributer should be easy to bump the ignition timing on just by rotating the distributer a bit to advance it. He was also telling me that he built an engine for a guy's '89 Mustang using almost a completely factory fuel system and the guy has since put 40k on that car so he figured it would be a good time pull it apart and check things out. He found that the factory fuel system components were actually cleaner than they were 40k miles ago, the pump and injecters (which were the only mods) were perfectly fine, and the engine had less wear and tear that a performance engine with 40k should have on it! He was so impressed with the above findings that he's planning on swapping his own built, '89 Mustang Convertable over to E-85!

 

[O-Gauge Steamer]

WE are (eventually going to convert the XJ and my Wife's Bronco (full size aircraft carrier) to E85. My Son is considering it for his Subi as well. In the long run (could take a couple of years, depending on miles driven, to be honest) you will break even and then get ahead.

 

[XJEEPER]

E85 cost per mile

Based on my limited knowledge of the product, it requires more fuel that gasoline to produce equivelent power, so mileage will decrease.

E85: 15MPG x 2.57/gal
$0.171 per mile​

5.837 miles per $

Gas: 17MPG x 2.79/gal​

$0.164 per mile
6.093 miles per $



Why again would I want to convert to E85?

 

[DanMan2k06]

Because it's the *environmentally correct* thing to do...

Screw ethanol, convert to biodiesel and be done with it

 

[bjoehandley]

E85 cost per mile

Based on my limited knowledge of the product, it requires more fuel that gasoline to produce equivelent power, so mileage will decrease.

E85: 15MPG x 2.57/gal
$0.171 per mile​

5.837 miles per $

Gas: 17MPG x 2.79/gal​

$0.164 per mile
6.093 miles per $



Why again would I want to convert to E85?

Based on my understanding, if you're looking to convert an engine that's pretty much wore out and nearly in need of a rebuild, it's probably not worth bothering until you rebuild it. If it were a newer engine and you can get away with bumping the timing (like I mentioned earlier) and should be able to gain some of the lost mileage back if that's all you wanted to do. Another advantage is that since E-85 doesn't have as much carbon in it as E-10 or 100% gasoline, the engine oil, combustion chambers, and the entire fuel system will stay cleaner and should reduce the amount of maintenance needed when compared to a engine that only burns gasoline an that should reduce maintenance costs as well.

Now if you were looking to hot rod the recipient in some way, it would really be where the E-85 would be worth while. Since E-85 is usually over 100 octane like race gas, you can bump the compression ratio if you're going to stay naturally aspirated (Dad figures 13:1 with the iron head and maybe as much as 14:1 with an aluminum head on the 4.0l) and get all that power and mileage back, if not more than what you would lose otherwise. If you wanted to keep a stock or slightly lower compression ratio and put a turbo or supercharger, you can run more boost than you could with any normal pump gas and maybe even some race gases because of the high octane and cooling effects alcohol can have on the pressurized air/fuel mixture (kinda like water/alcohol/methanol injection on turbo diesels) too. If I were going to build an engine to be E-85 friendly motor for my XJ, I would probably build a turbocharged stroker using stock or slightly lower than stock compression so I can run multiple fuel/boost maps using boost and fuel controllers or stand alone engine management system which should allow me to run anything from the worst 87 octane pump gas I can find to E-85 or unleaded race gas just by screwing with the controllers once the proper fuel is in the tank. It would likely be the same with a factory turbo motor and all you would need to do with a supercharged motor beyond that is change the pulley to bump the amount of boost you get out of it.