E-85 Conversion Kit

Showtyme

Original poster
Member
Nov 26, 2012
150
I've seen kits online for retrofitting your vehicle to make it flex fuel. It looks like most of them are just a computer that will adjust your fuel trims. It seems to me that there would be more you would have to do to your vehicle in order to safely run E-85 long term. Has anybody had any experience with these kits? Side note my work van is FFV and I run E-85 in it most of the time. Fuel mileage isn't as good but it runs so much better and with a noticeable power increase. Granted it has the 6.0 so there is already power to build on. I know the 4.2 wouldn't have as big of an increase but I still like the idea of running E-85. Any input is appreciated.
 

jimmyjam

Member
Nov 18, 2011
1,634
you'd need bigger injectors probably, possibly a bigger fuel pump. you're basically burning 40% more fuel so you need to move more fuel. you should be able to use the stock ecm and tune it to run e85 100% of the time, but idk. getting it to be "flex"-able should require a smarter ecm

just curious, how much does e85 cost in the midwest? its pretty scarce down here, and is only marginally cheaper, not cost effective. but if i was running boost i'd certainly consider it
 

navigator

Member
Dec 3, 2011
504
I saw it at a station about an hr away from me. At the time I had a mini-van that could run E85 but it was only like $.05 cheaper than the E10. I figured my mileage would suffer enough that it would more than offset the savings so I didn't even try it.
 

C-ya

Member
Aug 24, 2012
1,098
Here in southwest MI / northwest IN (Michiana), E85 can be as much as $.50/gal cheaper. Normally in the $.30/gal cheaper range.

As a side note, we just jumped $.26/gal yesterday for 87 - from $3.499 to $3.759. Wonder what is up that I don't know about? (Wouldn't take much!) I was able to fill the TB up on the way back to work during lunch as one station had jumped and the next one hadn't.
 

Shdwdrgn

Member
Dec 4, 2011
568
Wow that's crazy prices! What are you guys doing around there? My local prices for 85 octane has been holding around $2.65 for most of the month. Damn I miss $1 gas.
 

Showtyme

Original poster
Member
Nov 26, 2012
150
E-85 normally runs between $2.99 and $3.20 depending on regular gas prices. The highr gas goes the bigger the savings. The kits are a inline ecm basically that reads your o2 and adjusts fuel depending on how much alcohol is mixed with the gas. Descriptions are vague but make no mention of injectors or fuel pumps. They advertise as plug and play. Also e-85 burns cleaner and the motors like the higher octane. No rough idles or hesitation.
 

stormsurge

Member
Jan 29, 2012
386
You can run somewhere around 54% but your milage drops a few gallons per. mile. Its been a wile sence i read up on it. If i remember right it was 60lb injectors and a high flow fuel pump to run 100% E85 and a tune. I mix 1 to 4 once in a wile and get great power from it. Just in the ss though. I might switch some day.
 

CaptainXL

Member
Dec 4, 2011
2,445
I have read that E85 is roughly 110 octane so all that is needed is a tune for that type of octane. If you think about the injectors... why would you have to replace them? Don't flex fuel vehicles use the same injectors just different pulse widths? Also you need to think about getting a fuel sensor in case you decide to switch back and forth.
 

jimmyjam

Member
Nov 18, 2011
1,634
CaptainXL said:
I have read that E85 is roughly 110 octane so all that is needed is a tune for that type of octane. If you think about the injectors... why would you have to replace them? Don't flex fuel vehicles use the same injectors just different pulse widths? Also you need to think about getting a fuel sensor in case you decide to switch back and forth.
depends on were your injectors are at capacity wise. the 29# injectors in my ss were pretty close to maxed out after a head swap, no way they could flow enough to run e85

E85 Injector Sizing
 

CaptainXL

Member
Dec 4, 2011
2,445
jimmyjam said:
depends on were your injectors are at capacity wise. the 29# injectors in my ss were pretty close to maxed out after a head swap, no way they could flow enough to run e85

E85 Injector Sizing

Just curious. You said you have 29 lb injectors which if my calculations are right are the same as my I6. How do you know you/we have 29lb injectors? What are the published specs?
 

jimmyjam

Member
Nov 18, 2011
1,634
CaptainXL said:
Just curious. You said you have 29 lb injectors which if my calculations are right are the same as my I6. How do you know you/we have 29lb injectors? What are the published specs?
They are (were rather) pn 12580681. The only data i have is the stock HPTuners file that shows 29.42# @ 0kPA manifold pressure

an 06 I6 file reads 28.74#
 

CaptainXL

Member
Dec 4, 2011
2,445
Sounds right. I have been looking forever on Alldatadiy and at times it is frustrating that you can't find specs like this. Maybe its in there somewhere but I cant find it.
 

stormsurge

Member
Jan 29, 2012
386
CaptainXL said:
I have read that E85 is roughly 110 octane so all that is needed is a tune for that type of octane. If you think about the injectors... why would you have to replace them? Don't flex fuel vehicles use the same injectors just different pulse widths? Also you need to think about getting a fuel sensor in case you decide to switch back and forth.

You burn more fuel Using E85. Our injectors are to small. Flex fuel injectors are bigger. You might be able to run but not as good as you would with bigger ones. Again, its been a wile sence i checked on this.
 

Forum Statistics

Threads
23,404
Posts
638,888
Members
18,618
Latest member
4Q2 Motorsports

Members Online