Then you’ve collected data on the person’s car in the comment above where he claimed he got better fuel economy using E15?
Unless you have…
You keep using that word. I do not think it means what you think it means (theoretical).
Lower btu/gallon = lower mpgs is a fact. Stating that someone gets better mpgs with E15 is a claim inconsistent with basic facts. No ‘theory’ has been offered to explain it.
The following is the true gasoline octane ratings with various ethanol levels in ethanol blends. First, 87 octane 100% ethanol-free gasoline (E0) is octane 87. Duh!!
Second, inaccurate, but “designated” 87 octane 10% ethanol-blend (E10) has its gasoline component at 84 octane.
Third, inaccurate, but “designated” 88 octane 15% ethanol-blend (E15) has its gasoline component at 83.5 octane.
Fourth, inaccurate, but “designated” 87 octane 15% ethanol-blend(E15) has its gasoline component at 82.4 octane.
Only 87 octane E0 has its gasoline at 87 octane & has the best MPG, as prescibed by 87 octane gasoline engine engineers. No 87 octane ethanol-blend has any of its ethanol or gasoline components anywhere near 87 octane. In my five 87 octane gasoline engines, 87 octane E0 gains 8%, 8%, 7%- 8%, 7%, & 5% better MPG, over inaccurate, but “designated” 87 octane ethanol-blend E10.
Incorrect. 87 Octane means that the total octane value of what you’re pumping into your tank is 87 octane. Ethanol actually has an Octane value of 99.15. You get better gas mileage with E0 because burning a gallon of gasoline releases far more energy than a gallon of Ethanol. That’s why flex fuel vehicles running up to E85 get extremely poor gas mileage vs when they run E10 or E0
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I have no issues with E10 for modern cars and feel the tradeoff is OK. Fuel systems are sealed so it is harder for moisture to be drawn in to the alcohol.
The issue I have is with carbureted small engine equipment. I used to never have much of an issue with this. I used a fuel stabilizer or 2 cycle oil mix that had it already added. Then I started having problems. It was like I had to fight and fight if I left my stuff sitting more than a week, even with the stabilizer. Stuff I started daily was fine.
I talked to a small engine guy and he had two things. He sold me a new additive that is supposed to be better at stabilizing ethanol fuels. He also told me to go to a certain gas stations selling alcohol free premium and that I probably wouldn’t even need that. I am still using up the last of my old gas but will start refilling my cans with this stuff.
Nah. Ethanol has an octane of 114. The gasoline component to balance the ethanol octane, is 84 octane to make 87 octane E10. I am correct. Neither the ethanol or the gasoline is 87 octane. Just the average is 87 octane. You can derive the equation yourself, & use it to prove that only the average is 87 octane,.
The ‘average’ is 87, so the gallon of fuel is 87 octane. That’s all that matters, octane-wise. The E10 does have about 3% less energy, so mpgs will suffer a little.
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Of course not. The “ethanol in gasoline industry” tries to get America to believe 87 octane E0 & 87 octane E10 are the same thing. However, the btu difference between E0 & E10 is NOT the difference in MPG between E0 & E10. My last five low compression ratio 87 octane gasoline engines got 8%, 8%, 7%-8%, 7% & 5% better MPG with E0 over E10. Besides the btu difference, 87octane E10 has none of the ethanol or gasoline components at 87 octane, which 87 octane E0 does.
No it’s not:
scroll down to Ethanol (99.15 by the AKI or (R+M)/2 method, which is how the US and Canada determine Octane rating)
I haven’t seen any of that going on. That would be quite a feat if they were to manage it.
According to RFA:
Ethanol’s Blending Octane Number
Ethanol’s pure component octane number is 100 AKI. But its blending octane number is 109-119 AKI, depending on the octane of the finished fuel. Ethanol’s blending octane number is highest when used with lower-octane hydrocarbon blendstock.
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87 octane E10 gasoline blendstock is lower-octane 84, to which 114 octane ethanol is blended.
Since there were no posts in opposition to my post, I reiterate, that the “ethanol in gasoline industry” is trying to dilute our nation’s gasoline stocks even further. In the case of 88 octane E15, the gasoline blendstock is 83.5. If they succeed at forcing 88 octane E15 on the public, the “ethanol in gasoline industry” will try to foist off on the public, 87 octane E15. The gasoline blendstock for such, is 82.5… or a trace lower.
There is no direct relation between octane and MPG.
Ethanol has lower MPG because it has lower energy content.
Since ethanol contains oxygen it can be though of as partially “pre-burned”.
My biggest issue with ethanol has been in small engines. The stuff seems to gum them up if you let them sit more than a week. I asked my local small engine guy about this and he said I wasn’t the only one with this problem. He suggested I buy ethanol free premium. Only two stations in town have this so it is a little more effort but I get several cans at once.
He also sold me on some stabilizer which I do not think I will use until the equipment gets stored away for the winter. One of my riding mowers has a basically dead battery so it needs to start on the first crank or so, otherwise I am jumping it. It had been left sitting a month and fired right up like it had been running 5 minutes ago. It has been a night and day difference!
Apparently car engines are better able to handle this stuff, even when sitting. It think the sealed emissions systems to meet EPA standards help as moisture cannot get into the fuel system. The ethanol attracts moisture and many small engines do not have sealed systems as of yet.
As for my issues, I really think that someone who used small engine equipment on a daily basis would have no issues with ethanol. They would be running through it before it had any chance to attract moisture and gum up the carburetor.
Someone running a mowing service could probably use it daily until the end of the season and then use stabilizer and alcohol free to store it for extended periods.
I do OK with my mower on E10. I mow once or twice a week depending on how crazy the grass gets. But it’s a relatively new mower, so it hasn’t had time for cumulative effects yet. I do stabilize the tank during the winter, making sure to run the stabilized gas through the carb, and then I turn the fuel cutoff valve and let it run out of gas rather than shutting it down with the key.
My snowblower is more than 30 years old and it’s not faring quite as well. This may well be its last season. But that’s more because of parts that aren’t the engine that are wearing out (auger direction control, etc) and general rust than E10. It gets the same treatment in the spring that the mower gets in the summer, but it’ll sometimes go 3 or 4 weeks without being run if we’re having a mild winter. I’m not gonna pull that giant loud thing out for a 1/4" dusting when I can just swipe it off the driveway with a blade shovel. Still starts right up when I want it to.
I think some of the mowers that are having problems are the ones that have the bail lever on the handle that springs open if you aren’t holding it and kills the motor. Most people use them to turn the mower off rather than cutting off the fuel supply. They ground out the spark plug and use a brake to stop the engine rather than killing the fuel supply to the carb, so then gas sits in the carb and can gum up.
The only issue I had with E10 in a mower was that, after winter storage, the carburetor would always need rebuilt, whether I ran it dry, used fuel stabilizer, or neglected it. Nothing I did seemed to make a difference until I started using ethanol-free gas. I still stabilize my fuel when I buy it, and I still run the mower dry before storing it, but I haven’t had to rebuild the carb once since I switched to ethanol-free fuel.
I find this statement rather strange. It’s as if you’re saying, “Since I didn’t elicit any pushback, allow me to reiterate my opinion once again.” Why do you seem to be itching for an argument?
We’ve been hearing about this conspiracy theory, that E15 is going to be forced upon an unwilling public, for so long that it reminds me of The Boy Who Cried Wolf. If you’re that worried about it, the smart thing to do would be to choose a flex fuel vehicle the next time you buy a car.
Hmmm what could happen if you used the 15% Ethanol in a vehicle not designed for it? A few nasty things could occur. The actual fuel lines need to be able to withstand carrying that blend, so theres definitely that… Depending on what type of fuel injection Direct or Port injection is another factor. Direct injection would avoid the valves but port injection would include the intake valves, their seals and their seats…as well as the actual valve stem and head. So if those materials were never designed to see that sort of blend all sorts of nasty unpleasantness could befall the valve system. Who knows maybe even the Cat convertor needs to be specially equipped as well. But I know for sure the fuel lines, pump, and valve system should be the top areas of concern with using this blend.
Yes, the fuel pumps and valves damage was documented for port-injected engines.
Just for my entertainment, I happen to find a study of the early-2000 cars force-fed with E15 and substantial percent of them showed either one or both areas to be problematic, some down to pre-failure state, some to the actual failure.
Another thing is that as more and more ethanol is dumped into the fuel, the air/fuel ratio has to be properly adjusted, as otherwise you will get a nasty yellow “check engine” light since the ECM would not be able to keep the ratio properly for the downstream sensors to be happy.
I’ve recently read the research paper on that, where the experiment was to make vehicles not designed for E15 to swallow it and they measured the fuel trims as ECMs tried to cope with the change and how downstream sensors reacted to that.
I do not remember exact numbers, but all cars definitely observed shift in fuel trims, for something like quarter of them it went our of the range where ECM would still care to compensate for it and threw out a yellow CEL light.