I didnt address the reason we are putting ethanol with gasoline. Its due to emissions and octane requirements. Gasoline on its own makes carbon monoxide, nitrogen oxides, and particulate pollution, among a bunch of other nastiness. Gasoline on its own also only has an octane rating of about 65, so they need to mix it with something to raise the octane, or we would all have 6:1 static compression engines. They tried MTBE but it was found to cause cancer and other health problems and pollute ground water. They used tetra ethyl lead back in the 60s, but it also caused health problems and now both are banned.

When ethanol burns it only makes CO2, water, and trace elements of a couple other things. Those things are still present in alcohol you drink, and they are part of what causes a hangover. Ethanol is the way they are increasing octane and lowering emissions without killing you or the world we live in.

How well does ethanol work as an octane enhancer? Well if you add 10% ethanol to 65 octane gasoline, you get 89 octane fuel instead of ping happy camel whiz.

Ethanol is not a scam, its not going to ruin your engine, its not anything evil. They dont use high fructose corn syrup to make it, and the corn breaks down into 3 things, CO2, ethanol, and the left over stuff like proteins fats and other stuff that cattle, chickens and hogs eat. 1/3 of it ends up as distillers dried grains(DDGS), an excellent cattle feed since it has removed all the stuff that the cows cant digest. So it isnt just gone once we use it to make fuel. Cattle actually put on more muscle when fed DDGS, and we still export tons of that stuff around the world.

Most of what you have been told is only a means to keep the oil companies supplying you fuel. They want to keep the monopoly and be able to charge whatever they feel like for the crap gas they make. You can make ethanol at home and run it in your car, you cant make gasoline at home, can you? You can build a still and all the related stuff for less than $500 and make your own fuel out of anything with starch or sugar in it, including waste bread, stale donuts and spoiled veggies from the supermarket. Your car will last longer on it, run cooler, and you wont have to worry about how much gas costs. Or you can keep complaining about the price of gas and saying ethanol is a horrible thing. Up to you really.

 

Thumpin, your comment about joules got me curious. Here is what I found.

Gas = 132MJ/gallon
Ethanol = 89MJ/gallon

Ethanol wastes less energy releasing heat than gasoline which means more energy is transferred for use by the engine. It is actually about 32% more efficient; however, as you pointed out, it is a leaner fuel which requires more fuel per volume of air. Ethanol is 9:1 where gasoline is 14.7:1. This means you need 38% more fuel per volume of air. This results in a net loss gas mileage even though it is a power increase. Now, if you do not increase your fuel volume like carburetor engines don't when you put in E85 or 10% ethanol, you are actually getting less power because the engine is running leaner than it would with regular gasoline.

Confusing, I know, but the end result is Alcohol (Methanol & Ethanol) has more power than gasoline, but because the leanest of the fuel is greater than the increase in power efficiency, it will be a net decrease in gas mileage...at least this is my understanding.

Source:
http://bioenergy.ornl.gov/papers/misc/energy_conv.html

 

My rub is ethanol (E85) is it is only as cheaper as it is because it is subsidized by the government. In a free trade situation, it is cost prohibitive. That being said, 10% ethanol gas is not any cheaper, so where is the subsidy going? Not to the user like with E85.

10% ethanol is a total rip both in gas mileage and cost. I am not anti-ethanol. In fact I love race engines running on Alcohol, but the 10% B.S. is a scam. Don't even get me started with what it will do to your boat if you do not realize what you are putting in your tank. I say go E85 or gasoline. I do not care, but get rid of the 10% junk or cut the cost to the user and notify the user with huge letter so they know what they are getting.

 

That is assuming the engine is optimized for gasoline, optimized for ethanol the engine can get better mileage and power than gasoline. Its more than just one thing about a fuel that matters, and running a different fuel in an engine that isnt set up for it will always result in poor economy.

Ethanol can be made commercially for less than $2 a gallon, and even with the tax credit its still far cheaper and requires less subsidy than does gasoline. Count in what it costs for our military to protect the oil fields in the persian gulf, including those of us who are now out of the workforce because of a stupid war over there, and gas is incredibly expensive. You are paying for it multiple times not just at the pump. Nobody is fighting over the stuff you can make ethanol from, and it doesnt have to be a food source.

I agree on pulling the subsidies, but they have to pull them from gasoline and diesel too. The problem with that is it will crash the economy like it did when gas got over $4 and the price of everything went up because the cost of diesel doubled, and everything moves by diesel, either in a truck or a train. The cost of a gallon of gas without subsidies, not including the military cost, is well over $5.00 gallon.

I agree on 10%, why waste time and money on gasoline is my take though. For me its either E100 or if on a long trip away from the still and fuel barrel E85. For performance engines running high compression or high boost, its silly not to consider ethanol since you can get it at the pump in quite a number of places and it is a quality race fuel that costs less than 87. Compare VP red and the cost to E85 and its a bargain.

My engines with low compression burn more ethanol than I would like, that is why I am building my engines with over 12:1 now. Once this GTO is done there is a 302 in the works, it might end up a clevor, and it might just get some cheap aluminum heads, but whatever heads it uses its getting small chambers and dome slugs. The cam will stay on the mild side because it isnt a race engine, just something I want to put on a T bucket we are building. The compression is for ethanol, and that engine might find its way in a Fox Mustang or something similar so I can do some mileage testing with it.

Outboard engines wont heat up enough if run on ethanol unless you restrict the water flow to them, running too cold is a problem for sure. Many things are blamed on ethanol without merit, often its another additive or something else entirely. One thing ethanol will do is clean out any fuel system that has had only gasoline run through it, and clog the filter and injectors with it.

I like the stuff because I can make it for about $.40 a gallon right now, cheaper if I use brush wood instead of propane for heat, and cheaper still when the methane plant starts producing gas and hot water. I can run all my heads from the 60s and my engines will last longer because there wont be thick sludge and carbon build up on everything in them. All the political crap just annoys me, the propaganda from oil companies and others is irritating, but being a business they do what they can to protect their business.

I am in it for me, its the best way I can see to enjoy the cars I have and not have to spend my limited income on gasoline or other energy. If anyone else wants to start making their own fuel, hell I will even build them a small still for the cost of the parts and convert a carb if they send a core and a gasket kit. You source the barrels and find something that nobody wants with sugar or starch in it, like old donuts or whatever. For less than $200 you could start making your own, provided your city/state doesnt prohibit it and you get the permit from the feds.

If it sounds like a lot of work, how many hours do you have to spend at the job to pay for your gas each month? How many hours do you have to work so you can take the Mustang out on a nice weekend? Maybe its just growing up poor and having to do things myself so I could use money for important things that has led me to where I am, but I just hate giving money to someone from another country just so I can drive my car. If I go on a long trip I would much rather have that money go to someone in my country, especially with the way the economy is lately.

 

This is all great info. Thumpin can you sum up everything you said once more (for myself and future readers)? Thanks this is very interesting.

 

I think your point about optimization of the engine for Alcohol (100% Ethanol) is valid, and I started to say that, but got distracted. The get the best use of alcohol fuel, you need higher compression.

One opinion you stated, I do not agree with. Money spent defending oil fields...Money spend defending oil fields will just move to money spent defending corn fields if we switch to ethanol. We cannot grow enough corn to switch the country over to Ethanol...end of discussion. Can we ram up, maybe, but more than likely we will have to import corn, which put us in the same boat, just with another set of partners that we have now with oil.

Finally point, ethanol/alcohol reacts to rubber, metal, and fiber glass differently than gasoline. There is a huge problem with 10% ethanol in big off shore boats because the fuel tanks are made of fiberglass. We test every tank we put in our 28' Betram.

 

The comment about ethanol producing more power is somewhat misleading, as though it were an 'all things being equal' kind of thing. A BTU is a unit of energy, just like a kilowatt. Ethanol produces approximately 35% less energy (whether measured in BTUs or Joules) than the same amount of gasoline. The reason racing engines use ethanol is not because it produces more energy but because it has a higher effective octane rating and allows more compression (thus, all things are not equal). On an engine optimized for ethanol it will produce more power (primarily because of the higher compression and more timing, and perhaps to some extent due to less heat), but if one had the same engine (compression ratio anyway) and ran gasoline with the same effective octane, the gasoline engine would produce similar (if not more) power and more power per unit of fuel. The racing engines optimized for ethanol are able to run higher compression (thus producing more power) than an engine burning gasoline but burn more fuel than if they were burning gasoline. (And I'm assuming the OP isn't running an engine optimized for ethanol.)

In Consumer Reports testing they found that a flex-fuel Chevy Tahoe got 27% less mileage running E85 than gas (which, considering it is 85% ethanol, works out to about the 35% less energy noted above).

http://www.theautochannel.com/news/2...31/020480.html

http://en.wikipedia.org/wiki/E85

Living in Missouri where, until recently, we had 'pure' gas, I have found many times that when I fill up in Illinois (where ethanol has been required for years) my mileage will drop 1-2 MPG (typically from 25 to 23.5-24).

 

Hmmm...now I'm confused on which type of fuel to run in my mustang. 87 or 91?? I know 91 should be more for high compression motors but, how do I know if it's right for my car?? Didn't these older cars run on high premium back in the days?

 

That depends on the compression ratio and how much carbon is in the cylinders. To a degree how big the cylinders are has an effect, a 4" bore is less sensitive than a 4.350" bore. Also octane requirements depend on things like altitude, temperature, humidity, and also on things like load. Roughly, you need more octane at sea level in Florida with 98% humidity and 100F pulling a trailer up a slight grade than you do in Denver when its 50F, 40% humidity and on level ground.

Static compression doesnt change, and when you are under load like wide open throttle going down the drag strip, you need fuel that wont ping. Idling around or doing some light footed street driving with a big overlap cam, you can get away with less octane requirement because the dynamic compression ratio does change with load and RPM.

Figure out your static compression, and then add in if you have aluminum or iron heads, and you can then get a ball park figure of what to run.

 

Please keep in mind that I am just a gearhead who likes to make power, lots of power. I dont grow corn, nor do I get paid anything to promote ethanol. I provide information and you can take from it what you will. Im not trying to persuade anyone, but I will help anyone who wants to run a cleaner burning, easy to make fuel, that can make absolutely stupid amounts of power for cheap.

Energy content is misleading when it comes to gasoline vs ethanol. How much gasoline is wasted heating the water in the cooling system? Most of gasoline goes to making waste heat, that means it is doing less work. It heats the valves, heads, cylinder walls, pistons, and eventually the entire engine, and if left unchecked will seize the engine in a very short time. Heat in an engine isnt a bad thing, but the limitations of gasoline make heat your enemy rather than your friend. More on that in a bit.

Raising static compression ratio (SCR) results in more power requiring less fuel, ie a more efficient engine. Gasoline on its own with no additives like MTBE, ethanol, or TEL, can only withstand around 7:1 SCR max. Sure an engine like that will get you around, but the power will be down and fuel consumption will be up over an engine with higher SCR. Just two points makes a huge difference in power and efficiency. There is an upper limit where SCR doesnt help anymore, but part of where that is depends on the fuel and engine design. In simple terms higher SCR makes more torque, the twisting force that accelerates a vehicle, and thus requires less throttle angle and fuel to do the same work as an engine with lower compression or lower torque.

Straight ethanol engines can run compression over 18:1, and with the right chamber shape sometimes higher to the point where you can run a diesel on ethanol. (Diesel fuel pumps dont get lubricated by ethanol so you need a different fuel system, and ethanol's reluctance to detonate means you need an ignition system to a certain point. But before I get off subject..) Getting gasoline to run over 13:1 isnt easy nor cheap, have you priced C16 lately? E85 will run in 13:1 SCR engines with iron heads quite easily, and it will make great power, and have efficiency close to or better than gasoline in a 9:1 engine. Its also cheaper than 87 octane fuel, so if you can use less and make lots more power, why wouldnt you?

Man I hate a wall of text, so here is a pic to break things up a bit.


Ok that is done. Lets talk about heat for a moment. To a certain extent heat = power. Excess heat = waste unless you have a use for it. If you want to heat the air in large volume great. I want my car to move, and heating the air inside the car is all I care about, and only on days where it is cooler than 60F.

Engines operate more efficiently at temps over 200F, that isnt saying they make more power, they are more efficient. Meaning fuel consumption goes down along with emissions and the oil flows more freely, and a few other things. With a gasoline engine we need to keep the fuel cool, and the air cool to make decent power, hot air in a gas engine costs power and efficiency. We all know this already, right? Vapor lock, pinging, dieseling, all are things we are familiar with in our gas engines, and since we have Mustangs we have a performance bent. We go faster when its cooler outside, and the engine isnt too hot, and the gas is as cold as we can get it. We need the fuel and air to be cold because gasoline doesnt like heat, it will start to boil at a relatively low temperature. Well parts of it will start to boil, some as low as 80F in gasolines of the past, others over 450F. Modern fuel has a low just over 120F due to emissions reasons. That large variance is what causes vapor lock. EFI helps because high pressures raise boiling points, but you are still limited in SCR and the gas engine is going to make an abundance of waste heat.

Additionally gasoline has a very low latent heat of evaporation. Meaning when it vaporizes it doesnt pull much heat out of the air it is mixed with. That means you need an intercooler in a boosted application, and the whole cold air and fuel to prevent problems during operation thing. Ethanol on the other hand has a high latent heat of evaporation, it pulls heat out very fast and in large amounts. Blown cars develop frost on the intake tract on 100F days due to the profound cooling effect of ethanol. Ethanol has a boiling point of 173F, but you can take advantage of that and make more power with greater efficiency. Remember how raising the pressure raises the boiling point? Modern EFI systems raise the boiling point high enough that we can heat ethanol to over 200F.

What use is heating ethanol? Coupled with the way it pulls heat from the intake tract when it vaporises, raising the temperature in a pressurized environment then releasing it into a vacuum enhances the cooling effect as well as making the vapor much smaller droplets. Modern gasoline EFI systems atomize the fuel creating relatively large droplets, and therein lies why gasoline makes so much excess heat. Being large droplets rather than a vapor, gasoline tends to burn around the outside edges of the drop and it isnt completed burning the entire droplet before the power stroke is finished. It is still burning when it leaves the cylinder and that heats the cylinder, valve, and head rather than making power. It also raises emissions due to unburned hydrocarbons being released to the atmosphere. Why do you think a catalytic converter operates at such a high temperature burning what doesnt burn inside the engine?

With heated ethanol the vapor is very fine, and even in large droplets ethanol has different burn properties that allow it to release much more energy in the form of work rather than waste heat. With the very fine vapor fuel air mix, combustion is very efficient and results in more power on less fuel. On a low compression gasoline EFI engine, it is possible to heat ethanol in the fuel rail and get better mileage than it does on gasoline, along with making more power. Now put the same heated fuel EFI system on an engine with 15:1 compression rather than the 8:1 engine, and efficiency goes up even further, as does power.

Time for another pic to break up the wall. Squirrel theme today


So does ethanol have a lower energy content? Sure if you use a very basic method to measure it, but the properties it has work together and if the engine is designed to take advantage of those properties, it will be more efficient than gas engines, make more power on less fuel, and produce profoundly less pollution. That is the thing I have barely touched on, emissions. When you burn ethanol you get CO2 and H2O and trace aldehydes. Do you know who Gordon Cooper is? He was one of the original Mercury 7 astronauts, military pilot and test pilot, been in space, etc. He was working on a jet engine running ethanol in Los Angeles, you know the city that you can see the air and not the hills. They had the test equipment behind the engine and it wasnt reading anything, so they figured it was broken. Then they measured the air going into the engine and found the needles moved and the equipment worked, but the jet running ethanol was burning the crap left in the air and making cleaner air in the process.

If you have an ethanol powered car modern emissions equipment probably wont pick anything up, running E85 you will get some hydrocarbons because of the 15-20% gasoline in it. Some states will fail you for nothing showing on the emissions test. Some states exempt alt fuel vehicles from emissions testing. It varies wherever you go. For me the cleaner air is a bonus, because the state I live in doesnt have testing. What is also a bonus is when you run an engine on ethanol you wont get carbon deposits and black soot all through the engine. That means it will last longer with less wear, because there isnt any sand like grit floating around the oil system and between the moving parts. Engines in Brazil running only on ethanol last 500,000 to a million miles, and they change the oil about every 10,000-15,000 miles.

As for attacking plastics and rubber, there are more plastic and rubber parts that ethanol doesnt harm than there are parts that will survive gasoline. There are a few that can withstand both. Since we are stuck with gasoline for the time being, we need the ones that will hold up to both, and most parts companies make parts that are either good with gas or good with both. If gasoline werent around, it wouldnt be a problem finding parts that survive ethanol. If it were terribly corrosive, would it be in an aluminum beer can? Certain proofs have a tendency to pull aluminum into suspension, usually that is when there is between 10% and 40% of water mixed with the ethanol. Stainless is overkill for an ethanol fuel system, but required for methanol because methanol is very corrosive, and toxic. Ethanol fuel is the same thing as Jim Beam or Jack Daniels, it is just mixed with gasoline or some other substance to render it unfit for drinking, and its usually a higher proof. 200 proof is pure alcohol with no water in it at all, 180 proof is 10% water, 100 proof is 50% water. Water binds with ethanol in such a way that if you add one gallon of water to five gallons of ethanol, you will get substantially less than 6 gallons total.

Sorry about the wall of text. Again.