E-85 and ECMLink question

[91talon27]

First off I have been searching information about E-85 for about 2 weeks. I have learned a lot about what I will need when I deciede to do the conversion. What I am curious about is this. Stoich on gasoline is around 14.7:1 and on E-85 it is near 9:1. Does that mean that under cruising conditions my wideband should read 9:1 or am I confused about that information? The other question is I am buying ECMLink V3 in the next few weeks. Does it support mulitple fuel maps? I want to be able to switch to a pump gas map if I'm somewhere that E-85 isn't available.

 

[My1GLaser]

Your WB will read the same as running pump gas. Mine does anyway. I am running a 50/50 blend of E-85 & pump.

As far as multiple fuel maps...yes you can. You basically just save a tune and label it pump gas & do the same for E-85. I had a street tune and race tune saved on my desktop and could load either one in a few seconds.

You will end up with some E-85 or pump in the tank and won't get a 100% mixture if you have to switch over. It shouldn't make too much difference to have 2 gal of one or the other mixed in a full tank. About 2-4% global chg depending on inj size.

 

[91talon27]

Ok so I think I'm confusing myself on this. Even though stoich on E-85 is 9:1 my wideband will read 14.7:1 under cruising and idle. Is this the same for wideopen throttle while under boost? I won't be using the pump gas tune unless I absolutely have to as if I'm somewhere and low on gas with no where to get E-85. I would just like to have the tune just in case that ever happens.

 

[2gGSXEclipse]

Ok so I think I'm confusing myself on this. Even though stoich on E-85 is 9:1 my wideband will read 14.7:1 under cruising and idle. Is this the same for wideopen throttle while under boost?

Dont know what stoich is on e-85 but your WOT and cruise AFR's will be different. Your WOT should be ricer. Example I run stoich while cruising but i am running 11.0 -11.5. I am using gas though not E-85

 

[1twistdtalon]

id say for sure you will need bigger injectors 1000cc or so if you plan on running straight e-85 and you will want to make sure you have your fuel pump re wired and at least a wally 255 or equal to. better to have to much fuel then not enough esp since you will be running a d link.

 

[matthewdesigns]

Ok so I think I'm confusing myself on this. Even though stoich on E-85 is 9:1 my wideband will read 14.7:1 under cruising and idle.

Correct.

Is this the same for wideopen throttle while under boost?

Your wbo2 will read as it would if you were at WOT on pump gas, which is to say richer (hopefully), just as your factory ECU map operates with pump gas. Typically, with a tuning device, people shoot for WOT afr's on pump gas around 10.5-11.0:1, and on e85 around 11.5-12.0:1 since it has greater knock resistance than gasoline. I generally try to target 11.7-8:1 with my car since that's where it likes to be.

 

[Croaker]

i'm set up with 2 maps on my ECM-link and an underdash switch to go between gas or E-85. RRE did my last tuning run and it ended up at 12.3:1 on e-85. I am also running 1000cc injectors as is recommended above, trust me you'll need them. Yoiu'll also want a Walbro 255 fuel pump w/ the hotwiring to support the injectors too.

Milage may not be the greatest but it is hella fun. ~60% awhp and ~50% torque with tuning, cams, MBC(20lbs), pump and injectors on a t-25 is .

 

[jrohner]

id say for sure you will need bigger injectors 1000cc or so if you plan on running straight e-85 and you will want to make sure you have your fuel pump re wired and at least a wally 255 or equal to. better to have to much fuel then not enough esp since you will be running a d link.

No, 1000cc injectors are not necessary with a 16G on E85. The 780's will be about perfect unless you upgrade your turbo. Yes to the wally 255 though.

 

[91talon27]

Correct.


Your wbo2 will read as it would if you were at WOT on pump gas, which is to say richer (hopefully), just as your factory ECU map operates with pump gas. Typically, with a tuning device, people shoot for WOT afr's on pump gas around 10.5-11.0:1, and on e85 around 11.5-12.0:1 since it has greater knock resistance than gasoline. I generally try to target 11.7-8:1 with my car since that's where it likes to be.

Thank you...That is exactly what information I was looking for. I know that the AFR with gas at WOT is near 11:1 I was unsure if with E-85 they should be richer or leaner. I will be running Blue Max 1850cc injectors and dual Walbro's as I am going to be running a Precision T3/T4 HP6057. Just a FYI this is going to be going a fully gutted, caged FWD 5-speed.

 

[My1GLaser]

Just as an FYI, there are a couple locals running 12.5-13:1 on straight E-85. They are running 3 different 9 sec auto 1gs. (1 might be his 10 sec street car IIRC)

I run about 12.5:1 on 50/50 E-85 & pump. I am also getting away with 24* timing running 28ish psi on an 18g. It spikes to about 34, but holds 26-28 most of the time. Thus is on 950s at about 70% IDC & 42-44 lb/min airflow.

 

[91talon27]

So basically I can run the run the car slightly leaner due to the E-85 having less detenation.

 

[jeffo]

Yes, leaner AS READ ON A WIDEBAND CALIBRATED FOR GAS. In reality you are actually MUCH richer than the 11.0-11.5:1 you would be on 93 octane, but the WBO2 will read ~12.0:1.

 

[bry2gdsm]

Man I Wish The Would Bring E-85 Where I Live.... All The Fun & Power I Am Missing....

 

[91talon27]

Yes, leaner AS READ ON A WIDEBAND CALIBRATED FOR GAS. In reality you are actually MUCH richer than the 11.0-11.5:1 you would be on 93 octane, but the WBO2 will read ~12.0:1.

Thanks for the clarification. I think I have all the information I need now. Thanks for all the help.

 

[flinguist]

Read this. http://www.dsmtuners.com/forums/articles-tuning-ecu/253452-e85-injector-max-lb-min-calculations.html