straight gas vs. 10% ethanol blend

[trollbait]

If the engine has a high enough compression for ethanol octane, you might as well use premium when putting in straight gas.

The mental block people have over premium might be an issue, but it's a moot point. Flex-fuel engines aren't high compression.

[kamesama980]

you DO NOT need a certain compression ratio to run higher octane, only to make it worthwhile. you DO need a certain octane to run higher CR without detonation.

You also have to have engine management capable of running the richer mixtures that ethanol requires (Ethanol stoich is richer than E0...about 9.5:1 vs the usual 14.7:1)

Gasoline distilled from crude starts out about 70-75 octane. other goodies are added to bring it up to 87, 91, race gas, AV gas, etc. Ethanol is just one additive to bring it up there. If you take 87 octane is 87 octane regardless of the ethanol content. E10 87 just has fewer octane boosters other than ethanol.

[SarkOzy]

Just FYI, these stations here in SC that boast "no ethanol" are mostly crocks. A substantial portion of the refined fuel here is imported via the port of Charleston and blended for sale. You can get ethnaol-free fuel, but I can almost promise you it will not be sold alongside regular motor fuels at the pump. Several franchise fuel stops that once sold gasoline as "ethanol free" were uncovered and fined.

Also, unless you physically test every tank of fuel you get, it's inaccurate to assume it's all 10% blended. Usually it varies between 3-10%.

[litesong]

An old thread needing a bump & information:
Go to pure-gas.org to find sources for 100% gasoline(ethanal-free). After listing under 2000 sources, pure-gas.org now has 7600+ addresses, with details, & a great zoomable map. After resisting adding station phone numbers, pure-gas.org now lists phones, as well as computer apps to find 100% gasoline while on the move.
After a careful decade of pencil & paper calculations, 3 of my cars have 8%, 7%, & 5% increases in mpg with careful driving. My new 2013 Hyundai Elantra(Epsilon Lyrae), bad-mouthed & sued for poor mpg by leadfooters, is averaging almost 39mpg from May 2013 to December 2013 with lesser city driving. MPG is now dropping with colder weather, winter gasoline & shorter distances. Pretty sure that 100% gasoline in Epsilon Lyrae is getting 7+% better mpg over 10% ethanol blends.

A non-partisan bill in Congress, introduced by Senator Diane Feinstein, is designed to repeal the EPA mandate to put ethanol in gasoline. This bill & congresspeople are the ones to support, to get ethanol out of our nation's gasoline stocks.

[Jay2TheRescue]

Originally Posted by litesong

An old thread needing a bump & information:
Go to pure-gas.org to find sources for 100% gasoline(ethanal-free). After listing under 2000 sources, pure-gas.org now has 7600+ addresses, with details, & a great zoomable map. After resisting adding station phone numbers, pure-gas.org now lists phones, as well as computer apps to find 100% gasoline while on the move.
After a careful decade of pencil & paper calculations, 3 of my cars have 8%, 7%, & 5% increases in mpg with careful driving. My new 2013 Hyundai Elantra(Epsilon Lyrae), bad-mouthed & sued for poor mpg by leadfooters, is averaging almost 39mpg from May 2013 to December 2013 with lesser city driving. MPG is now dropping with colder weather, winter gasoline & shorter distances. Pretty sure that 100% gasoline in Epsilon Lyrae is getting 7+% better mpg over 10% ethanol blends.

A non-partisan bill in Congress, introduced by Senator Diane Feinstein, is designed to repeal the EPA mandate to put ethanol in gasoline. This bill & congresspeople are the ones to support, to get ethanol out of our nation's gasoline stocks.

Last month I actually spoke at the EPA's public hearing on the Renewable Fuels Standard (which the ethanol mandate is part of).

Personally, when traveling I look at the maps on www.pure-gas.org and determine ahead of time where my fuel stops will be. I can drive from my home in Northern Virginia to Florida on ethanol free.

[rfruth]

A new station near me sells E-85 & I have a FFV, yea !

[Jay2TheRescue]

Just be sure that its cheap enough to offset the drop in mileage you will experience.

[trollbait]

Originally Posted by rfruth

A new station near me sells E-85 & I have a FFV, yea !

Lucky you. I wanted to experiment with it when I had a FFV but the nearest station was in central Philly.

The mpg drop from ethanol blends is not linear with the drop in energy content. When fuel economy is tracked by btu/mile, some blends can rise above than of gasoline for certain engines. It'll be lower by the gallon, so price becomes a factor.

E30 to E40 seems to be the sweet spot. It is also where phase seperation no longer is a concern.

[bostonlion]

Originally Posted by rfruth

A new station near me sells E-85 & I have a FFV, yea !

Let us know how long it takes for your engine to be destroyed.

http://www.godlikeproductions.com/fo...sage795331/pg1

[rfruth]

Okay 32 MPG with regular ole E10 & ~28 with E85 (both measured) E85 is 45 cents a gallon less but ... ((so 6 of 1 half dozen of the other)) so cheap mans alt fuel vehicle