There is a station in my area (Fasttrac) that has a 91 octane gas, with no ethanol. I have filled up with this the last two times. Can't say I notice a significant difference, but I have not established any type of baseline testing for mileage or power.

Anyone have any experience with no ethanol gas?

 

Wonder what octane booster they use instead?

 

You've probably been switching back and forth without knowing it over the years. Ethanol gas (E10) is nothing new, many areas of N. America have had it for 20-30 years. It's only recently that retailers were forced to advertise the presence of ethanol. Don't believe the myths that you might read about it.

 

My father owns a gas station here in PA, and he said that all gasoline (under law) must now have 10% ethanol here in PA. Gas mileage with the Ethanol blend will be slightly decreased (3-4%)...so rather than 22MPG, you'll get between 21.12 and 21.34 miles per gallon...

I use 93 Octane Ethanol Blend and do pretty well on mileage. Recent 120 mile highway trip cruising at 68-72 got me 28MPG.

 

Your figures are dead on, I average around 18 to 19 MPG at around 72 with the SC model. I have gotton to 21 on the highway with the use of some Octane boost and a light foot with low wind and good tempratures.

 

Yup, spot on info. Certainly flies in the face of all the myths!

 

Is ethanol an octane booster? I thought it was more of a filler, cheaper than gasoline, and supposedly was introduced to reduce our need for foreign oil?

If so, I should get better gas mileage and performance from non-ethanol gas?

 

Other than Jagular, not sure if it was understood, I am filling with NON-ethanol gas.

 

Yeah, Ethanol is a filler...cheaper than gasoline and they've found that 10% really won't effect the performance of gasoline too significantly. If I could get "100% gasoline gasoline" here, I would. But EVERYTHING has 10% Ethanol.

It's also cleaner energy, so you're more likely to see these regulations in liberal-controlled states. That said, PA has a strong conservative government, so I don't know why they enacted this legislation recently.

To answer your question, though, the best gas mileage and performance will come from non-ethanol gasoline that you are currently using. I got that out of your original post.

 

Pure ethanol has higher octane rating than basic gasoline, so it's easier and more convenient for refiners to use it to obtain the desired rating. It is NOT cheaper than the equivalent amount of gas which is where the politics come into play. There's lots of info on the web that goes into the background on this.

As noted above, the difference is about 3-4% in energy content, most drivers note no difference in practical, real world terms.

 

Thanks for the detailed reply. Staying with the non-ethanol sounds like the best way to go.

 

If you can get your hands on it, and it isn't much more than the blend, by all means, go for it. You'd be foolish not to.

 

Yes, but what is used to boost the octane? Ethanol has some detergent properties as well. The lower energy content of ethanol means you are cheated if you pay the same for ethanol spiked gas as for the old fashioned stuff. Ethanol has oxygen in it as well as lower energy chemical bonds, which is where the energy comes fom during combustion. The oxygen content delivers less energy per unit mass than carbon bonds: valence is two for O2 and four for Carbon, per atom. Oxygen weighs a bit more ( mass actually, but weight is more commonly used to refer to mass, colloquially) but produces less energy when the bonds are broken and re-connected.

 

This should partially answer your question

A Primer on Gasoline Blending « EPRINC

 

There is also high elevation formulation as air pressure is lower so vapour pressure has to be also.

Basically, all California gasoline is 5% ethanol or higher. Other locales may use other octane improvers. I am not aware of ny "naturally" blended high octane gasoline sold retail, that is gasoline reformulatef with higher octane fuel ( other than ethnol) and not chemical octane boosting additives. Tetra Ethyl Lead was the standard octne booster before lead free gasoline was mandated. Then MTBE ( now banned most places) and ETBE were used as lead substitutes.