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Discussion Starter #1
1st, if you are going to post “facts” from Googling, at least do it from a scientific source. @nd, if you haven’t actually used them, it may be a good idea to listen for a bit B4 posting. And if you flatly refuse to use ANY gas with alcohol, please go to one of the 16mm vs. 19mm SB threads. 😊
Pretty much every station where I live offers E10 and have dropped alcohol free gas. Both were/are 87 octane here. They used to have an intermediate gas between “regular” and “premium” at 89 octane priced half way. Premium was anywhere from 91 to 93. The 89 octane gas has disappeared and most now offer E15 in it’s place. I’ve used all, although 85 octane is not available where I live, I have used it plenty while travelling out west. I have only used E15 recently, having a “what the H” moment after seeing it was 5 cents cheaper than E10. E15 should be priced 2 cents cheaper based on energy content according to reliable sources, so I was saving a bundle (wink).
After using it a while I really don’t see any difference in performance or gas mileage between E10 or E15. Modern engines adjust to the fuel right? This might shock some but I almost always use E10 in my 2007 Corvette. I use it mainly as a long distance touring car, so gas mileage is more important than eeking every last HP out of it. Besides, do the math, whatever the HP reduction is, say 15% of 400 is still a lot of HP. I stopped using premium for it when the price went thru the roof, there were a couple gas stations selling it for only 12-14 cents a gallon more than regular, so that was a no brainer. But now that it’s 70-80 cents, and sometimes more, it is just wasted money. And BTW, even using 85 octane running thru mountain passes or E10 at home I still smoke the go-faster wannnabees.
I also tried E15 in the Vette, about 5 gallons in a near empty tank, also with no apparent difference, although a one time use doesn’t say much. And no, every seal and electrical connection did not fail.
I think I will continue to use E15 in the OB, I’ll talk about why in a later post.
As far as 85 octane regular goes, my gas mileage INCREASES, but that’s probably due to travelling at higher elevations and the mixture leaning out. I find this happens whether I was/am using my 92 HP Mazda B2200 pickup, OB, or Vette. Most vehicles are set to burn too rich a mixture, this helps longevity, IOW, the manufacturer experiences less engine work.
Anyway, would like to hear your EXPERIENCE using these fuels.
Don’t bother repeating what you read on the internet, or what a friend of a friend says, I know how to Google too.
 

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So long as your vehicles are compatible with E15, run what you like and you get what you get. ;)
Where I live, we've been running on E10 for years. Fortunately, our vehicles are okay to run E10, but no more than that so thanks for the reminder that some stations are starting to offer E15. I'll have to keep my eye on that and be sure I don't get that by mistake.
 

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I don’t see a big deal between e10 or e15 as long as you use the recommended octane, 87. The only downsides to the ethynol fuels is water absorption.
I wouldn’t risk running 85 octane especially if your car is under warranty or service contract. And I wouldn’t waste money in 89 or higher as there is no documented evidence of performance gain as we do not have high compression or turbo charged motors.
In the end, it’s your car so run what ever gas makes you happy.
 

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Discussion Starter #4
90% of the gas sold in CO is 85 octane, so people are voting with their wallets. I believe it is only sold in CO, MT, WY, & UT. Many stations do not sell 87 octane gas because nobody wants it. So if there is something wrong with using 85 octane, you'd think these states would have higher than normal engine breakdowns.
I have never noticed pinging coming from my engine while using it. You'd think with all the elevation gains, somewhere along the line I'd notice pinging.
When I am leaving these states, it is downhill usually with the wind at my back, so the engine isn't working hard. In my Vette, 80mph is 2000 rpm, so its barely working. I usually fill up in Hudson with 85 and again just across the Iowa line from Omaha with 87.

I read a report on a study that looked at various mixtures of alcohol, there was no significant difference between E10 & E15, higher % there was a difference and they said only use in flex fuel vehicles. Actually the water in alcohol in small amounts is not only unavoidable, it is a good thing because it sucks up the impurities in the mix (kinda like alcohol taking in water) that would otherwise collect and eventually clog the system.
None of my vehicles is under warranty, so not a factor.
 

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When I was in Colorado last year, I was able to fill up with 87 no problem. It was the mid grade as you said 85 is regular. With my Hemi in Colorado I fill with premium, or 91, as there is no 89 which is required. Always best to go with what the manufacture recommends unless you are smarter then their engineers. Again, it's your car, it's your choice.
 

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I was all about premium gas since has beneficial additives and my cars have generally been higher compression performance type. However, except for the occasional tankful of premium my 3.6L OB gets plain 87 octane and 10% ethanol.

No noticeable performance benefits to 93 octane. 🤷🏻‍♂️
 

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Brucey
'17 3.6
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I ran E0 while in Michigan last year. No noticeable performance or MPG gain. In fact it reported slightly lower MPG even under similar conditions. I'm sure it's not worth the extra cost.

(Mostly highway 70-75 mph cruising)

Other than that it's just E10 87 Octane.
 

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Discussion Starter #9
When I was in Colorado last year, I was able to fill up with 87 no problem. It was the mid grade as you said 85 is regular. With my Hemi in Colorado I fill with premium, or 91, as there is no 89 which is required. Always best to go with what the manufacture recommends unless you are smarter then their engineers. Again, it's your car, it's your choice.
While I agree that you should go with what the MFG recommends:
1) Many stations I have stopped at do not offer 87 octane, it's either regular or premium, and if there are more selections, it's usually diesel or alcohol free, although yeah, some offer 87, but if it isn't available and you need gas ....
2) so why don't these states have a higher than normal engine breakdown rate? as I mentioned, 90% of the gas sold in CO is 85 octane
3) the reason 85 is sold is because tests showed that 85 octane is sufficient at high elevations, re-read #2
 

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Sorry, gasoline + ethanol has a LOWER combustion rate than straight gasoline. Also, that combination actually provides LOWER fuel economy than straight gasoline.
It’s all about subsidized corn.

BTW, if it was ”better” race teams would be all over it but they are not unless forced to for marketing reasons.
 

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Interesting discussion. I'll relate (again) the experience I had with E10 and E0 fuel my 2000 V6 Camry (with 5-speed MT!)

When it was new, I was getting mileage around 27 mi/gal on a tank when the bulk of the driving was my daily 12 mile, twice a day commute, about half on free-flowing highway and the rest not terribly congested city driving, with short lunch trips and a few putz-around-town trips, filling up about once every two weeks. This was very repeatable over a span of years. Then, I noticed that I was no longer getting that mileage - it had dropped rather abruptly to between 24 and 25 mi/gal for several tankfuls with the same driving pattern, and stayed there.

A while later I had forgotten to get gas when I meant to, and was at lunch with a nearly-empty tank. The mom-and-pop gas station next door had a sign "100% Gas! No Ethanol!" It cost more (20¢/gal, as I recall, less than 10% higher) but I really needed to fill up and get back to work, so why not? The mileage from that tank was back to 27 mi/gal. Hmmm... that's interesting.

Next time, I had filled at the usual place, noted the "May contain up to 10% Ethanol" sticker on the pump, and got about 25 from that batch. Filled with E0... 27. Filled with E0 again, and again got 27. At this point I started to routinely use E0 if practical, and the mileage stayed at 27 for those routine tanks, dropping consistently by about the same amount when I did use E10. I was literally getting 8 to 10% better mileage with the Ethanol-free gas, and noticed that the car seemed to like it better - it ran smoother - too, for a price around 8 to 10% higher. This went on for several years until the price of E0 increased rapidly to about 40¢ over E10, at which point it no longer made economic sense to me, and I mostly quit using it.

When I traded the Camry in for the 2015 Outback, I tried a few tanks of E0, even at the much higher cost, but did not notice any change in mileage at all. By then I was retired and my driving pattern was much more varied, so the tank-to-tank consistency was gone. Still, over several tanks I was pretty sure I'd see a difference if it was as large as with the other car, but nada, so I never use the stuff now.

I'm not sure what it was about that Camry, but it did not like gasoline with Ethanol, and for a while E0 was priced so that it was a no-brainer! YMMV.
 

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Chiming in with my extremely limited experience... driving across the country in a heavily laden Chevy minivan, maybe 12 years ago. Arrived in the Mountain west and was surprised to see 85 octane on offer as "regular".

Now I know enough of the science behind automotive combustion to understand that high altitude equates to lower required octane, and they were selling it as "regular" (and I was driving a rental!) so I figured WTH and filled 'er up.

Hopped back on the freeway and the first thing I noticed was high RPM at cruising speed. I double checked the shifter and confirmed I had it in the right place, but the van wouldn't shift into overdrive!

Of course the MPG went in the toilet as well.

As soon as we were able to burn off a significant fraction of that tank we filled up with super and the problem more-or-less went away.

Maybe I got a bad tank? I dunno, but since then I've avoided 85.

Incidentally, where are they selling E15 in place of mid-grade? I haven't seen that around the PNW.
 

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I can also attest to this. I had a 2004 Suburban that I drove on long hwy trips for my business. Unless I was pushing it I always averaged around 20 MPG. Go forward a few years and all the sudden my MPG's dropped. Driving the same way I was struggling to get 18 MPG. Changed spark plugs, etc. No change. Then I found out almost all the gas that was available to me was E10. GRRRRR! I'm still so anti ethanol if I was a terrorist there would not be an ethanol plant in this country that was not smoldering. Add to that making all my small engine yard tools throw away every year or 2 as the stinking fuel system parts are priced through the moon. Ever priced 1 of those little primer bulbs ya pump to start 1? Should a dollar part, last time I priced 1 it was $15.00!

Interesting discussion. I'll relate (again) the experience I had with E10 and E0 fuel my 2000 V6 Camry (with 5-speed MT!)

When it was new, I was getting mileage around 27 mi/gal on a tank when the bulk of the driving was my daily 12 mile, twice a day commute, about half on free-flowing highway and the rest not terribly congested city driving, with short lunch trips and a few putz-around-town trips, filling up about once every two weeks. This was very repeatable over a span of years. Then, I noticed that I was no longer getting that mileage - it had dropped rather abruptly to between 24 and 25 mi/gal for several tankfuls with the same driving pattern, and stayed there.

A while later I had forgotten to get gas when I meant to, and was at lunch with a nearly-empty tank. The mom-and-pop gas station next door had a sign "100% Gas! No Ethanol!" It cost more (20¢/gal, as I recall, less than 10% higher) but I really needed to fill up and get back to work, so why not? The mileage from that tank was back to 27 mi/gal. Hmmm... that's interesting.

Next time, I had filled at the usual place, noted the "May contain up to 10% Ethanol" sticker on the pump, and got about 25 from that batch. Filled with E0... 27. Filled with E0 again, and again got 27. At this point I started to routinely use E0 if practical, and the mileage stayed at 27 for those routine tanks, dropping consistently by about the same amount when I did use E10. I was literally getting 8 to 10% better mileage with the Ethanol-free gas, and noticed that the car seemed to like it better - it ran smoother - too, for a price around 8 to 10% higher. This went on for several years until the price of E0 increased rapidly to about 40¢ over E10, at which point it no longer made economic sense to me, and I mostly quit using it.

When I traded the Camry in for the 2015 Outback, I tried a few tanks of E0, even at the much higher cost, but did not notice any change in mileage at all. By then I was retired and my driving pattern was much more varied, so the tank-to-tank consistency was gone. Still, over several tanks I was pretty sure I'd see a difference if it was as large as with the other car, but nada, so I never use the stuff now.

I'm not sure what it was about that Camry, but it did not like gasoline with Ethanol, and for a while E0 was priced so that it was a no-brainer! YMMV.
:devilish:
 

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Sorry, gasoline + ethanol has a LOWER combustion rate than straight gasoline. Also, that combination actually provides LOWER fuel economy than straight gasoline.
It’s all about subsidized corn.

BTW, if it was ”better” race teams would be all over it but they are not unless forced to for marketing reasons.
And what class is the Principle investor in these agra corn factories? Members of the U.S. Congress.
 

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Discussion Starter #16
several of you have related how there was a difference in MPG, OK, however, one of you was comparing a 2000 Camry, another a 2004 Suburban, those cars likely weren't designed to run on E10, the Gen 5 Outback was designed 15-20 years later and likely to use E10, modern cars adjust to the fuel used, that is a FACT

and the guy that posted his RPM were higher after filling with 85 octane , NOT POSSIBLE, a figment of your imagination

I also notice a couple of you are posting THEORY of E10/E15 vs. E0, but fail to disclose any EXPERIENCE with the comparison

lastly, I have not been able to find ANY evidence of increased breakdown in vehicles where 85 octane gas is sold, DO YOU HAVE ANY EVIDENCE OF THERE BEING AN INCREASE?
 

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Discussion Starter #17
FYI, here is the data for when MFG approved E15 in ALL of their vehicles

GM since 2012
Ford since 2013
Chrysler since 2016
Toyota since 2016
Volkswagen since 2014
Porsche since 2015
Audi since 2014
Jaguar/Landrover since 2014
Honda/Accura since 2015

Subaru only in the Ascent, Xrosstek, and Impreza since 2019
 

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several of you have related how there was a difference in MPG, OK, however, one of you was comparing a 2000 Camry, another a 2004 Suburban, those cars likely weren't designed to run on E10, the Gen 5 Outback was designed 15-20 years later and likely to use E10, modern cars adjust to the fuel used, that is a FACT

and the guy that posted his RPM were higher after filling with 85 octane , NOT POSSIBLE, a figment of your imagination

I also notice a couple of you are posting THEORY of E10/E15 vs. E0, but fail to disclose any EXPERIENCE with the comparison

lastly, I have not been able to find ANY evidence of increased breakdown in vehicles where 85 octane gas is sold, DO YOU HAVE ANY EVIDENCE OF THERE BEING AN INCREASE?
Are you from Missouri? 😀
 

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...
Anyway, would like to hear your EXPERIENCE using these fuels.
Don’t bother repeating what you read on the internet, or what a friend of a friend says, I know how to Google too.
several of you have related how there was a difference in MPG, OK, however, one of you was comparing a 2000 Camry, another a 2004 Suburban, those cars likely weren't designed to run on E10, the Gen 5 Outback was designed 15-20 years later and likely to use E10, modern cars adjust to the fuel used, that is a FACT
...
You asked about people's EXPERIENCE using these fuels. I related my experience with the 2000 Camry. I also reported that it did not seem to be the same for the 2015 Outback, and the difference was significant. If you weren't interested in hearing about experiences when the different fuels DID make a difference because the cars were older, you should have been more clear.

Chill, dude!
 

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... one of you was comparing a 2000 Camry, another a 2004 Suburban, those cars likely weren't designed to run on E10 ...
E10 has been widely available since the early 1980s. My 1988 Pontiac Fiero, 1991 Buick Regal, and 1993 Dodge Caravan were all approved for E10 use by the manufacturers when new; my 1988 Dodge Caravan was a flex-fuel vehicle, approved for E0, E10, or E85.

... modern cars adjust to the fuel used, that is a FACT
Agreed, but there are limits to the range of adjustment. It is also a FACT that the energy content of E10 (per unit volume) is about 3% less than "pure" gasoline. (Source: U.S. EPA) That translates to about 0.7 to 1 mpg difference in our Subarus, just due to energy content alone.
 
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