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

[Lincoln Logs]

This video might be redundant here but I wanted to share it in case it helps anyone. This is my process for switching the tunes, take it with a grain of salt. :-)

[ame="https://www.youtube.com/watch?v=fiodLBN1kSs"]https://www.youtube.com/watch?v=fiodLBN1kSs[/ame]

[pym19109]

Off the topic(maybe?), Does changing the avcs effect E85 mbt ?
Since I have no a real dyno to measure the output and I’m a noob. I’m interested Tor’s gruppe-s avcs (Im running gruppe-s header) because with wayne’s E85 tune I will get knock above 6800 rpm in 3rd gear and worse in higher gear. I pulled timing about 1-2degree to fix that and still get some knock in 4th,5th gear. After I tried Tor’s avcs, there is not knock in 3rd gear with orginal timing and I will let try out the higher gear. Any suggestions?

[steve99]

Originally Posted by pym19109

Off the topic(maybe?), Does changing the avcs effect E85 mbt ?
Since I have no a real dyno to measure the output and I’m a noob. I’m interested Tor’s gruppe-s avcs (Im running gruppe-s header) because with wayne’s E85 tune I will get knock above 6800 rpm in 3rd gear and worse in higher gear. I pulled timing about 1-2degree to fix that and still get some knock in 4th,5th gear. After I tried Tor’s avcs, there is not knock in 3rd gear with orginal timing and I will let try out the higher gear. Any suggestions?

Yes cam timing can effect knock
As well as ignition timing and afr

[steve99]

Originally Posted by Lincoln Logs

This video might be redundant here but I wanted to share it in case it helps anyone. This is my process for switching the tunes, take it with a grain of salt. :-)

Ill link this in first post

[Yoshoobaroo]

Has anyone tried the 4.03 map? Can't find a changelog.

[Tor]

Originally Posted by pym19109

Off the topic(maybe?), Does changing the avcs effect E85 mbt ?
Since I have no a real dyno to measure the output and I’m a noob. I’m interested Tor’s gruppe-s avcs (Im running gruppe-s header) because with wayne’s E85 tune I will get knock above 6800 rpm in 3rd gear and worse in higher gear. I pulled timing about 1-2degree to fix that and still get some knock in 4th,5th gear. After I tried Tor’s avcs, there is not knock in 3rd gear with orginal timing and I will let try out the higher gear. Any suggestions?

When the spark fires, the valves are obviously closed, so I would say that logically the change in AVCS would not affect the values for MBT in a significant way.

I don't know if Shiv's E85 timing is actually MBT or set a bit lower, but if it was me I would simply use Shivs timing. I think the gains are minimal if raising the timing further. If that is what you were getting at?

If you wanted to try anyway, you could make WOT logs with different tunes on the exact same road (and same pressure/temperature - in fact preferably right after another on the same day) and compare using VirtualDyno. You could do the same with the different AVCS settings as well if you wanted to see if you gained any power. I would assume you did - can you feel any difference?

As to why you get less knock, could be a number of reasons. I suppose it has to do with less heat in the combustion chamber. Either more hot exhaust gasses being evacuated or more flow over values in the overlap perhaps. It's, of course, a bit guesswork. Theoretically, it could also be a lower in-cylinder pressure, which would be undesirable and would not correspond with my results in getting more power. Just mentioning it as a factor in general as well.

[pym19109]

I will keep the timing as it was if it doesn’t change mbt value, I don’t really concern about gain 1-2HP but I want to eliminate that knock which should not appear when using E85 right ? So I guess it might be avcs restriction that is not fit for the header.

I don’t trust my butt dyno as Tor said the factors are different and I only have a few time on this tune. My old tune is about 194-197HP depend on the factors. So I’m happy with this number if it no knock(or few) at higher rpm and gear.

Let me try out and I will update the result
Thanks Steve and Tor.

[DrButtDrugs]

How long is it safe to ride around on the incorrect tune when switching fuels?

This question popped into my head when I took a wrong turn out of the only e85 gas station near me and ended up in a mile long tunnel before a shoulder was available. Right after entering the tunnel, of course, my fuel trims starting shooting up. I kept it around 45 mph (in a 55 zone) and didn't break 3k rpm. As soon as I got out of the tunnel I pulled to the shoulder and reflashed the car.

This was a week ago and I know there aren't any problems at this point, but what are the limits of this kind of thing? Is it safer to drive on the e85 tune with 93 in the lines, or 93 tune with e85 in the lines? Any difference? How far is too far?

[ermax]

Originally Posted by DrButtDrugs

How long is it safe to ride around on the incorrect tune when switching fuels?

This question popped into my head when I took a wrong turn out of the only e85 gas station near me and ended up in a mile long tunnel before a shoulder was available. Right after entering the tunnel, of course, my fuel trims starting shooting up. I kept it around 45 mph (in a 55 zone) and didn't break 3k rpm. As soon as I got out of the tunnel I pulled to the shoulder and reflashed the car.

This was a week ago and I know there aren't any problems at this point, but what are the limits of this kind of thing? Is it safer to drive on the e85 tune with 93 in the lines, or 93 tune with e85 in the lines? Any difference? How far is too far?

Going from petrol to E85 on a petrol tune shouldn't be harmful. Going the other way around would be though. When going from E85 back to petrol it would probably be safest to preflash back to a petrol tune before starting the engine. The learning process would be a little delayed but at least you will be safe in the event that you can't find a place to pull over. You could always reset the ECU a little ways down the road after all the E85 is flushed to restart the learning process.

[Lincoln Logs]

Originally Posted by Yoshoobaroo

Has anyone tried the 4.03 map? Can't find a changelog.

I've been running it for quite a while, no changes from the previous 4.0 map other than launch control and flat foot shift. Works great.

Originally Posted by ermax

Going from petrol to E85 on a petrol tune shouldn't be harmful. Going the other way around would be though. When going from E85 back to petrol it would probably be safest to preflash back to a petrol tune before starting the engine. The learning process would be a little delayed but at least you will be safe in the event that you can't find a place to pull over. You could always reset the ECU a little ways down the road after all the E85 is flushed to restart the learning process.

I don't think that's necessary, I've switched back and forth quite a bit without problems. The key is to just drive slow and smooth and I always plan my route so I have a safe spot to pull over too. I've probably switched 10-15 times this year.

[steve99]

Originally Posted by ermax

Going from petrol to E85 on a petrol tune shouldn't be harmful. Going the other way around would be though. When going from E85 back to petrol it would probably be safest to preflash back to a petrol tune before starting the engine. The learning process would be a little delayed but at least you will be safe in the event that you can't find a place to pull over. You could always reset the ECU a little ways down the road after all the E85 is flushed to restart the learning process.

If you drive below 3500 and light throttle you will always be in closed loop fuel mode where ecu reacts instantly to fuel requirements and has enough adjustment to cope with e85/petrol fuel differences.


also the ignition timing changes below 3500 are not large so that keep it fairly safe as well.


Thats the reason i say drive easy light throttle below 3500 in proceedure.


you would not want to go high rpm or get into open loop during changeover period

[steve99]

Originally Posted by DrButtDrugs

How long is it safe to ride around on the incorrect tune when switching fuels?

This question popped into my head when I took a wrong turn out of the only e85 gas station near me and ended up in a mile long tunnel before a shoulder was available. Right after entering the tunnel, of course, my fuel trims starting shooting up. I kept it around 45 mph (in a 55 zone) and didn't break 3k rpm. As soon as I got out of the tunnel I pulled to the shoulder and reflashed the car.

This was a week ago and I know there aren't any problems at this point, but what are the limits of this kind of thing? Is it safer to drive on the e85 tune with 93 in the lines, or 93 tune with e85 in the lines? Any difference? How far is too far?

if you stay below 3500 rpm light throttle you could run a whole tank through car on incorrect fuel.

[Robbierayy1]

Hey I've been running the e85 tune on my stock car and the difference is phenomenal! I was wondering what is the base ethanol percentage that the oft e85 tune is set for? Along with that, does a negative or positive long term fuel trim make the car more powerful or smoother within +-10%? My assumption would be if the car had positive fuel trims after the base tune was applied that it would run better since it would mean there is more ethanol so more fuel is being added which could result in more power. Also more knock resistance with more ethanol! So in the end, which fuel trim would make the car have the best performance in terms of power/speed and smoothness or does it not matter?

[steve99]

Originally Posted by Robbierayy1

Hey I've been running the e85 tune on my stock car and the difference is phenomenal! I was wondering what is the base ethanol percentage that the oft e85 tune is set for? Along with that, does a negative or positive long term fuel trim make the car more powerful or smoother within +-10%? My assumption would be if the car had positive fuel trims after the base tune was applied that it would run better since it would mean there is more ethanol so more fuel is being added which could result in more power. Also more knock resistance with more ethanol! So in the end, which fuel trim would make the car have the best performance in terms of power/speed and smoothness or does it not matter?

OFT tunes will have lowest ltft at around 70-75% ethanol . the will work from about 60-90% ethanol.


On NA cars you achieve max timing MBT at about 60% ethanol content, so on NA cars additional ethanol content (over about 60%) wont allow you to run more timing so it rearly doent doesn't mean more power.


Boosted its different


LTFT % doesn't mean the car is running richer or leaner, LTFT (or stft and ltft together) is the amount of compensation the ecu is applying to the fueling in order to hit the fueling target. So positive or negative fuel trims don't mean the car is running rich or lean .


for that you need to look at commanded afr and actual measured afr.