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Non-Ethanol vs. Premium in 3.0 H6


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After my 95 Legacy wagon died with 383,000 miles a year ago, I was lucky enough to pick up a 95 Legacy sedan on Craigslist with only 141k miles for $1300. It needed some work, but it's a great commuter car. Now my wife's 95 legacy with 309,000 miles may be down for the count. I really like the 2.2, but I'd like to get something newer for her. I know the 2.2 stuck around for a few extra years in the Impreza, but I'd also rather get something bigger. I'm a bit scared of the 2.5, and there seem to be a decent number of 3.0 H6 Outbacks floating around.

 

My question is about "real" gas versus premium. I'm very lucky in that there are three gas stations in our little 20,000 person town that have non-ethanol 87. It's usually about 15 cents more per gallon, but the extra mileage makes it well worth it in my Legacy. It's also much cheaper than premium. My question is whether the lack of ethanol somehow offsets the extra octane of premium that the 3.0 calls for. We drive a lot - she'll put 20,000 miles a year on this, so the extra money for premium can add up to a couple of hundred bucks a year. 

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Unfortunately ethanol does not equate to octane. You will still need premium for the octane content. Though you may be able to get away with mid-grade if you don't drive with a lead foot.

 

Most of the premium grade fuel around here is ethanol free as far as I know. Part of why its $0.45 per gallon more than regular. (Here in C-ville at least)

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whether it has ethanol in it or not, run the higher octane rating fuel in the H6. Lower octane will lead to a little knock, that will cause the ECU to retard the timing. Some say, the car also gets more/faster carbon buidlup in the cylinders with regular gas.

 

You could try the mid-grade in winter and run the hi-octane in summer. I run high octane year round.

Edited by 1 Lucky Texan
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Ethanol has a HIGHER octane rating than gasoline, that's why the turbo guys love to run E85.  With 85% ethanol it's 105 octane.  It has significantly less energy content as mentioned above, this is why it gets worse mileage.

 

But the octane rating is what your H6 engine cares about.  So a 91 octane with 15% ethanol will have the same detonation resistance as 91 octane with no ethanol.  Running ethanol in a vehicle made before 2001 is asking for trouble, however, as the rubber components were not designed to work with ethanol.

 

I run 91 octane year round in my 3.0 H6.

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I'm kind of surprised there was actually a difference in mileage. My '96 Outback burned ethanol and non-ethanol exactly the same. Had the EJ22 in it too. How much of a difference are you seeing?

It was a couple of years ago that I ran the numbers, but I want to say it was a pretty consistent 2 mpg better with the real gas. I was keeping pretty detailed records at that time. I'd say I drive about 95% on the highway, so it's relatively easy for me to see how variables affect things - i.e. cruising faster or slower, real vs. ethanol. 

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Many people get similar results as you have noticed, they just usually are not that high. I have run 87 pure gas in my Brat and 06 Ford Ranger for the past 3 years are more. Best I can remember is about 3% increase in mileage which equates to the stated 3% energy increase. We have a 93 premium no ethanol source in a neighboring city. Filled my wife's XT there and convinced her to fill there next time. She claimed that to be the highest local mpg she has seen in her XT. It has the mpg display. But for convenience's sake she will not stop by there at all, it is about 3 miles out of her way to and from work and it does cost about .50 more a gallon. Sure enough alcohol has a high octane rating but 93 is 93 and 87 is 87 regardless. The fuel without alcohol is better in my opinion and I don't mind paying extra for it as it seems you pretty much feel the same way. My Brat was having all sorts of trouble several years ago in a cold snap that I believe was caused by ethanol. The 87 runs me maybe .15-.20 more a gallon. Cheap in my opinion! 

 

You can try searching Pure-gas.org. They list nonethanol stations by state and city. List 272 stations for Va. bet there is more not listed. Forgot the little hyphen!

Edited by bratman2
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Ethanol isn't all that. One problem is that it will also carry every drop of water it comes in contact with thru the injection system, second, it has a 90 day life and then becomes acidic, which starts deteriorating the fuel system causing no starts, etc. 

 

We've been running state mandated gasahol for years here, and one affect has been to run all the small engine vendors out of business. They get stuck for the warranty service for units the big box sells. Now the remaining ones require no alcohol premium and their fuel additive for warranty purposes - which works. 

 

i work auto parts, I get a lot of folks who come in with driveability issues, or trying to revive a car that has sat for awhile. I can sell a lot of fuel additive, and do, but my first recommendation is to use a tank of no alcohol premium first to see if that doesn't clear up the problem. If it's been sitting, drain it and refill with no alcohol premium. No news is good news, hopefully they got it fixed. I never hear back they have continuing problems. 

 

I have tried tankfuls of gasahol and no alcohol fuel back to back, and, anecdotally, saw a 2MPG difference, plus more power. To do that requires using a grade with more octance, but the result is less retardation due to knock. That makes more power, and if you are really driving the same, you use less pedal. You do the math to see if it's justified for you, basically, I decided to just say no to the cheap gasahol at the pump. It's less octane than the '60's and not saving all that much if the car is running better. 

 

You get what you pay for. 

 

Missouri is now floating legislation to eliminate the mandate on blending alcohol. One aspect is that the refiners have purchased feed corn stock to make it, driving the price up, which translates to more expensive beef. Another is the deterioration issue. The opposition camp sounds very environmental, but the bottom line is that the agricultural lobby is dead set against ending their monopoly and government subsidized handouts. And that goes to the fact they think gasahol couldn't survive on the open market. It has to be forced on the consumer with that perspective. Which is not the kind of country I thought I would grow up to live in. 

 

Give me free choice and just see what would happen. Texas and Oklahoma aren't mandating gasahol, guess what, you can't find it. It won't sell enough to bother putting in a pump. 

Edited by tirod
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Many people get similar results as you have noticed, they just usually are not that high. I have run 87 pure gas in my Brat and 06 Ford Ranger for the past 3 years are more. Best I can remember is about 3% increase in mileage which equates to the stated 3% energy increase. We have a 93 premium no ethanol source in a neighboring city. Filled my wife's XT there and convinced her to fill there next time. She claimed that to be the highest local mpg she has seen in her XT. It has the mpg display. But for convenience's sake she will not stop by there at all, it is about 3 miles out of her way to and from work and it does cost about .50 more a gallon. Sure enough alcohol has a high octane rating but 93 is 93 and 87 is 87 regardless. The fuel without alcohol is better in my opinion and I don't mind paying extra for it as it seems you pretty much feel the same way. My Brat was having all sorts of trouble several years ago in a cold snap that I believe was caused by ethanol. The 87 runs me maybe .15-.20 more a gallon. Cheap in my opinion! 

 

You can try searching Pure-gas.org. They list nonethanol stations by state and city. List 272 stations for Va. bet there is more not listed. Forgot the little hyphen!

 

Great site - I have the app on my phone. 

 

Ditto to what someone else said about small engines. I heard about the problems a couple of years ago and now I'm anal about only getting real gas for the mower, trimmer and snowblower. 

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My question is about "real" gas versus premium.

 

in my experience it doesn't matter.  i run 87 with ethanol gas (that's all you can get where i live) in all of mine, it's not a big deal.  premium is suggested, not required on the H6's.  probably depends on year - but mine are 02 and 03.   212,000 miles and 175,000 miles.

 

i've run mine (multiple different vehicles) with premium and non-ethanol blends when traveling and noticed zero difference and i calculate gas mileage at every fill up.  but i also live in the mountains and travel loaded a lot - with a full family/people.

 

your gas bill may take a hit simply due to size of vehicle, weight, and an engine that already gets less gas mileage to begin with.

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"To do that requires using a grade with more octance, but the result is less retardation due to knock."

 

That isn't quite true. Octane is octane regardless of ethanol or not. Many variables can effect fuel such as age (ethanol fuel more susceptible), contamination, percent below or above grad, and additives. One of my neighbors years ago was a state fuel inspector. When fuel is checked randomly for grade it can be a certain percent below or above and still pass.  My 87 nonethanol comes from a fuel distributor that also is a large commercial, agriculture and mining equipment tire company. I have been a customer of theirs for almost 34 years. Between these two I have learned a lot about fuel. Also the ethanol Federal subsidies have been dropped sometime ago unless it has been reinstated.

 

Slightly off topic I also own a Moto Guzzi which has a nonmetal fuel tank and requires premium. Alcohol in fuels in the US have caused issues with these and several other brands from Europe. Mainly fuel tank swelling and blistering of the paint job. Nothing like pulling your tank to service a bike and cannot get it back in for the love of Christ! I will pass on the alcohol on all my vehicles if given the choice.

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