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Sadly Gregg has passed away
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Just listened to a National Public Radio feature indicating that Obama and the EPA were pushing for a quick mandatory nationwide change to 15% ethanol mix. It is supposed to improve air quality, boost the economy and lessen dependence on foreign oil sources.

The commentator stated that according to the government all cars from 2001 model year on were suited for that formula, but that auto manufacturers have not been consulted.
 

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Premium Member 2006 SLK350
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From what I know of it, ethanol is a bit of a joke and a bad one at that. Yes it works, but it takes more energy to create energy from ethanol than it provides (it's not as energy efficient per unit volume as gasoline). The other problem is that making ethanol drives up ALL food prices as grains are shifted from direct and and indirect food stuffs to making fuel.

If I'm not mistaken ethanol burns cooler but has a lower octane rating so will bring down the octane rating of what its mixed with.
 

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So all cars built before 2001 are out of luck? Sounds like a feel-good political move to me.

Back in Minnesota ethanol is a big deal and I went many miles out of my way to get non-Oxy (no ethanol) gas, my 1984 Cutlass did not like burning ethanol.
 

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just sluggish performance etc? what's the compression ratio...and carb yes?
Yes it had a carb and was sluggish with the ethanol. It never knocked or had any catastrophic issues, but it was obvious the engine was unhappy. Fuel economy also suffered, which makes sense - ethanol has less energy per volume.

Compression ratio I don't remember, probably pretty low.
 

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Disclaimer: This will be a mildly scientific/technical post but I promise not to be wordy.

The fun molecule added to gasoline is iso-octane, it yields about 50 kJ/g. Ethanol in comparison yields about 30 kJ/g. As you can see, Ethanol contains about 3/5 the amount of energy per gram as iso-octane. This means you need to burn more to get where you are going and there is a bit less "kick".

In regards to the octane rating (I'll rant about this at the end for those interested in discovering how...odd...the octane rating is) of fuels with greater ethanol content, I wouldn't worry about it too much. Remember, the octane rating is a metric that attempts to quantify a fuels likelihood to get overly excited and explode before it's suppose to. I'm not exactly sure what the octane rating of pure ethanol is 99-ish...so my gut tells me it should be OK.

Off Topic -
OCTANE RANT: The octane rating is a misleading number and most people have almost no clue what it means. So in case you're interested...here is how it is done (US/Canada ONLY, Europeans and Aussies don't try this at home).

Step 1: Find the Research Octane Number (RON). To do this you must run your test engine with your test fuel mixture at 600rpm. You then change the compression ratio and see where is misbehaves. You then compare this to a second fuel mixture containing only iso-octane and n-heptane. So say your special fuel mixture misbehaves exactly like 90% iso-octane 10% n-heptane then your RON is 90.

Step 2: Find the Motor Octane Number (MON). You run a similar test engine at 900rpm, use preheated fuel mixture, and variable ignition timing to be extra mean to your fuel. You then compare these results in the same way as step 1 to the iso-octane/n-heptane fuel mixture. This number is typically 6-12 points lower than your RON.

Step 3: Find your Anti-Knock Index (AKI). To find the AKI you simply take the average of your MON and RON. Annnnnnd presto!!! That is the number you see on the pump.

Hope that demystified it for some people.
 

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Ethanol

As far as being a alternative fuel, this is BS. What I've read about it is it takes a gallon of fuel to make a gallon of ethanol. This is Bull...t, all it's doing is subsidizing the farmers. The crap attracts water, so if you car sets the winter, it could coagulate into a glob of crap waiting for your fuel pump or injectors to suck it up.
Corn is 1 to 1 to produce. Sugarcane is 8 to 1, Brazil uses it thru cane.
I have written my senator,Carl Levin, and have gotten no response about this issue. But every other issue I have written to him about he has responded.
As ya'll can see I get fired up about this issue! Ethanol right now is a waste of money, and the price of food keeps going up. Ethanol is part of the problem, not a solution! Write your senators and help stop this crap!!!!:tazz:
 

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Last January Finland change their gas mixes from 95 to E10 (meaning 95 octane with 10% ethanol) and 98 to E5 (98 octane and 5% ethanol). The government had a list for all cars which were not suited for E10 and ALL Mercedes-Benz cars were not suited and recommend they use E5. So unpopular is the E10 that in some rural locations the gas stations have stopped selling E10 due to low demand. Of course I'm using E5 for my SLK but our family Toyota is happy with its E10.
 

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Founding Member #2 2008 SLK55 AMG
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As far as being a alternative fuel, this is BS. What I've read about it is it takes a gallon of fuel to make a gallon of ethanol. This is Bull...t, all it's doing is subsidizing the farmers. The crap attracts water, so if you car sets the winter, it could coagulate into a glob of crap waiting for your fuel pump or injectors to suck it up.
Corn is 1 to 1 to produce. Sugarcane is 8 to 1, Brazil uses it thru cane.
I have written my senator,Carl Levin, and have gotten no response about this issue. But every other issue I have written to him about he has responded.
As ya'll can see I get fired up about this issue! Ethanol right now is a waste of money, and the price of food keeps going up. Ethanol is part of the problem, not a solution! Write your senators and help stop this crap!!!!:tazz:
PAC (Political Action Group) aka political lobby = legalized bribery (trying to make this free from politics).
 

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Sadly Gregg has passed away
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Discussion Starter #10
Hope this is not interpreted as a direct political statement, but politics, ethanol, and gasoline are not mixing too well as evidenced by the ethanol controversy.....

We have grown large quantites of corn for over 150 years here on the prairie in southern Illinois. Farm families really don't care who buys corn or what they use it for as long as we make a reasonable profit. As the previous poster noted, corn supply and demand does influence the cost of virtually every food and drink item you buy from milk, cereal, and hamburger to soda pop....let alone ethanol/gasoline blends.

Do farmers manipulate the supply/demand for corn? Wish we could! Did you know that Uncle Sam pays farmers huge subsidies not to farm good acreage, thereby decreasing supply and increasing cost to the consumer. It's all about corporations and the goverment gaining control over family farms.

Personally, I believe that the free market should drive what gasoline formulations are available for purchase and what that fuel costs. Can't buy the argument that ethanol is environmentally friendly or that it saves the consumer any money in the end. More importantly, if the 85/15 mix messes up my SLK somebody is in big trouble!
:usa:
 

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Founding Member #2 2008 SLK55 AMG
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..... Did you know that Uncle Sam pays farmers huge subsidies not to farm good acreage, thereby decreasing supply and increasing cost to the consumer. It's all about corporations and the goverment gaining control over family farms. .....
Yes and :td: to manipulations by politicians.
 

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From what I know of it, ethanol is a bit of a joke and a bad one at that. Yes it works, but it takes more energy to create energy from ethanol than it provides (it's not as energy efficient per unit volume as gasoline). The other problem is that making ethanol drives up ALL food prices as grains are shifted from direct and and indirect food stuffs to making fuel.

If I'm not mistaken ethanol burns cooler but has a lower octane rating so will bring down the octane rating of what its mixed with.
One thing you won't see is the farmers growing the corn switching their tractors and combines to ethanol power.

Ethanol actually provides greater knock resistance (higher octane) but that's essentially meaningless unless one modifies their engine to take advantage, i.e. raises compression ratio. It for sure would have been a much "nicer" antiknock additive all these years than tetraethyl lead, although I'm pretty sure the required amount is less than 10-15%.

http://online.wsj.com/search/term.html?KEYWORDS=ethanol&mod=DNH_S
 
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