88 octane unleaded without ethanol less expensive than 87 octane with ethanol?

TiGeo

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At least for me, I've never claimed it to be a giant percentage. Once you've run enough E15 vs E10 and have records, its easy to see that I do get lower fuel mileage on E15. Statistically, its almost 2% lower. I'll also note that despite the higher octane rating, my truck doesn't see it that way and actually reduces the timing etc... on E15. Not just as simple as energy content.

So for me, at current prices of 3.99 a gallon for 87 E10, if E15 is more than about 8 cents a gallon less, then it makes sense to run. Many stations here are only 3 cents cheaper a gallon through...
How are you determining the timing advance/knock correction? Is this apples to apples i.e. do you see this year around with both summer and winter fuels? It would make sense to see summer 87 perform better than winter 88.
 
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On a ford ecoboost there is a parameter called the Octane Adjustment Ratio (OAR). It is a measure of what the engine perceives the octane to be based on its monitoring of things like knock. It ranges from-1.0 (good) to 1.0 (bad). I've monitored this for over 5 years on my 2016 F150.

On local fuels, e10 and e0 premium will get me over -0.7. Regular 87 E10 is typically 0 to -.2. E88 is routinely 0.3 to 0.1.

No trend to time of year that I have noticed, and I have more than enough records at this point.
 
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Kwik Trips around here that are within a few miles of each other, vary widely. I personally don't use E88, unless it is .25c less than 87. Just my personal choice.
I haven't noticed a difference in mileage or performance between 87(E10) or 88(E15) in my 2006 Ford Focus or 2019 F-150 5.0 (Flex Fuel). I wouldn't use it in a boat or small engine though just for longevity of the fuel reasons.
 

TiGeo

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On a ford ecoboost there is a parameter called the Octane Adjustment Ratio (OAR). It is a measure of what the engine perceives the octane to be based on its monitoring of things like knock. It ranges from-1.0 (good) to 1.0 (bad). I've monitored this for over 5 years on my 2016 F150.

On local fuels, e10 and e0 premium will get me over -0.7. Regular 87 E10 is typically 0 to -.2. E88 is routinely 0.3 to 0.1.

No trend to time of year that I have noticed, and I have more than enough records at this point.
Very interesting!
 
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Wouldn't you know it, my area's not listed at all...
Do you have Circle K gas stations ? They sell it. Otherwise, most locations will be a random "franchise" gas station or boat marina gas stations. Caseys seems to be getting out of selling it.
 
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Do you have Circle K gas stations ? They sell it. Otherwise, most locations will be a random "franchise" gas station or boat marina gas stations. Caseys seems to be getting out of selling it.
Not if your area is an EPA designated nonattainment area as are many metropolitan cities. Here in the five-county southeastern Wisconsin corridor no station can sell E0 and neither does the Milwaukee Marina.
 
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Not if your area is an EPA designated nonattainment area as are many metropolitan cities. Here in the five-county southeastern Wisconsin corridor no station can sell E0 and neither does the Milwaukee Marina.
I don't know where he lives or if that applies in his area, so he could check (I put little value in those pure-gas.org maps as to being up-to-date anyway).
 
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If you’re near I-35, there’s the Buc-ee’s in Melissa, TX or the Red River Co-op in Gainesville, TX. The QuikTrip chain has been expanding rapidly in Texas and May have some North Texas stations. I’m less familiar with west Texas, but a quick map check on my Pure Gas app shows a chain called “Toot n’ Totum” around Amarillo and a Murphy Express in Lubbock, as well as independent fuel companies scattered throughout that might have banker’s hours.
Thanks man. I live in Arlington. They built a new QT down the street and doesn’t have it.
 
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I

And the most you could lose is 5% running E15 vs E10.
Probably correct in a light car. But towing, i needed a touch more throttle angle, and on slight grades, it caused the trans to downshift to the next gear. I was hoping it would not be that much different towing , since it had 1 point more octane. But i definitely dropped from 11.4 to 8.9.

Not calculated, but by the dash estimate. I've made the same trip a few times, and no doubt burned more than 5% more towing.
 
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Probably correct in a light car. But towing, i needed a touch more throttle angle, and on slight grades, it caused the trans to downshift to the next gear. I was hoping it would not be that much different towing , since it had 1 point more octane. But i definitely dropped from 11.4 to 8.9.

Not calculated, but by the dash estimate. I've made the same trip a few times, and no doubt burned more than 5% more towing.
Then why do engines make more HP on E85? I know they get less mileage, but I don't think you lose power?
 
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Probably correct in a light car. But towing, i needed a touch more throttle angle, and on slight grades, it caused the trans to downshift to the next gear. I was hoping it would not be that much different towing , since it had 1 point more octane. But i definitely dropped from 11.4 to 8.9.

Not calculated, but by the dash estimate. I've made the same trip a few times, and no doubt burned more than 5% more towing.

Possible that you had more than E15 in there. Sometimes a "blending error" happens. Not supposed to, but it does. Most vehicles will run up to about an E40 blend before they'll set a lean code. I've run a 50/50 blend of E10 and E85 in my cars before with no problem other than lower fuel economy.
 
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It's NOT recommended by Honda. Only use e10 or less. The 88 octane part would be okay but the 15 percentage of corn is a no go.

Newer models are approved. There might even be backdated approvals, like how Honda backdated 5W-20 approval.

We recommend quality gasoline containing detergent additives that help prevent fuel system and engine deposits. In addition, in order to maintain good performance, fuel economy, and emissions control, we strongly recommend the use of gasoline that does NOT contain harmful manganese-based fuel additives such as MMT, if such gasoline is available.​
Use of gasoline with these additives may adversely affect performance, and cause the malfunction indicator lamp on your instrument panel to come on. If this happens, contact a dealer for service.​
Some gasoline today is blended with oxygenates such as ethanol. Your vehicle is designed to operate on oxygenated gasoline containing up to 15% ethanol by volume. Do not use gasoline containing methanol. If you notice any undesirable operating symptoms, try another service station or switch to another brand of gasoline.​
 
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Then why do engines make more HP on E85? I know they get less mileage, but I don't think you lose power?

E85 is something like 105+ AKI. Timing gets advanced and it’s far more efficient with respect to energy content. But more gasoline means higher fuel economy, but possibly less timing advance and lower performance. If one used 105 octane gasoline without an oxygenate, it would result in performance and incredible fuel economy.
 
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Then why do engines make more HP on E85? I know they get less mileage, but I don't think you lose power?
Ethanol has a nice cooling effect, coupled with the high octane allows you to push the timing pretty hard. I remember watching an episode of Engine Masters where they tested E85 vs equivalent octane race gas. They ended up making just about the same power and torque, but the E85 was more forgiving and had a “wider” tuning window.
 

grampi

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Do you have Circle K gas stations ? They sell it. Otherwise, most locations will be a random "franchise" gas station or boat marina gas stations. Caseys seems to be getting out of selling it.
We don't have any Circle Ks here, but after doing a bit of research, it appears that some of the Marathon, Meijer, and Sunoco stations sell it. I'll just have to locate the ones that do...
 
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I doubt that "some" Meijer stations sell it. They all sell the same and I've never seen it at a Meijer. They sell gas purely as a convenience to their customers, not for offering variety and choices of fuel.
 

TiGeo

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Then why do engines make more HP on E85? I know they get less mileage, but I don't think you lose power?
B/C the car is tuned for it - and by tune that typically means more boost/more timing advance b/c you have much more knock/det resistance with ethanol (plus burns cooler). If your car isn't tuned for it I can't see you'd get much out of running it - you'll use more volume of fuel so get crappier mpgs but you aren't paying as much per gal - just a math exercise.

Take my car - I run an aftermarket software tune based on 93. I run some E85 to get a 20-25% ethanol content. I log my car all the time and see several more degrees of timing advance (plus cooler combustion!) at WOT redline running the E blend with no adverse effects w/r to running out of fuel (pumps tapped out). It's magical!
 
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