ETHANOL FREE fuel = 16% increase in mileage....

[KrautBurner]

well,
I'm not sure if this counts as a "Success Story" or if it belongs in the "Unicorn's Corral"

I've got a 1991 Geo Metro 3/5 with about 185,000
I just picked it up a couple months ago
I drive 55-60 miles each way to work (90% 2 lane highway 55/60mph (normally doing the speed limit to 5 over) lots of long hills)

I logged the first few tanks averaging about 44mpg (best of 46mpg)
then switched to NON-ETHANOL Regular (87oct)
the first tank (was actually only about 2/3 of a tank) got me about 49.5mpg and the 2nd tank got me 51.1mpg
this is a much larger difference than I was expecting

I just filled it up for the 3rd time, I'll log it,
then go back to regular E-10 for 2 or 3 tanks to see if it drops back down

what do you guys think?
My Metro (Geo Metro) | Fuelly


Edit,
the first few tanks were with the windows down about half the time
ever since the 3rd or 4th fillup, I've been keeping the windows closed or cracked open about an inch (not sure how much that makes a difference)

[KrautBurner]

I realize my testing is still in it's infancy

but I am not "trying" for a personal best, these are "real world" numbers for my commuter (I fill up about every 300-350 miles (as I dont trust my fuel gauge yet) and it's another 110-130 miles before I'm back to my home fuel station)

I've got a friend who is convinced that I am "manipulating" the numbers somehow (driving different with the E-0 fuel) but I dont think I am
I spend most of my commute staring at the tail lights of the car infront of me most of my commute, going about or a little over the posted speed limit
I do use the "Georgia Overdrive" whenever possible, but I've done this in all my manual transmission vehicles for years

[mpg_numbers_guy]

If you don't mind saying, what are you paying for ethanol-free gas versus regular unleaded? I've thought about trying a tank in the Insight, but I've read that on my car there really isn't much of an improvement. Are there many stations selling ethanol-free fuel in your area?

[me and my metro]

I have found that E10 costs you about 10% fuel mileage. I can only get clear Premium in Oregon so only the small engines get that. E10 premium is $3.40 and clear premium is around $4.00.

[KrautBurner]

this is an Independent fuel station, i'm not sure what brand fuel they sell

$3.799 / Gal for Ethanol Free
$3.399 / Gal for E-10 at the same place
$3.199 / Gal for E-10 at Costco (where I normally fill up)

they also have ETHANOL FREE Premium at that station
there is another station in town that sells E-FREE Premium as well (about the same price

[KrautBurner]

if anyone is looking for Ethanol Free fuel

https://www.pure-gas.org/

[Frank Lee]

Nah, I'm usually looking for a good price on E85.

[Stubby79]

I've gotten farther on each tank in my Echo since switching to premium, which afaik is ethanol free at that station.

It also coincides with warmer weather, mind you...but even last summer I wasn't getting 600+ km/tank like I am now. We'll see in the fall if it's purely the warmer weather.

[19bonestock88]

Makes sense, ethanol free fuel is more energy dense than ethanol fuel

[2000mc]

While e0 is more energy dense than ethanol, I think the difference between e0 and e10 should be about 3%
In a study looking at mileage with different ethanol blends the general trend follows the energy density. That being said, your mileage will vary, The Ford Fusion tested did almost 15% better on e0 vs e10, while a flex fuel impala did just over 15% better on e20 vs e0.
http://www.speedperf6rmanc3.com/cont...evel_Study.pdf