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Ok guys, hold my hand, im going with an AP and probably e30 tune ! (any advice?) -

Hypergram

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#22
Ethanol Tests kits are like $20 on Amazon. Basically, they're a must. I'm gonna get one, even though mates from my car club reported true E85 last spring, but that could have changed since then. E30 Mix.PNG
 


OP
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Thread Starter #23
Right but if it's not perfectly 30% you will be ok on the canned tunes. i.e. 25-35%

Not speaking against gauges by any means
I refer to the experts here but from what i have read so far, this seems to be the gist. There's a guy on this forum who ran e30 on a stock car/tune and said the car ran fine. Maybe if you are pushing everything to the ragged edge that precision matters more? I'll be as thorough as i can anyway, and i've got some time to figure it all out. AP will be here monday, then i still have to find the tune and install ect.
 


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#25
I refer to the experts here but from what i have read so far, this seems to be the gist. There's a guy on this forum who ran e30 on a stock car/tune and said the car ran fine. Maybe if you are pushing everything to the ragged edge that precision matters more? I'll be as thorough as i can anyway, and i've got some time to figure it all out. AP will be here monday, then i still have to find the tune and install ect.
Call me anytime, but not after 10
 


OP
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Thread Starter #30
These are the measurements you need. These are with perfect ratios mind you, so it'll never be exactly perfect. View attachment 22715
Thanks hyper. I can't help but wonder, what will actually happen if a tad more than 30% is in the tank? Like what if it's 40 or 45? I know the octane isn't the issue, something about the injectors can't move enough liquid since the ethanol needs more liquid volume to burn? But at what point will that be an issue?

I may just get one of those tester kits but what about just saying, ok 51-85% so i'll split the difference and say it averages at 68%, and do calculations based on 68%? Would that be so far off from whatever people are actually getting that it will just go boom?
 


Hypergram

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#31
Thanks hyper. I can't help but wonder, what will actually happen if a tad more than 30% is in the tank? Like what if it's 40 or 45? I know the octane isn't the issue, something about the injectors can't move enough liquid since the ethanol needs more liquid volume to burn? But at what point will that be an issue?

I may just get one of those tester kits but what about just saying, ok 51-85% so i'll split the difference and say it averages at 68%, and do calculations based on 68%? Would that be so far off from whatever people are actually getting that it will just go boom?
I would try to avoid that if possible since I honestly don't know what would happen. I guess if you did the math and calculated the correct percentages it might work, but that might be a question better suited for a tuner.
 


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#32
It's not solely based on octane because the vast majority of the people on this site only have access to 91. E30 mixed with 91 is not the same as E30 mixed with 93. Ethanol also has other advantages it burns at different temperatures and so on.

Sent from my LG-LS997 using Tapatalk
Running an E30 tune or above is solely based on octane content because 91 or 93 mixed with E85 to achieve E30 content allows timing to be advanced beyond what 93 offers. If 91 is only available adding more E85 will achieve the octane rating for an E30 tune to run properly
 


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HBEcoBeaST

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#33
Thanks hyper. I can't help but wonder, what will actually happen if a tad more than 30% is in the tank? Like what if it's 40 or 45? I know the octane isn't the issue, something about the injectors can't move enough liquid since the ethanol needs more liquid volume to burn? But at what point will that be an issue?

I may just get one of those tester kits but what about just saying, ok 51-85% so i'll split the difference and say it averages at 68%, and do calculations based on 68%? Would that be so far off from whatever people are actually getting that it will just go boom?
Your ecu will compensate. You don't get any more power than the tune requests. Our fuel system starts to struggle past e40 on the stock turbo so most tuners don't go past E30 off the shelf. Adding more e85 doesn't get you more power
 


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Thread Starter #34
Your ecu will compensate. You don't get any more power than the tune requests. Our fuel system starts to struggle past e40 on the stock turbo so most tuners don't go past E30 off the shelf. Adding more e85 doesn't get you more power
Ok yea i wasn't really after the power, just the convenience of not having to bust out the scientist beakers every other week. Funny you mention e40 bc i was just watching a video somebody posted on YT and in the comments, the OP says he runs an e40 tune. So clearly 30% isn't our limit and there are people writing tunes for higher than that. He says all he has is a FMIC, intake and catback.
 


HBEcoBeaST

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#35
Ok yea i wasn't really after the power, just the convenience of not having to bust out the scientist beakers every other week. Funny you mention e40 bc i was just watching a video somebody posted on YT and in the comments, the OP says he runs an e40 tune. So clearly 30% isn't our limit and there are people writing tunes for higher than that. He says all he has is a FMIC, intake and catback.
Right I was making a generalization for canned tunes. Custom tunes you can do whatever you want. It's not about the 'limit' of how much ethanol you can run, it's about the overall power and safety.

Your car has to inject a higher volume of e85 than gas so an e40 tune is injecting more fuel than an e30 tune. Eventually fueling can't keep up so there becomes a point of diminishing returns. You can run a higher E blend but you might be making less power if your injectors can't keep up.
 


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Thread Starter #36
Right I was making a generalization for canned tunes. Custom tunes you can do whatever you want. It's not about the 'limit' of how much ethanol you can run, it's about the overall power and safety.

Your car has to inject a higher volume of e85 than gas so an e40 tune is injecting more fuel than an e30 tune. Eventually fueling can't keep up so there becomes a point of diminishing returns. You can run a higher E blend but you might be making less power if your injectors can't keep up.
Ok makes sense. So if a person split the difference and tuned for e30, and fueled up with a ratio assuming the average of 68%, what is the worst that can happen? Running slightly lean if the e85 pump offers 85%, and running rich if it offers 51% ? But either way you are only going to be off by 17% at most, and with the randomness of the universe, more often than not, less than that. Is that catastrophic, a maximum 17% swing?

Not saying i will do it that way but i just like to know limits when learning things.
 


HBEcoBeaST

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#37
Ok makes sense. So if a person split the difference and tuned for e30, and fueled up with a ratio assuming the average of 68%, what is the worst that can happen? Running slightly lean if the e85 pump offers 85%, and running rich if it offers 51% ? But either way you are only going to be off by 17% at most, and with the randomness of the universe, more often than not, less than that. Is that catastrophic, a maximum 17% swing?

Not saying i will do it that way but i just like to know limits when learning things.
Our ECU does a great job of measuring fuel needs several times a second. It will automatically sense the fuel difference and adjust according to the target power range.

Our ecus from the factory can automatically sense if you full with 87 vs 93. You don't hurt anything on 87, but it makes more power on 93 since it's optimized for that even though it's the same 'tune'. The same system is just optimized for E30 with a canned tune. It will adjust for the fuel ratio.
 




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