Ethanol free gas

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CT8

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Has any one used Ethanol free gas and noticed an increase in mpgs? It is so hard to actually prove a mpg increase but on the dash read out and doing the math, I am seeing about a 1 mpg increase over 3 tanks. I will run a few more tanks fulls and see if the mpgs stay up though.
 
Yep, when in Oklahoma my wife and I filled up her Prius with ethanol free and got 4.5mpg more than usual for a few fill ups. Once back in TX and Ethanol the mileage went back down.
 
The only ethanol FREE gas in my area is 93 octane, or whatever high octane the stations carry. My vehicle don't require octan this high. I supposed I could use it in the Firebird FORMULA(I do use 91-93 w/10% e) in my signature but otherwise, I'm staying with 87 octane w/10% ethanol.
 
I was just reading a bunch of articles on this last night. One qouted ethanol free vs 10percent ethanol had about 1.6 percent less energy by volume. I guess that can translate to 4.7 at the wheel. (Besides energy density I am sure it also affects energy conversion)
 
I don't have my logs anymore but when I got my 2014 Altima 2.5L I had done a few tests.

1) I always filled up at the same WaWa
2) I never filled up until my gas light was on
3) I changed my oil regularly with the same Mobile1 0w20 every 7K.

While doing this I drove a number ofn tanks(some place from 5-7, I don't recall anymore) on 87oct and then the same number on 89oct. During this time 89 was priced closer to 87 than 91 or 93.

I found that the MPG on 89 was so much better than on 87 that using 89 was actually cheaper in the price-per-mile average over all the tanks. 89 was slightly better than 87 on the first tank then on the 2nd it went up more and then the rest of the tanks were right in line or just slightly better than the 2nd. This continued until 89 had like a 5-10 cent jump and moved closer to premium prices. Then 87 was cheaper again. When on 89 the car was also very mildly smoother with a bit less vibration.

My driving was always the same for work. This was during spring to fall on 2014, I then re-did it for the same time period on 2015 and had similar results regarding the MPG increase, but due to 89oct being priced higher It wasn't beneficial to keep running it despite my MPG increasing.

There were 2 things that I could see that caused this, and were possibly related.
1) The cars ECU was actively pulling a tiny bit of timing at all times. The higher octane was letting it stop pulling that timing(or less of it) which resulted in smoother operation and allowed for the MPG increase.
2) I heard(never found any proof) 87oct was/is using a lower oct of "real gas" then adding in E to reach 87. The 89 was using a higher base of "real gas" and then adding in E to make 89. The fact the 89 had a higher base octane of "real gas" was better for the car, because automakers still use "real gas" 87 in their testing and not e10. ----- again no evidence on this one, but something I heard and seemed to possibly be logical.
 
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Any modern vehicle will adjust timing based on increased octane. Unless you're direct injection or FI or some combination of the two, it's a small difference.

My parents' last escape (2.0T EB 2013) went from ~23 to ~27 going from 87 with ethanol to 91 ethanol free. Probably more of it was from using higher octane gas but the lack of ethanol probably played some part of it.
 
Originally Posted By: Jooksing
I was just reading a bunch of articles on this last night. One qouted ethanol free vs 10percent ethanol had about 1.6 percent less energy by volume. I guess that can translate to 4.7 at the wheel. (Besides energy density I am sure it also affects energy conversion)


That's basically BTU's per gallon. Gasoline is about 114,000 btu's per gallon and ethanol is 76,100. Do the math and 10% ethanol works out to about 102,600 btu from gas and 7610 from ethanol for a total of 110,210 per gallon vs the 114,000 in pure gasoline. So gas mileage will be about 3.3% worse with 10% ethanol.

That's why E85 is no bargain even if it's much cheaper than gasoline. Just doesn't have the btu's that gas has.
 
Originally Posted By: BullittGT

2) I heard(never found any proof) 87oct was/is using a lower oct of "real gas" then adding in E to reach 87. The 89 was using a higher base of "real gas" and then adding in E to make 89. The fact the 89 had a higher base octane of "real gas" was better for the car, because automakers still use "real gas" 87 in their testing and not e10. ----- again no evidence on this one, but something I heard and seemed to possibly be logical.


I am tempted to try this to "measure" how much e was added.

https://www.youtube.com/watch?v=RbDAw4a6Ck0
 
Originally Posted By: Wolf359
Originally Posted By: Jooksing
I was just reading a bunch of articles on this last night. One qouted ethanol free vs 10percent ethanol had about 1.6 percent less energy by volume. I guess that can translate to 4.7 at the wheel. (Besides energy density I am sure it also affects energy conversion)


That's basically BTU's per gallon. Gasoline is about 114,000 btu's per gallon and ethanol is 76,100. Do the math and 10% ethanol works out to about 102,600 btu from gas and 7610 from ethanol for a total of 110,210 per gallon vs the 114,000 in pure gasoline. So gas mileage will be about 3.3% worse with 10% ethanol.

That's why E85 is no bargain even if it's much cheaper than gasoline. Just doesn't have the btu's that gas has.


Some of the links I read they measured about 7% e from the fuel they tested but sold as up to 10%e.
In addition to btu count, e has a different burn speed (and cylinder pressure) that affect how much power is obtained from it that needs to be considered.

https://www.youtube.com/watch?v=ED_lf2-ut1A
https://www.sciencedirect.com/science/article/pii/S111006211530012X
https://www.6speedonline.com/forums/997-...l-analysis.html
 
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Originally Posted By: Miller88
Any modern vehicle will adjust timing based on increased octane. Unless you're direct injection or FI or some combination of the two, it's a small difference.

My parents' last escape (2.0T EB 2013) went from ~23 to ~27 going from 87 with ethanol to 91 ethanol free. Probably more of it was from using higher octane gas but the lack of ethanol probably played some part of it.


It's the other way around. Timing is retarded when the engine knocks. Otherwise timing is already ideal. If it's not retarded with 87, there's no mileage improvement. Lots of people think it, but there's lots of factors that affect gas mileage such as winter/summer gas, running the A/C during the summer, and of course the amount of idling/speeding varies by the tank. It's almost comical when people try to claim that running super vs regular improved by a certain small amount. My gas mileage can go from 16-21 just depending on the type of driving I did and the traffic at the time with the same gas.
 
Originally Posted By: Miller88
Any modern vehicle will adjust timing based on increased octane. Unless you're direct injection or FI or some combination of the two, it's a small difference.

My parents' last escape (2.0T EB 2013) went from ~23 to ~27 going from 87 with ethanol to 91 ethanol free. Probably more of it was from using higher octane gas but the lack of ethanol probably played some part of it.


Its not the octane that increased mileage, it is the ethanol that decreased it. It just happens that most ethanol free gas is premium fuel.
 
Depends what you call "modern" My late 90's Escort coupe would do it. One of the most common modification would be to disable the Knock sensor as it would see normal vibration as Knock, pull timing, which would create more vibration and put it in a loop. That's how it was from the factory. [censored] poor programming.

It would vibrate so hard the steering wheel would shake. If you pulled the knock sensor and put on a set of Ford Racing plug wires the idle would be so smooth that sometimes it almost felt like the car was off if you were at a stop. A CRAZY difference.
 
2012 Equinox 2.4. Daughter lives in OK. I time my fuel stop so I fill up in Miami Ok with E-Zero. I continue to keep E-Zero in the tank while I'm there. MPG goes up between 2.5/3.2 better MPG, and runs smoother to boot. E-10 stuff is crXX, and nothing more than Gov subsidized to the few who own ethanol plants. If it was so good???? Then why can't it stand on it's own merit???
 
Originally Posted By: oldhp
2012 Equinox 2.4. Daughter lives in OK. I time my fuel stop so I fill up in Miami Ok with E-Zero. I continue to keep E-Zero in the tank while I'm there. MPG goes up between 2.5/3.2 better MPG, and runs smoother to boot. E-10 stuff is crXX, and nothing more than Gov subsidized to the few who own ethanol plants. If it was so good???? Then why can't it stand on it's own merit???


What octane is the E-Zero fuel you're using in Miami, OK?

Although I never tried E-Zero fuel in my wife's 2001 Lexus RX300, which stated in the OM that 87 octane is acceptable and can be used regularly, and 91 or greater will get better performance. I However, I did try(over 14 years) all grades of fuel from 87-93 and I never saw or calculated any differences in MPG nor could I feel any performance differences. When I tested a grade of octane, I typically ran that octane the engine for 4-5 fill ups in order to get a baseline. I GOT NOTHING!
 
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I have noted little difference in fuel mileage based on octane changing and all else being held equal in my 2016 F150 with the 2.7. When I say that, that means 87, 89, and 91 octanes (even 93) all were E10 blends and delivered similar fuel mileage.

If I fill up with premium non-ethanol fuel, my mileage goes up around 4%.

From that, my take home is it is the ethanol content, not the octane, that drives the fuel economy difference.

I monitor the Octane Adjustment Ratio which is used in controlling the engine parameters. Remember, Ecoboost trucks recommend premium when towing heavy loads or for better performance. They are rated on 87 octane, but take advantage of higher octane fuels.

The trick when deciding to purchase Non-ethanol premium is whether it is cost effective to do so, and usually the price spread is high enough, you come out behind as the better fuel mileage isn't enough to offset the cost...
 
Originally Posted By: tmorris1
Originally Posted By: Miller88
Any modern vehicle will adjust timing based on increased octane. Unless you're direct injection or FI or some combination of the two, it's a small difference.

My parents' last escape (2.0T EB 2013) went from ~23 to ~27 going from 87 with ethanol to 91 ethanol free. Probably more of it was from using higher octane gas but the lack of ethanol probably played some part of it.


Its not the octane that increased mileage, it is the ethanol that decreased it. It just happens that most ethanol free gas is premium fuel.


They had an ecoboost engine, gas turbo direct injection - higher octane definitely increases mileage in such an engine.
 
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