E10 vs std 87 oct RESULTS ARE IN

bhuff30

Founding Member
Dec 11, 2001
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Olathe KS
Over the last 2 weeks, I've been doing a test, to see if there is actaully a difference in milage (as reported by some) when using 87 octane vs E10 (10% ethanol, 90 oct). The test was done by running the E10 first, with similar driving styles, milage and conditions (never used the AC). The first tank, being on E10 netted me 22.8mpg. The second tank, on streight 87 oct netted me 22.9mpg.
Just thought I would share incase anyone was interested. :stick:
 
I didn't notice anything difference seat of the pants. I've only run at the drag strip once in this car, and that was the night I ran the 14.675 @ 94mph in my sig. In fact, I was running the 90 oct that night, and for a bone stock car that is an excellent time. I'd say there is no difference in power.

I used to have a pinging problem, and it was always better when I ran the 90 oct E10. However, if E10 sits for very long, you can certainly have some problems. The alchole will evaporate first, lowering the octane content. Also, my understanding is that alchole can hold water, but I don't think it is a problem in E10?

AHHH, fun dispelling stangnet myths. :D
mogs01gt said:
what about power?

RoadconeTuning said:
when i run e10 i notice a drop in power, and that it is more prone to detenation. but thats my personal experience
 
Twisted said:
E10 has less power than straight gas.

Wait until the E85 craze hits.


Ummm..... you mean the energy content is lower than regular gasoline?

The energy content of E10 is only slightly lower than that of gasoline since there is only 10% ethanol. As for E85, I love the stuff. The corrosiveness and other bad qualities of pure ethanol are much better with the 15% gasoline, and the octane rating is over 100. With higher octane, you can run more compression, which increases fuel econmy.
There is a lot to be said about ethanol. Brazil is using 100% ethanol for their automobiles. Ethanol is reneuable and can be made from corn, sugar cane or even beats. The carbon released during the burning of ethanol origionally came from the atmosphere because the plant takes in CO2 to grown. Seems pretty good to me.

In fact, I want to convert the 88 to run on E85. With 100 octane and being oxygenated seems awsome to me. I've read that short term use of E85 will have little effect on the fuel system because the 15% gas makes it so much less corrosive. My only hold back is that the nearest E85 station is still 30 miles away, actaully one 30 miles to me west, and one 35 miles to me east.
 
great thread! everyone needs to post their experiances with this new gass as it will effect all of us trying to mod our cars and probably those of us who are not modding as well.
 
bhuff30 said:
As for E85, I love the stuff. The corrosiveness and other bad qualities of pure ethanol are much better with the 15% gasoline, and the octane rating is over 100. With higher octane, you can run more compression, which increases fuel econmy.

I don't know about it increasing fuel economy. Even though the octane rating is higher, the stoich and max power ratings are considerably richer, meaning you have to run MORE fuel, which would negate any economy increased by the higher compression ratio. But as the price of gas continues to rise, it may still be cheaper the run the e85.

======== stoichmetric AFR ===== max power rich AFR
Gasoline ---------- 14.7:1 -------------------12.5
100% E-85 ------- 9.73-9.8:1 ------------- ~ 9:1 - 8:1
100% fuel ethanol - 9:1 ------------------- ~ 7.2:1
 
I've run the test twice with my g/f's Hyundai. Both types using 87octane fuel, the E10 was about 6-7% lower in mileage. I don't remember the specific numbers for mpg.

Not that it's relevant in this forum, but it's noteworthy.
 
bhuff30 said:
The energy content of E10 is only slightly lower than that of gasoline since there is only 10% ethanol. As for E85, I love the stuff. The corrosiveness and other bad qualities of pure ethanol are much better with the 15% gasoline, and the octane rating is over 100. With higher octane, you can run more compression, which increases fuel econmy.


You should read the department of Energy study on flex fuel vehicles and the differences in mileage E10 and E85. Most of the vehicles had around a 28% decrease in mileage when using E85.

http://www.nrel.gov/docs/fy03osti/33058.pdf

"In fuel economy testing, the E85 vehicles achieved fewer miles
per gallon (mpg) than their gasoline-fueled counterparts. The
Caravan got 16.4 mpg in combined city and highway driving,
compared to 22.5 mpg for an otherwise-identical Caravan
fueled by gasoline. Testing of the Taurus produced comparable
differences between the two fuels. The Fuel Economy
Guides for 2002 and 2003, published jointly by DOE and EPA,
support similar fuel economy expectations for most FFVs."
 
you noticed a small drop because your engine is tuned for regular. it is running lean because of the oxygen content of c6h12o6. 2.5 - 5 percent leaner.
if you are typical stock and you are running 14:1 you changed to 14.7:1. if by some chance you are leaner than 14:1 you moved into a blow torch zone.

i'm not an alarmist, but before tearing it up, fix the tune. the combination of lean and the increased temps on sharp edges in your combustion chamber and advanced spark can lead to probs. as for me, i AM on the edge with this tune, and it would no doubt blow me up. it's just a matter of time. i had to fatten it up to calm it down with 93. add 5% lean and i go back to the danger zone.
 
Please note, I wasn't implying that you'll get better fuel ecomony with E85. I was stating that increasing the compression will help recover some of the fuel economy lost when you run E85.

No need for Flame throwers. hehe :flame:


bhuff30 said:
Ummm..... you mean the energy content is lower than regular gasoline?

The energy content of E10 is only slightly lower than that of gasoline since there is only 10% ethanol. As for E85, I love the stuff. The corrosiveness and other bad qualities of pure ethanol are much better with the 15% gasoline, and the octane rating is over 100. With higher octane, you can run more compression, which increases fuel econmy.
There is a lot to be said about ethanol. Brazil is using 100% ethanol for their automobiles. Ethanol is reneuable and can be made from corn, sugar cane or even beats. The carbon released during the burning of ethanol origionally came from the atmosphere because the plant takes in CO2 to grown. Seems pretty good to me.

In fact, I want to convert the 88 to run on E85. With 100 octane and being oxygenated seems awsome to me. I've read that short term use of E85 will have little effect on the fuel system because the 15% gas makes it so much less corrosive. My only hold back is that the nearest E85 station is still 30 miles away, actaully one 30 miles to me west, and one 35 miles to me east.
 
Yes, E85 has a higher octane, but you need to use ~33% more E85 than with a straight gas car. Another way to say it is 1 gallon of gas has the same energy content or power as 1.33 gallons of E85.

I agree that it is great to use corn and reduce our dependency on foreign oil, but just keep in mind that you need to use more of it.
 
88ssp said:
How do you know what you are getting? Regular 87 vs E10?

You can look here to see if your area is under the federal mandate for the addition of 10% ethanol to your fuel.

http://www.epa.gov/otaq/rfg/whereyoulive.htm

If you're in an area that is not under the mandate, you still may be receiving E10. All pumps must be marked "Contains 10% Ethanol" or similar if they are dispensing this reformulation. Usually it's on the front of the pump or on the inside profile. It's normally easy to find.