Fuel & Fuel Additives - Page 2 - Smart Car of America Forums : Smart Car Forum

SuperGeek · 01-17-2009, 02:06 PM

10% ethanol isn't making very big an impact. Ethanol has 30% less energy than gasoline, and a 10% mix means you're losing 3%. Ethanol burns cleaner than the other additive they used in the past, whose name I forgot. 3% loss on 35-40MPG is like 1 MPG. Twitching your foot on the gas pedal makes a bigger difference. Don't stress over these small things. You've made a huge impact by simply choosing a high MPG car. Just live life and enjoy the car for what it is.

**jediknight36** · 01-17-2009, 02:12 PM

Well, if thats true, then Im glad. Ive learned to drive to get great MPGs.

Old smart · 01-17-2009, 02:25 PM

Quote:

Originally Posted by jediknight36

This leads me to a question i had posted months ago: Is there anything a person can do who has no choice buy to buy Gasoline with 10% ethanol in it? I use Chevron that has the same amount of Techron in all three of its choices (Texico has merged, so they have it too). Sure, it will keep the engine clean, but is there anything I can add to cut back on the MPG robbing ethanol?

The 10% that we are stuck with now is a mandate of the Clean Air Act whether is actually necessary to attain local EPA air quality levels or not (they vary by location). Unfortunately, the Act will require a much greater percentages of ethanol in the future just to replace gasoline, unless it is rescinded.

Actually, ethanol has a natural higher octane rating than gasoline, so theoretically, compression ratios can be increased to compensate. There is always a trade-off though. Because corn ethanol has a lot of nitrogen compounds in it (from fertilizer), the increased cylinder temperatures associated with high compression will increase NOx levels. We would be better off with water/alcohol-injected, lean-burn technology when we need some additional performance.

SubSlr88 · 01-17-2009, 02:48 PM

Quote:

Originally Posted by SuperGeek

10% ethanol isn't making very big an impact. Ethanol has 30% less energy than gasoline, and a 10% mix means you're losing 3%. Ethanol burns cleaner than the other additive they used in the past, whose name I forgot. 3% loss on 35-40MPG is like 1 MPG. Twitching your foot on the gas pedal makes a bigger difference. Don't stress over these small things. You've made a huge impact by simply choosing a high MPG car. Just live life and enjoy the car for what it is.

In Denver, way back in the 80's they mandated oxygenated fuels in the 6 counties around Denver to reduce the 'brown cloud' (smog) prevalent there in the winter. The two additives were MBTE (Methyl Tertiary-Butyl Ether) and 10% ethanol. When either was added most folks could lose 8 - 12% in their mileage. Not so good, since at Denver's altitude you already suffered lower mileage. Both of my vehicles showed drops from the standard gasoline; MBTE was around 6% and the ethanol was around 10%. Later it was found that MBTE has some serious side-effects (cancer! - duh) and was removed as a fuel additive.
Here in FL, I suffered a 10% drop in my '04 Murano when ethanol was introduced. And that is using an onboard computer long-term average. I went from 23.8 mpg to 21.3 mpg. Since none of the local stations carry anything but 10% ethanol, there is no choice but to run straight gasoline.

**jediknight36** · 01-17-2009, 02:51 PM

Quote:

Originally Posted by SubSlr88

Since none of the local stations carry anything but 10% ethanol, there is no choice but to run straight gasoline.

So if nothing local carries anything but 10% ethanol, how do you get straight gasoline?

Old smart · 01-17-2009, 03:12 PM

Not including the Clean Air Act mandates, this is what the country looks like: http://www.exxon.com/USA-English/Fil...p%20100102.pdf .

It is dated by a year or so, so it may look different in early-'09.