MPG with gas-ethanol blend vs pure gasoline

Has anyone checked gas mileage (MPG) in the identical vehicle using an ethanol blended gasoline in one fill-up, and then pure (non-ethanol) gas in other fill-ups? All the gas pumps in my state have an ethanol
blend, so I don't have a chance to compare with pure gasoline. I've had people tell me that pure gas delivers measurably better MPG ... better by 10% or more. Has anyone checked one gas against the other in the same car? Results? MrBear
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Wed, 21 Nov 2007 14:17:43 -0600, snipped-for-privacy@webtv.net (Mister Bear) wrote:

In a word, no. But the debate/discussion has lots of inputs. Simply Google: ethanol mpg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Mister Bear wrote:

Ethanol has about 30% less energy in it than the same volume of gasoline. So 10% ethanol gasoline should have about 3% less energy than regular gasoline. And you should get about 3% less gas mileage.
Jeff
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Esso in the province of Ontario started using ethanol last summer. Prior to that they used MTBE, which is also an oxygenate. Before that it was MMT, which is not an oxygenate.
With my very detailed recored keeping, I noticed a couple of percentage point decrease in mileage when they switched from MMT to MTBE, but no change going from MTBE to ethanol.
--
Tegger

The Unofficial Honda/Acura FAQ
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Gas has a higher btu rating than ethanol. You will get better milage out of 100% gas. Ive never really bothered to check the difference. When I had a 35-40mpg vehicle driving 15-20000 mile a year gas was cheap ($.80) so didnt care. Now I dont drive much 5000miles on a bouht new 2005Pilot. If two stations side by side one blended, one 100% I would go with the non-ethenol blend 100% gas.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@webtv.net (QUAKEnSHAKE) wrote in

No fuel is "100% gas". A goodly proportion is made up of detergents and other additives. Then you have the octane boosters.
In the old days you had tetra-ethyl lead added as an octane booster. Later it was replaced by MMT. Neither of these had a significant impact on fuel mileage.
What *did* finally adversely affect mileage was the addition of oxygen to the fuel. Oxygen was added through the use of MTBE or ethanol, the resulting fuel mix being known as "reformulated gasoline".
If you want to maximize fuel economy, you have to remove the oxygen by going back to non oxygen-containing additives. Which ain't gonna happen.

I did, and it isn't much. Perhaps 2%. Until you do whole-year studies with the same car, the same fuel brand and the same octane rating, it's impossible to pick out changes that are not due to simple randomness.

You can find ethanol-free gas almost everywhere. It's usually in the form of the the "premium" octane grades, like 91 pump octane. The lower the octane, the higher the ethanol content. But you won't find non-oxygenated anywhere in North America now that MMT is out of use.
--
Tegger

The Unofficial Honda/Acura FAQ
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Tegger wrote:

You have that one backwards Tegger. Ethanol has a naturally high octane variously reported at somewhere from 113 to 129 and is used in fuels in part to increase the final octane rating.
http://www.gov.mb.ca/est/energy/ethanol/ethanolfaq.html
http://en.wikipedia.org/wiki/Octane_rating
In many cases premium fuels actually have a higher ethanol content than their regular fuel counterparts because adding ethanol is one of the simple ways to increase octane ratings.
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I filled up today at a local Shell.
On the pump was a sticker. It said: "87 octane: contains up to 10% ethanol 89 octane: contains up to 5% ethanol 91 octane: contains no ethanol."
Want me to take a picture and post it?
--
Tegger


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Tegger wrote:

The difference in energy content between E10 (10% ethanol) and E0 (no ethanol) gasoline is about 3%. At about $3.00 per gallon, that works out to $0.09. Not enough to make using higher octane worthwhile.
Jeff
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Tegger wrote:

Post whatever you like, but the fact is that ethanol is a higher octane fuel than standard "gasoline" and is commonly used as an octane booster. I have no idea where you live or what the situation is with your Shell station.
Have a look at the reference articles I posted or the dozens more which are readily available.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload


But ethanol is not used as a fuel in road cars, only as an additive in gasoline fuel. The Manitoba document you cite explicitly says you could not practically use ethanol as a fuel in road-going cars.
Ethanol may be a high-octane additive, but it's a particularly poor choice as a gasoline octane booster. Ethanol was a non-starter (ha ha) before the government started hiding its real cost by taking money from your left pocket so they could put it in your right, and then by mandating the use of ethanol.

Ontario, Canada.

All the Shells in my province have that sticker, from what I've seen.
The Esso stations in my province all have stickers that say the gas "may contain up to 10% ethanol". But then I checked the MSDS's for Esso's unleaded gasoline. No ethanol at all, just MTBE (up to 15%).
Those pump stickers may be a legal labeling requirement rather than a reflection of what's actually in the gas.
Shell's MSDS's do not even list the octane booster. They say only that gasoline makes up ">90%" of the fuel mix. Shell is probably taking advantage of the "proprietary" exemption from revealing its oxygenate in the MSDS's.

I just did. The Manitoba government article is your typical ethanol-loony propaganda bumpf. Manitoba farmers are reaping a substantial financial harvest from the ethanol mandates, at the expense of taxpayers across the country.
However, that article did contain this nugget: "In order to produce Regular Unleaded gasoline with ethanol, a blender must have access to an 84.5 octane (or "sub-octane") grade of petro-gas. In some markets sub octane gasoline is not made available to blenders. In these locations, Regular Unleaded (the lowest price grade gasoline with the highest sales volume) does not contain ethanol. In markets where sub octane gasoline is available, however, ethanol blended Regular is usually less costly than petro-gas Regular."
I think the answer here may be that in my area they may be using sub- octane to make Regular. Then they're relying on the heavy tax subsidies that accompany ethanol to be able to offer heavily ethanolized Regular.
Grades above Regular may use better base stocks which do not require so much ethanol to make them usable, but then the seller can't claim those subsidies, so has to charge more.
And if our 91-octane uses MTBE instead of ethanol, there are no subsidies at all.
--
Tegger

The Unofficial Honda/Acura FAQ
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
From:

Explain E85. Is using 85% Ethanol still considered an additive?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@webtv.net (QUAKEnSHAKE) wrote in (Tegger)

I forgot about that. In that case the alcohol *is* being used as a fuel.
--
Tegger

The Unofficial Honda/Acura FAQ
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
An examble 2008 Chrysler Sebring mileage ratings 19/27 with gas 14/20 with E85 (85% ethanol) This site shows http://www.fueleconomy.gov/feg/noframes/24007.shtml
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 26 Nov 2007 10:51:13 -0600, snipped-for-privacy@webtv.net (QUAKEnSHAKE) wrote:

Check out the flex fuel vehicles:
http://www.fueleconomy.gov/feg/byfuel/FFV2008.shtml
notice how they are almost all trucks? The reason is that they get a big credit on their CAFE when they sell a flex-fuel vehicle. So, while you may think that your GMC Yukon only gets 15 mpg, GM gets a credit for building a 33 mpg truck. No shit. Of course few of these trucks will ever see E85. But the phony fuel economy rating allows GM to sell more Suburbans, Hummers and Yukons. In this very real way, E85 is helping to squander fuel and trash the environment.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Related Threads

    Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.