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

[jz_JDM]

Originally Posted by steve99

Hmmm -12% ltft is a little high but if your E85 is low ethanol content some stuff in USA is now around 50%. Combined with the probably 10 litres of residual petrol in tank on first fill that ltft of -12 is probably correct.


low ethanol content will see negative fuel trims
high ethanol content above about E75 will see positive


Just take it a bit easy till you fill with E85 again this should see the fuel trims get much less negative.

Okay sounds good! I'll see how it looks after my next fill up. Will there be any negative effects from having the ltft that high for a week or two?

[carsebuco]

Originally Posted by HLHachiRoku

Noticed you're from AZ. There is no E85 in arizona any longer. Unless you are buying the drums and pumping it at your house. So you will always have the negative trims like that. AZ has e51-70 roughly now, called flex fuel at the pumps, might see a bit higher but unlikely. Any station listing they hve e85 is lying to you or still has it mislabeled. AZ legislature last aug passed this law sadly, we got screwed. You can still run the e85 tune but it wont be as good, the ethanol content ive noticed on this side of town, west side, sits around 53-64 usually. Ive retuned for it and have had great results so far, more data logging today to see how its doing.

I'm new to AZ and just switched to e85 a few weeks ago. My LTFT stays at around - 10% and it's quite sad to see, but it's still a great improvement from 91 octane.

[jz_JDM]

Originally Posted by steve99

Hmmm -12% ltft is a little high but if your E85 is low ethanol content some stuff in USA is now around 50%. Combined with the probably 10 litres of residual petrol in tank on first fill that ltft of -12 is probably correct.


low ethanol content will see negative fuel trims
high ethanol content above about E75 will see positive


Just take it a bit easy till you fill with E85 again this should see the fuel trims get much less negative.

Okay sounds good! I'll see how it looks after my next fill up. Will there be any negative effects from having the ltft that high for a week or two?

[jz_JDM]

Originally Posted by carsebuco

I'm new to AZ and just switched to e85 a few weeks ago. My LTFT stays at around - 10% and it's quite sad to see, but it's still a great improvement from 91 octane.

Really? I don't notice a huge difference after switching. Perhaps its because I'm only on my first tank of this...

[carsebuco]

Originally Posted by jz_JDM

Really? I don't notice a huge difference after switching. Perhaps its because I'm only on my first tank of this...

Before I went the e85 route I had to drop down from 93 to 91 because of AZ. It was my third tank when I was in the highway here and downshifted to 4th to pass someone and the car barely moved the first few seconds. That's when I knew I couldn't take 91 anymore. Now, however, everything is smooth. Hell, I can even pass in 6th gear.

[chazmuska]

Originally Posted by HLHachiRoku

Noticed you're from AZ. There is no E85 in arizona any longer. Unless you are buying the drums and pumping it at your house. So you will always have the negative trims like that. AZ has e51-70 roughly now, called flex fuel at the pumps, might see a bit higher but unlikely. Any station listing they hve e85 is lying to you or still has it mislabeled. AZ legislature last aug passed this law sadly, we got screwed. You can still run the e85 tune but it wont be as good, the ethanol content ive noticed on this side of town, west side, sits around 53-64 usually. Ive retuned for it and have had great results so far, more data logging today to see how its doing.

Do you know where in AZ I can at least get e70? I go to the one on Pecos and Higley and theirs is like e55, so I'm getting really low LTFT as well! I want to see how we can overturn that AZ law!

[Mr Nerd]

Originally Posted by chazmuska

Do you know where in AZ I can at least get e70? I go to the one on Pecos and Higley and theirs is like e55, so I'm getting really low LTFT as well! I want to see how we can overturn that AZ law!

You will not find e85 in Arizona as of 2015. Don't ask why.

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[chazmuska]

Originally Posted by Mr Nerd

You will not find e85 in Arizona as of 2015. Don't ask why.

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Is there a way to increase the ethanol content? Like dumping a bottle of Everclear with half a tank of e55? I'm totally kidding...well maybe not!

[Mr Nerd]

Originally Posted by chazmuska

Is there a way to increase the ethanol content? Like dumping a bottle of Everclear with half a tank of e55? I'm totally kidding...well maybe not!

Try it. Most people don't understand how combustion works. With the proper tuning adjustments you can run off French fry oil of you really wanted too.

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[alestrada]

Alright Steve, Ive been working with HLHachiRoku and he has done quite a bit for me setting up a flex tune for the 53 we have in Arizona. I believe he might have gotten pretty busy, and even though I appreciate his hard work, I would really like to see if I can fix this rich problem I have going on. Ive been dipping into the high 10s. I would like to draw more power out of it. Ive been comparing his first tune to the v2 of it and the original 85 tune from oft to try and figure it out. He was able to rid of knock during cruising speeds. So now the focus is leaning out the WOT to achieve a little more power. Hopefully I am not wrong, I feel as though I might have to up the flow above the 3.0v on the maf scaling or am I looking at the Open Loop Scaling and uping the target afr about 4k rpm with an engine load of >1. Let me know what you think I should look at when you get the chance!

http://datazap.me/u/alestrada/wot-2nd-tune?log=0&data=1

[mizzta21]

Hi, noob here, I'm running stage 2 e85 on my 86 with stock headers and intake. Would I get the most gains using the stage 2 maf scale it comes with, or should I copy the stage 1 maf scale into the stage 2 e85 tune? Reason I ask is because sometimes I feel more pep top end in a stage 1 tune compared to stage 2, thanks!

[steve99]

Originally Posted by mizzta21

Hi, noob here, I'm running stage 2 e85 on my 86 with stock headers and intake. Would I get the most gains using the stage 2 maf scale it comes with, or should I copy the stage 1 maf scale into the stage 2 e85 tune? Reason I ask is because sometimes I feel more pep top end in a stage 1 tune compared to stage 2, thanks!

Use the stage 2 e85 tune , log and see what afr it running top end, then adjust maf scaling to bring the afr and commanded afr to be same

[-Willis-86touge]

So I've just recently put e85 in. First time, and started initially looking at values and the biggest question I have is afr is at around 14.5-11.5 depending on crusing or wot. Why from everything I can understand stoichiometrich is around 10.5 for e85 and optimal power around 9??? This seems way to much of a difference. Can anybody explain why? Does it just read wrong and we compensate for that or is something else going on. Even at 11 we still would be running lean??

[steve99]

Originally Posted by -Willis-86touge

So I've just recently put e85 in. First time, and started initially looking at values and the biggest question I have is afr is at around 14.5-11.5 depending on crusing or wot. Why from everything I can understand stoichiometrich is around 10.5 for e85 and optimal power around 9??? This seems way to much of a difference. Can anybody explain why? Does it just read wrong and we compensate for that or is something else going on. Even at 11 we still would be running lean??

Correct , but all is ok. The ecu does not know your running e85 and neither does the 02 sensor. The ecu does all its calculation reliative to petrol afr, and theirs a lot of stuff hard coded in ecu ie petrol stoic at 14.7. To chamfe this would be very difficult, but you dont need to.

The 02 sensor just reads amount od 02 it doesnt read afr it reads lambda. So if it reads stoic or lamda 1 thats what it tells ecu, as ecu is set up ie calibrates the reading for stioc to petrol afr the ecu will convert lamda 1 from o2 sensor to 14.7 petrol afr.

Its does this regardless of it your running petrol or e85.

However you do need 30% more fuel to achieve stioc on e85 than you do on petrol so again you fool the ecu by moding the port injector scaling and di pressure targets in case of oft or ecutek mod the overall fuel multiplier by 30%.

All this means is that the ecu thinks its on petrol but its actually running e85 so all the afr reported by ecu are petrol afr but its rearly running e85 afr