How to run E85 on stock 86 BRZ FRS with OFT tune

[Sypher]

first time running E85. pumped about 11.5 gallons. I think everything looks ok as long as the ecu has a little more time to learn.

this is the log i ran today for about 20min. My real intrerest is trying to figure out what E85 tune to run. I have the FT86SF catted UEL. I've decided to try out the UEL tune but what do you guys think?

http://datazap.me/u/sypher/3-10-15-o...og=0&data=1-12

[steve99]

Originally Posted by Sypher

first time running E85. pumped about 11.5 gallons. I think everything looks ok as long as the ecu has a little more time to learn.

this is the log i ran today for about 20min. My real intrerest is trying to figure out what E85 tune to run. I have the FT86SF catted UEL. I've decided to try out the UEL tune but what do you guys think?

http://datazap.me/u/sypher/3-10-15-o...og=0&data=1-12

Looks pretty good to me

no knock fbkc or flkc
iam is 1
fuel trims 5% or less
looks like it might be a bit rich in places but probably due residual petrol in tank and fuel trims settling if it has not had much run rime.

shiv runs the stage 2 el e85 tune on stock catted header so the uel e85 tune on your catted header look fine.

[Trettiosjuan]

What is the difference between the UEL and EL stage 2 files? I also run the FT86SF catted headers, and runner length is only a little bit more unequal than the OE header...

[steve99]

Originally Posted by Trettiosjuan

What is the difference between the UEL and EL stage 2 files? I also run the FT86SF catted headers, and runner length is only a little bit more unequal than the OE header...

load both tunes into romraider and do a compare .

from memory its just the intake and exhaust cam timing

[Sypher]

Originally Posted by Trettiosjuan

What is the difference between the UEL and EL stage 2 files? I also run the FT86SF catted headers, and runner length is only a little bit more unequal than the OE header...

Originally Posted by steve99

load both tunes into romraider and do a compare .

from memory its just the intake and exhaust cam timing

when i compared them in romraider there is a good chunk of cam timing that is different.

Thanks again @steve99 for looking at that for me

[OkieSnuffBox]

Finally loaded up the E85 tune now that it's finally warming up here.


Pretty incredible difference! It was really cool to watch the fuel trims in real time as the computer was learning, insane stuff!


Now to add a UEL/overpipe/front pipe.

[Silver Ignition]

Originally Posted by steve99

negitive fuel trims result from adding petrol as it makes engine run rich when on E85 and ECU compensates by reducing fuel trim values.

as long as it not way over 10% it should be ok.

do a couple of light say 20% steady throttle runs in 2nd or 3rd from 2500 to 5000rpm will reset fuel trims

Did a little bit of a longer log, just the drive home from work with a few WOT sprints. My LTFT still gets to the -8, -9 area when I'm over 2800 RPMs…think this is safe to run at AutoX on sunday or should I switch back to 93?

[Trettiosjuan]

Originally Posted by Sypher

when i compared them in romraider there is a good chunk of cam timing that is different.

Ok thanks. Any idea of the effect of these differences? Is it trying to fill the dip more with the EL?

Actually pleased with how it runs on the UEL map so should just walk away and enjoy driving it...

[steve99]

[Quote] Did a little bit of a longer log, just the drive home from work with a few WOT sprints. My LTFT still gets to the -8, -9 area when I'm over 2800 RPMs…think this is safe to run at AutoX on sunday or should I switch back to 93? [Quote]

@Silver Ignition
cannot see anything bad in your E85 log
no knock IAM=1 fuel trims probably a bit high and negitive due residual petrol
and if anything its running a bit on the rich side which is safe anyway
should clean up on second and third tanks of "pure" E85
cannot see any reason to switch back to 93.

[tracerit]

Is there an optimal E% to run our cars at? I've decided I'm going to start measuring my ethanol content and mixing the E85 with 91 gas using two 5 gallon gas cans for E85 and one 2.5 gallon can for 91 gas. I've read the ECU and OFT can accommodate E60-E90 but I'm hoping for a tighter variance to run with.

[steve99]

Originally Posted by tracerit

Is there an optimal E% to run our cars at? I've decided I'm going to start measuring my ethanol content and mixing the E85 with 91 gas using two 5 gallon gas cans for E85 and one 2.5 gallon can for 91 gas. I've read the ECU and OFT can accommodate E60-E90 but I'm hoping for a tighter variance to run with.

I would think that shiv did that tune on the average percent of ethanol found in E85 in his area , probably around the middle of that range ie about E70 , this should correspond to where the average LTFT is the least.

You have enough octane rating even at E60 its just the fuel trims will be high.

As we have a guaranteed E85 pump fuel here i just rescaled maf to suit and hence fuel trims around 3%.

[Kelbyat07]

Can someone clarify something for me. When putting E85 to the car for the first time, it is better to fill up with E85 and drive for a little bit and then plug in the OFT for E85 or vice versa; plug in for E85 then put E85. Thanks guys.

[Andrew025]

Originally Posted by Kelbyat07

Can someone clarify something for me. When putting E85 to the car for the first time, it is better to fill up with E85 and drive for a little bit and then plug in the OFT for E85 or vice versa; plug in for E85 then put E85. Thanks guys.

In the first post... Not really sure how to make it any more clear than this.

Originally Posted by steve99

• Run tank down till low fuel light comes on
• Fill with E85
• Plug in OFT to monitor fuel trims (leave petrol tune in at present)
• Drive slowly below 3500 rpm no WOT or hard acceleration until you see STFT rise rapidly followed by LTFT and stay high, this indicates that the petrol is now out of lines and the E85 has made it through the lines and pumps, this generally takes 2 or 3 km
• Pull over and turn off car Flash E85 tune with OFT (Stage 2 EL E85) for stock car or car with EL headers or Stage 2 UEL E85 if you have UEL headers.
• Start car and drive slowly again below 3500 no hard acceleration for next 10 to 20 km until your fuel trims LTFT/STFT stabilise below about 10% while cruising and idle, this allows ECU to learn the E% of your E85 mix.
• If you do flash the E85 map at the pump on switchover the learning process will take longer as the E85 tune will try to learn petrol then when the E85 gets into the system it will need to learn E85.

There are two reasons you need to drive easy

1. To let the ECU learn the new fuel and avoid any damage while its doing so
2. Your ECU only learns fuel trims in Closed Loop mode , this is during cruise and steady or slow throttle movement. During WOT hard acceleration and on/off throttle ECU is in Open Loop mode it does not learn fuel trims just applies what it learns in Closed Loop mode see here for more info http://www.ft86club.com/forums/showthread.php?t=64790


Shiv says the E85 tune is good for mix’s between E60 and E90, but it does take time to learn a new mix , so each time you fuel up take it easy for the first 10km or so to let it learn again.

[Kelbyat07]

Originally Posted by Andrew025

In the first post... Not really sure how to make it any more clear than this.

Yeah I already read that but I just wanted to make sure so I risk ruining my car. Didn't make sense to me that you had to flash after you put E85 in your car...