e85 tune?

well I'm not daily driving my car anymore so I was thinking about switching to e85 fuel. I know that I can gain power by doing so, which is always nice. my gas mileage right now is terrible and I know this won't help it much but I thought that if I have to get retuned I may as well step up and run e85. is there anything involved in this beyond a tune and larger injectors. I've heard that it eats away rubber fuel lines, true? keep in mind that i am running a vf39 with fmic. Thanks, Joe

 

You'd need to be able to adjust your fuel trims each time you fill up, as the blend of ethanol to gasoline is not consistant.


Tom?

 

and remember that e85 is not as accessible as other gas, in mn we don't have much problem, but take it elsewhere and you got nothing

 

interesting, I thought it was nation wide. up here in duluth there are only 2 stations but one is right near by so thats why I'm considering it

 

Yes, for the most part. The ethanol content is always changing. I've had so many people ask me for e85 tunes (and not just locally either) and I've turned every single one of them down.

Basically if you don't have the tools to continuously monitor and adjust your booze tune, I'd suggest to look into other alternatives.

 

wow, that really isn't worth it for me. I do have the means to tune but not the knowledge so I guess I won't do this anymore

 

Its pretty easy to adjust your injector scaling when they change fuel mixtures, you can figure it out.

 

Before you totally give up on it, try mixing some of the E-85 with you're regular premium. (in stock setups, you should be able to run 20-30% e-85 no problem)
In my stock 02' wrx, I like to run about 4 gallons of e-85 to a tank.
It is enough to make a big difference, (but dyno tells me so) and it is cheaper than 87.
Here is a link to a nasioc thread on E-85:
http://forums.nasioc.com/forums/showthread.php?t=803341&pp=25

I'm no expert, just sharing what I learned from reading, E-85 will need about 30% more fuel than if you were running straight gas, so if you're injectors won't allow for at least that much fuel, it would probably be best to stick with a mix.
According to a few on the thread above, to run E-85 on the wrx/sti, all you will need is bigger injectors, pump, and a tune.

Walloftvs, do you have any for instances of how much the ethanol content varies?
Wouldn't it be possible to tune conservatively for a "worst possible scenario" (all ethanol?) So if you got spot on e-85 or e-80, you would just be running a little rich?
I'm sure I'm missing something here (just beginning to learn this stuff) so please enlighten me!

 

Yeah, right around now is when the stations are carrying the summer blend -- and thus the fuel will have the highest ethanol content. You could then tune for that and then let the car run on the rich side as the ethanol content decreases.

I'd still suggest running a perm. mount wbo2 sensor, though.

 

Also, if there is a tuner that is willing to do an e-85 tune, speak up (pm me if you prefer).
It is my goal (once my 02' is payed off) to eventually end up with a stage 2 (with bigger injectors and pump) that can run e-85.
We are probably talking a year or more down the road at this point though.

Also, as for the variablility of the ethanol content, is the end product really that much more variable than the quality of straight petro? Probably remains to be seen...

I've lived in small towns (2-3 gas stations) all my life, and have noticed differences in gas from station to station.
For instance, in one town, (2 gas stations) one station would always be cheaper than the other by at least $0.02 My ford fiesta, and ford aspire both got better mileage on a repeat basis going with the more expensive fuel of the same octane rating.

 

Yeah, probably the best idea.

 

It's a well known fact that the refineries run at least 3-4 different blends during the year ranging from e85 all the way down to e70. http://www.e85mustangs.com/regions123.html

I made a point to go two weeks without adjusting any fuel trims between about 3 fillups. The first fill was dialed in at a proper 12.5:1 (gas equiv.) afr. After the 3rd fillup (from the same station), my afrs jumped to well into the 13.2ish:1 territory. :eek3:

Luckily the car wasn't knocking but it had a noticeable power decrease -- max torque is achieved on e85 right around the 12.5-7:1 region and anything leaner than that can actually lower power output.

The crappy thing about the '06 WRX is that it takes a really long time for the LTFT to migrate over to open loop WOT fueling -- long enough where I don't believe it is reasonable to just set it and forget it. Essentially by the time the ecu learns to compensate you are already on another tank of fuel since your gas mileage goes to hell with this stuff (lol).

 

Here's some information from the state about E85 including the locations of places that sell it. (over 300 in MN)

http://www.state.mn.us/portal/mn/jsp/content.do?subchannel=-536881511&sc2=-536888997&id=-536881350&agency=Commerce&sp2=y

 

I am also interested in running E85. when I get my 22T going it will drink the corn juice like none other. Perhaps for those who are truelly involved, mixing your own fuel may be the most consistant method. I know of people on RS25 making their own ethanol and doing their own blending.

 

Don't you have to get a license to have your own still?

 

Yesterday i but like 6-8 gallons of premium and added 2 gallons of e85 and got a CEL :-(

 

maybe, you need a license to do alot fo things. The laws maybe different in other states. none of the people making their own lived in MN. If you make your own why run any gas, just go straight ethanol.