Just got back from south florida and went to buy gas. Every station no matter what brand has a mix of less than 10% alcohol blended in. I always get 26-28 mpg with my santa fe 3.3 (same engine as in the sonata). This wonderful gas which cost the same as the gas back home got me 22mpg. After leaving south florida filled up with real gas and watched the milage jump back up to 27.3 for the trip home. So be ware if you don't get the posted mileage make sure you are not pumping a gasoline blend. The engine ran fine just burnt more gas.

I use shell all the time which has ethanol blended in - are you saying that the car will get better mileage on 100% gasoline ?? holy crap - I will have to try that next time ..

Are you saying Alcohol or Gasahol (Ethanol)

http://en.wikipedia.org/wiki/E10_fuel

Confirms what many of us up in the north have already known for many years. Regular ethanol blend = less mpg, Regular gas without ethanol = more mpg.! Some newer vehicle adjust better and can avarege nearly the same mpg with either.

Lower mileage yet higher Octane. Might even prove that Premium is a waste

after all! :trophy: Of course my Engine runs like Krap :w00t:

Ethanol contains less power. (It is a slow burning alcohol.) According to Wiki, the energy density for ethanol is 23.5 megajoules per liter compared to 34.8 MJ/L for gasoline. (Gasoline has 48% more energy.) A 10% ethanol blend has an energy density of 33.7 MJ/L and contains only 97% as much energy as 100% gasoline, which causes both power and mileage to drop.

E 85 is 105 Octane. According to the Ethanol Industry and a different Wiki page,

an Ethanol blend produces higher octane. I don't know how that translates into

power though?

*OK Wiki says more Octane equals more Power!

http://en.wikipedia.org/wiki/Octane_rating

This post has been edited by MiamiLX: Jun 11 2008, 01:11 PM

Exactly,

For years I did a lot of tuning with ethanol. In the real world your #s are about spot on. For every 10% addition of ethanol, your real world mileage should drop 3%.

Our testing over a 20 year period has shown this to be very close. Usually it'll come out a bit more like 4%, on average.

I’m not an expert in this area, but…..

Octane describes a fuel’s resistance to pre-detonation. That’s all. Generally that means it burns slowly. To make premium fuel, somewhere in the process, they add “additives” to make it burn slower. The energy density remains about the same. Premium and regular fuel have the same power (99.9%). Regular fuel just burns faster and can ping more easily.

However alcohol is different than gasoline. When it burns, it doesn’t release as much power. Alcohol naturally burns slower and when combined with it’s flash point, is very resistant to pre-detonation. That’s why E85 has a 105 octane rating.

I thought they add 10% Ethanol everywhere in US. Where i can get 100% gas?

Great Falls, MT :thumbsup: See ya soon! :grin:

I could definitely be wrong, but I didn’t read that when I read the Wiki text. I did read that higher octane fuel had a higher activation energy.

“Higher octane ratings correlate to higher activation energies. Activation energy is the amount of energy necessary to start a chemical reaction. Since higher octane fuels have higher activation energies, it is less likely that a given compression will cause knocking.”

But I’m still 99% sure that higher octane does mean more power. The only line I found in that Wiki text that dicusssed octane and power was, “It should be noted that octane rating does not relate to the energy content of the fuel.”

If you're hitting Great Falls, just remember that there are a lot of cowboys there, who only wear chaps with the cheek parts cut out!!!!! So, you see a lot of Mr. Harry Bum there.

I think they're close to Brokeback, as well..............

This post has been edited by Tommer: Jun 11 2008, 02:02 PM

......says the fella from Cranbrook, BC... (where?)

:grin:

Craigslist.org :innocent: :P

Higher octane enables a high compression engine to make more power without detonating. However, there is not more energy in higher octane gasoline.

Instead of equating octane with power and mileage, use energy density as blue07 posted. Diesel is even higher than gasoline, thus the outstanding mileage.

Esso here has no ethanol to my knowledge, but Shell advertises the 10% ethanol to the lowest grade fuel - I would think your Esso - err Exxon would be the same ?