Ethanol Free Fuel & Better MPG
 

Would the fuel economy on my Civic VX improve if I were to use ethanol free gasoline? Just recently, I'd discovered a gas station which sells 87 octane of unformulated gasoline that's close to my home. I'm curious to find out if I could even come close to the original EPA gas mileage estimate of 47city & 56 Highway.

I heard ethanol free gives like 15% more mpg. Not sure though.

It depends on the vehicle.

In the bug, it gets up to 3mpg better with midgrade gas and I know of no source of ethanol free gas other than RUG. So for that one ethanol free does not get the bug better milage.

When we had a 4.6L 2000ym Lincoln town car there was up to a 2 MPG difference on ethanol free, so it wasn't worth the higher price of the ethanol free.

The 2008 3.3L Hyundai sonata gets 3 to 4 mpg better on ethanol free so for that car it is worth it when we can get eFree.

Bottom line, test it.

I ran a full tank of ethanol free gas in the Black Widow back in the day, and it had absolutely no affect on mpg, I just ended up paying about 8 dollars more for the fill-up.

Here's my Fuelly log of the tank back in 2012:

19 1/22/13 402.00 9.00 44.67 3.359 75%
18 1/8/13 400.00 9.00 44.44 3 .329 75%
17 12/23/12 398.00 9.00 44.22 3.179 75%
16 12/7/12 395.00 8.86 44.59 3.899 75%
Tried "no ethanol" gas to see if it would make a difference. Found out it only costs more, didn't make any difference in gas mileage.
15 11/23/12 417.00 9.39 44.41 3.259 75%
oil change with synthetic & premium filter = 40.00
14 11/12/12 430.00 9.62 44.69 3.299 75%

Doing the math, it would need to give you over 20% better mileage to be cost effective, unless it has other hidden benefits, like longer engine life, or suddenly turning your crappy econobox into a chick magnet . . . .

+1 on the depends part. Gas itself varies from station to station. I can see a 5 mpg difference in buying gas from sheets vs shell or bp. All claim 10% ethanol. Now going with 89 or 93 with the 2 gen insight you see a boost in mpg and performance, but its not cost effective.

Now mixing 4 gallons e85 with regular you see both a performance increase, about a 5mpg boost and an instant savings as e85 is like 25 cents cheaper a gallon.

I agree with the others, it depends. I've measured little to no difference with pure gas vs E10 in my vehicles.

Save your money, not worth the extra cost for auto engines IMO.

OTOH, wish we did had a station closer to here. I WOULD spend the extra money for non-ethanol gas in our lawn equipment if the closest station wasn't 50 miles away.

Usually the extra mgp isn't worth the extra money. When I got the cobalt 2 years ago I used E0 to try for big numbers, 2 years ago same time of year 44.99 3-tank, last 3 tank on E10 was 43.7. I think the is pretty close to normal. I think there is a 3% energy content difference so it would be normal to expect that difference.

According to the EPA fuel economy page:

Do EPA fuel economy estimates account for the use of ethanol blends that are common today?

No. The EPA fuel economy tests use 100 percent gasoline, and no adjustments are made to account for ethanol. Most conventional vehicles using E10 (10 percent ethanol) will experience a 3 to 4 percent reduction in fuel economy.

Also they list the difference for some e85 cars in the e85 -vs- e0 for example a 2012 Impala is 13/16/22mpg on e85 and 18/22/30mpg on pure.

I would say the 2012 Impala is programmed to take advantage as much as possible on the e85, that year uses the new high compression, direct injected, variable cam phasing, 3.6 that makes 300 hp. Michigan state police vehicle testing that year ran both e10 and e85 during the testing and the Impala (as well as other e85 cars) ran quicker and faster with the e85. The Impala ran a 15.81 sec 1/4 mile at 91.5 mph on regular and a 15.53@93.45 on e85. Top speed went from 149 mph to 150 with the e85.

I understand how e85s cooling properties and high octane can make more power but with 33% less energy the e0 I don't see how it will ever improve economy even if you specifically designed a engine to use only e85.

e85 is a double edge sword. Some intelligent cars will sense the extra oxygen in the exhaust and go richer, which means more power and you burn more fuel than gas alone. Other cars that constantly adjust timing and vvt based on load will allow more timing and adjust the valves for MORE POWER but run lean.

Now you can buy e85 gizmos that piggy back the injection system and if you need to remove the head for any reason get it milled to a 13 or so to 1 compression so you can run e85 24x7.

Running more boost with e85 is tricky as the engine maybe be able to handle more boost vs more cr.