Hello,

I have read a few people that put 1/2 e85 and some all e85. Can the stock ECU compensate correctly for the increase in octane if you use 100% e85? As I understand you will need larger injector - What about stock engine & stock ECU with maybe 410cc or 440cc injectors and 100% e85? Any other info or experiences will help!

 

i doubt it can compensate.. fueling so much different its not even close. But if you wanna try it and try to get it close the best thing you can do is, change the fuel system.. do a return setup and try to compensate by making changes in fuel pressure.. you might get it close but im almost 100% its not gonna be even close to perfect

 

thanks for the input- I do have a return system which I know will help. I really wanna try it. I think I prob will I have been know to be a pioneer lol

 

yeah im curious how it works with NA route... im gonna say do it, fuel return 550cc injectors.. I/H/E.. im sure you can make it work with piggyback and advance ignition

 

You wouldn't be able to advance ignition with a piggyback

 

i've had emanage for a short time, timing map does allow you input positive numbers.. im assuming you should be able to.. as what i've heard from users

 

can not advance timing with fi/c, it is possible with eManage though

 

All you need to run E85 in an NA tC is a set of 410cc injectors from the TRD supercharger kit and stock pump. If you already have a 255 pump with your return system you will just have to turn the fuel pressure down a little. The only down side is fuel consumption and hard starts in the winter.

-Jeremy

 

^^ you have done it?

 

Your vehicle was designed to run on 87 octane, why would you want more if your vehicle is stock? Unless you're going to boost it, I see no reason to do this.

 

REally its not N/A I just wanted to see how it works with the stock ECU and no tune. I run no tune at 7psi with 91oct and figured it would only make it that much safer with the e85 no tune. I know I know, no tune is not the best way. But it has worked flawlessly for me and the drivability, gas mileage, and throttle response is amazing

 

Yes I have been running E85 for a year and a half.

-Jeremy

 

how was your fuel trims? any cel?

 

watching...

 

Fuel trims were good. I pulled a little fuel out under wide open throttle with a camcon. With a stock fuel pump the fuel trims would be right on with the 410cc injectors. No cel.

-Jeremy

 

thats good to know.. we should see more running e85 na then haha.. so camcon only used right but only for WOT? other than that all stock ecu? do use a wideband gauge or you just do an obd logger when you were checking the tune..

 

does e85 in itself add power or do you HAVE to advance timing

 

I use our dyno.

You usually see about a 5% increase in power. It would be more beneficial with higher compression and an increase in timing. We will see soon!

 

E85 ads about 6-8% over pump gas, now don't think for a second that it will be safer to run it without compensating for it, cuz u'll run lean as heck and boom. I've seen sti guys blending up to 25-30% e85, but their ecu can compensate nicely up to +20 fuel trims. Not sure if ours do, some of them just put in bigger injectors, but it's all a gamble when it comes to the size. Try by going 30% bigger than stock and that should get you pretty close if you don't have a return system.

 

ive switched few times ethanol and gas and even changing by % on the fuel map isnt enough to get a perfect afrs as the it was.. imo e85 is just different in some ways, thats the reason why % change in inj pulse width is usually greater while on boost and while on cruise also tip in tune is slightly different.. stock ecu might be able to compensate+injector size change but i think fuel trims across the board will not be so smooth..