Great mileage using 100 percent petrol

[427435]

Originally Posted by litesong View Post
Ethanol btus are efficiently generated in high compression ratio (16:1) ethanol engines. Ethanol btus are NOT efficiently generated in low compression ratio (9:1 to 11:1) gasoline engines.
/////////
427435 muffed:
The compression ratios of E85 cars all fall in the range of 9:1 to 11:1 and all make almost exactly the mpg that one would expect from the BTU's in E85 gas.
/////////
litesong wrote:
E85 ain't 85% ethanol, almost never 80%, seldom in the 70-80%, but often in the 51% to 69% range. Real-world E85(60% ethanol?) mpg most often can't get 70%-75% mpg of E0. Actual E85(85% ethanol-no such animal!) might not get 60% mpg of E0 & probably 50+% of E0 mpg.

In essence, E85 trades on the over-percentage of E0(35-40%) in E85 to raise its mpg, due to poor use(inefficient burning in gasoline engines) of ethanol.

Again, the EPA tests for E85 don't use E-anything fuel. They use E85 with the max allowable ethanol content. The results of those tests are exactly what you would expect from E85 fuel.


Gasoline gallon equivalent tables
GGE calculated for gasoline in US gallons at 114000 BTU per gallon,
or 7594 kilocalories per litre[2] Fuel: liquid, US gallons GGE GGE % BTU/gal kWh/gal HP-hr/gal Cal/litre
Gasoline (base)[3] 1.0000 100.00% 114,000 33.41 44.79 7594.0
Gasoline (conventional, summer)[3] 0.9960 100.40% 114,500 33.56 44.99 7624.5
Gasoline (conventional, winter)[3] 1.0130 98.72% 112,500 32.97 44.20 7496.5
Gasoline (reformulated gasoline, ethanol)[3] 1.0190 98.14% 111,836 32.78 43.94 7452.4
Gasoline (reformulated gasoline, ETBE)[3] 1.0190 98.14% 111,811 32.77 43.93 7452.4
Gasoline (reformulated gasoline, MTBE)[3] 1.0200 98.04% 111,745 32.75 43.90 7445.1
Gasoline (10% MTBE)[4] 1.0200 98.04% 112,000 32.83 44.00 7445.1
Gasoline (regular unleaded)[5] 1.0000 100.00% 114,100 33.44 44.83 7594.0
Diesel #2[5] 0.8800 113.64% 129,500 37.95 50.87 8629.8
Biodiesel (B100)[5] 0.9600 104.17% 118,300 34.80 46.65 8629.5
Bio Diesel (B20)[5] 0.9000 111.11% 127,250 37.12 49.76 8437.7
Liquid natural gas (LNG)[5] 1.5362 65.10% 75,000 21.75 29.16 4943.3
Liquefied petroleum gas (propane) (LPG)[5] 1.3500 74.04% 84,300 24.75 33.18 5625.2
Methanol fuel (M100)[5] 2.0100 49.75% 56,800 16.62 22.28 3778.1
Ethanol fuel (E100)[5] 1.5000 66.67% 76,100 22.27 29.85 5062.7
Ethanol (E85)[5] 1.3900 71.94% 81,800 24.04 32.23 5463.3
Jet fuel (naphtha)[6] 0.9700 103.09% 118,700 34.44 46.17 7828.9
Jet fuel (kerosene)[6] 0.9000 111.11% 128,100 37.12 49.76 8437.7


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

 

[427435]

Of course, NOT!!

Ethanol, with an octane of 114, used(not efficiently burned) in a gasoline engine, suppresses its initial burning in a gasoline engine designed to ignite 87 octane gasoline efficiently. This means the ethanol is late burning & can't take advantage of the power stroke that was designed to burn 87 octane gasoline efficiently. The compression ratio is too low to release ALL the btus available in ethanol, plus what ethanol btus are released in a low compression ratio gasoline engine, are most often released TOO LATE to take advantage of the power stroke. Ha ha ha---many "ethanol in gasoline" industry propagandists talk of the cooling effect of ethanol in gasoline engines, as if it is an advantage. The cooling effect of ethanol used in gasoline engines is more evidence that the ethanol missed the power stroke timing.

Both the oil industry AND "ethanol in gasoline" industry knew all this from the beginning. Both the oil industry & "ethanol in gasoline" industry profit from the inefficiency of ethanol used (not burned efficiently) in a gasoline engine.

Talk about mumbo-jumbo. First, when a fuel burns, all the BTU's are released (the exhaust can't be reignited). But an engine never converts all those BTU's of energy into hp-hrs.

It also sounds like you are laboring under the misconception that higher octane fuels burn slower. That is not the case (at least not with fuels used in car engines). Higher octane only means that the fuel requires a higher combination of temperature and pressure to self-ignite (detonate).


From A Reader: I was just going through some earlier issues of Stock Car Racing and saw the article "Fuel 101" from the Jan. '07 edition. You must have been looking under my hood when you were describing the Hobby Stock motor. My question deals with spark timing and fuel octane. Is there a correlation between the two? When I started racing a few years ago, I was told by an engine builder and a few other racers that 110-octane fuel burns slower, so it needs the spark to happen faster, therefore the timing should be set at around 36 degrees BTDC. What I read in the Fuel 101 article was I shouldn't be using 110 for a stock engine with an aggressive cam. Should my spark timing change when I change to pump gas? Thanks for any guidance on this and for all the other guidance I have already received.
Jerry via e-mail, Crystal River, Florida

The simple answer to the question is, yes, there is a correlation between spark timing, fuel octane levels, and the ability to advance ignition timing. The reader stated in his letter that fuels with higher octane burn slower, but this is not correct. The question demands a more complete answer, as there are more complex issues that need to be defined, explored, and resolved.

Starting from a very high level, we know that as compression ratios climb, the likelihood that we will overextend the range of the fuel becomes more of a probability than a random occurrence, especially if we are using pump gas. This condition can be caused by more than just climbing compression ratios. If the racer applies too much ignition timing to the engine, a variety of things will happen. Cylinder pressures will rise faster as the piston approaches TDC. This means that the fuel will start to burn sooner, due to the advanced ignition timing, adding additional pressure to the combustion chamber as the piston is traveling up the bore.


Read more: http://www.stockcarracing.com/techarticles/scrp_0708_racing_fuel/#ixzz3QRI8FRPf

 

[mf7lakes]

The title of this entire thread is "Great mileage using 100 percent petrol".

For those with the capability/ability to actually pump in the gas to your auto, then drive on the interstate at a steady speed to the next fill-up point, write down the mileage, the divide by the gallons you just pumped into your car, you will get real world, real time, no BS miles per gallon.

If you happen to use NON-ethanol gasoline, you WILL see an increase in miles-per-gallon versus gasoline with ethanol in it.

That is not theory, nor thermodynamics, nor worship-at-the-green-ethanol-church-EPA bull#*it. For myself, the cost of the non-ethanol real gasoline, has not been prohibitive. At least as of last December. I would like to think the cost of REAL gas has gone down also.

Now, I would like to post an article written in the Fayetteville, NC "Observer" a couple of years ago. The article is self-explanatory (at least for those that do not worship at the Church of Perpetual Ethanol)......

The scary truth about ethanol

By Russell Walker
Aberdeen
2-18-2011

Ethanol has been presented to this society as a panacea for our energy problems. Ethanol, its production, and basic chemical and physical nature present some very unfortunate problems as a matter of fact.

The first question that needs to be answered is, if ethanol is so wonderful, why is it limited to 10 percent to 15 percent of the total gasoline volume and not make up 100 percent of the fuel? The answer is that the vapor pressure of ethanol is too low and more than 15 percent in the mix will prevent the car from starting.

Another detail that is never mentioned by the Corn Processors Association, et al., is that about 35 percent of the ethanol is oxygen by weight. Have you ever tried to burn oxygen? It does not burn but it takes up space and weight. You are purchasing a non-combustible portion of a molecule. It is just that simple.

Too much water

The production of ethanol in an aqueous mix presents another unfavorable situation. Because of a phenomenon called "azetropic distillation," ethanol cannot be purified to more than 95.6 percent pure alcohol. The remaining 4.4 percent stays as water. This water still needs to be stored and transported. No one ever mentioned that when you were buying ethanol you were also putting water into your tank.

The water in the fuel attracts oxygen from the air. This oxygen through catalytic action promotes rust on any iron or steel that may come into contact with the fuel. Ethanol, because of an uneven electron balance, is what we call a "polar" molecule. It will dissolve any rubber piping, gaskets or latex materials. You may need to replace existing gaskets and seals with new gaskets made from Viton, Teflon or EPDM. Gaskets of rubber, PVC, cork, leather or plastic need to be removed as they will destruct.

Carbon gives off much more energy per unit weight or volume than hydrogen. Carbon has four electrons in its outer shell, which enters into chemical reactions, while hydrogen only has one. That is why coal will never be replaced by any crazy environmental concept. In fact, many ethanol plants are heated by steam produced from coal.

When people buy this corn-robbing, famine-producing ethanol, they are paying for water and oxygen that do not burn. The water in the ethanol further has to be vaporized during the combustion process, which takes energy from the fuel. This nation will consume more fuel on both a volume and weight basics as a result.

Have you ever heard of water promoting combustion or efficiency? I haven't. Unfortunately, this society is going to have to go through a serious energy crisis before the necessary changes are made by Congress. The situation is not just increasing food prices at your local grocery store or feed at the feed store. We are headed towards a famine as corn is the diet of chickens, horses, cows, hogs and people. Let it begin.

Russell Walker has worked as a chemical engineer for more than 40 years. He lives in Aberdeen.

 

[427435]

The agenda of the above article (and perhaps the person who posted it) is clear from this statement in the article:


When people buy this corn-robbing, famine-producing ethanol,


By the way, you are correct about getting less mpg from E10-------------between 2-3%. Any more is driver and condition variable.

 

[litesong]

Talk about mumbo-jumbo.
It also sounds like you are laboring......

The agenda of the above article (and perhaps the person who posted it) is clear......
getting less mpg from E10-------------between 2-3%.

427435 knows how the "ethanol in gasoline" industry demeans the truth.

Considering that ethanol has an octane rating of 114, blending ethanol with octane 84 E0 to make 87 octane 10% ethanol blend is strongly ineffective from a scientific perspective......84 burning with 114. Of course, ethanol can't function in a gasoline engine designed to burn 87 octane.....& it ain't just 2-3%. Of course again, 84 octane gasoline isn't optimally burning in a gasoline engine designed for 87 octane. Yeah, "octane 87 10% ethanol blend"(made of octane 84 & 114)........THE FAT FAKE FUEL!

 

[427435]

427435 knows how the "ethanol in gasoline" industry demeans the truth.

Considering that ethanol has an octane rating of 114, blending ethanol with octane 84 E0 to make 87 octane 10% ethanol blend is strongly ineffective from a scientific perspective......84 burning with 114. Of course, ethanol can't function in a gasoline engine designed to burn 87 octane.....& it ain't just 2-3%. Of course again, 84 octane gasoline isn't optimally burning in a gasoline engine designed for 87 octane. Yeah, "octane 87 10% ethanol blend"(made of octane 84 & 114)........THE FAT FAKE FUEL!

I sure hope that you aren't involved with the propulsion systems of any aircraft or rockets.

E10 fuel is an homogeneous fuel and burns just as an 87 octane fuel is expected to burn. If it wasn't, the 84 octane part would detonate at the common 10:1 compression ratios in use today.

From: http://www.ethanolrfa.org/page/-/rfa-association-site/pdf/module2.pdf


Characteristics of Ethanol-Blended Fuels
Blending ethanol with gasoline has multiple effects. Ethanol increases the heat output of the
unleaded gasoline, which produces more complete combustion resulting in slightly lower
emissions from unburned hydrocarbons.

In addition to the US, ethanol blended gasoline is used in many other countries.

From: http://en.wikipedia.org/wiki/Common_ethanol_fuel_mixtures

Blends of E10 or less are used in more than 20 countries around the world, led by the United States, where ethanol represented 10% of the U.S. gasoline fuel supply in 2011.[1] Blends from E20 to E25 have been used in Brazil since the late 1970s. E85 is commonly used in the U.S. and Europe for flexible-fuel vehicles. Hydrous ethanol or E100 is used in Brazilian neat ethanol vehicles and flex-fuel light vehicles and hydrous E15 called hE15 for modern petrol cars in the Netherlands.[2]


Again, if the 10-85% ethanol content provided no useful BTU's, all these countries weren't be using it (I don't think there is much corn raised in The Netherlands). Nor would the EPA tests of E85 vehicles get much mpg at all with only 15-16% of the fuel generating useful BTU's.

Lastly, E10 or E85 do not burn as two separate fuels. They burn together as one fuel.

Oh yes, in a previous post it appeared as though you were laboring under the false (common but false) belief that higher octane fuels have slower burn rates. Did you actually believe that?? And you want to claim that "science" says ethanol mixed with gasoline doesn't make sense. Best you learn more about the science of internal combustion engines.

 

[litesong]

E10 fuel is an homogeneous fuel......

87 octane E10 ethanol blend can't be homogeneous...... because it is a BLEND, made up of 114 octane ethanol AND 84 octane gasoline. Not only are you an "ethanol in gasoline industry" propagandist, now you prove yourself to be silly.

In addition to 87 octane E10 ethanol blend being a combination 114 octane ethanol molecules & 84 octane gasoline molecules, the 114 octane & 84 octanes are averages only. In essence 114 octane ethanol is an average octane, with some molecules having lower octanes than 114 & some molecules having higher octanes than 114. As in 114 octane ethanol & maybe worse, the 84 octane gasoline, has some molecules with lower octanes & some molecules with higher octanes.

Therefore, 87 octane average, 10% ethanol blend has some octane molecules BELOW 84 & some octane molecules ABOVE 114 octane. On multiple levels, 87 octane 10% ethanol blend is wildly NOT HOMOGENEOUS.

The above is why many drivers have knocking issues with 87 octane 10% ethanol blends. The 84 octane gasoline (with some molecules below 84 octane) is knocking. Switching to 87 octane 100% gasoline, RAISES the gasoline molecules' octane by 3 percentage points & can end knocking.

All praise to homogeneous 87 octane 10% ethanol blends........ NOT!!!

 

[litesong]

...... if the 10-85% ethanol content provided no useful BTU's......

I never said ethanol provides no useful btu's. Several times I do indicate that ethanol does provide btu's. On numerous occasions you sidewinder state I believe things that I have not posted. "ethanol in gasoline industry" propagandists are good at that.

 

[427435]

I never said ethanol provides no useful btu's. Several times I do indicate that ethanol does provide btu's. On numerous occasions you sidewinder state I believe things that I have not posted. "ethanol in gasoline industry" propagandists are good at that.

Aha, progress. So if the 10% of E10 does produce some useful BTU's, how can the mpg drop 10% as some claim??

And why do the tightly controlled EPA tests show the EXACT mpg figure that would be expected from the BTU content of E85 fuel compared to the EPA mpg with pure gas?

And you still haven't responded to my question as to whether or not you originally believed (before this discussion started) that higher octane #'s meant slower burn rates.

Nor have you come forward with what your agenda is. Is it taking food away from the starving (actually pretty inaccurate); stock or employment with oil related companies; or what?

I'm just a retired engineer and old gear head. What's your angle?

 

[litesong]

Aha, progress. So if the 10% of E10 does produce some useful BTU's, how can the mpg drop 10% as some claim??

....... tightly controlled EPA tests.....

And you still haven't responded to my question.....

Nor have you come forward with what your agenda is. Is it taking food away from the starving (actually pretty inaccurate); stock or employment with oil related companies; or what?

The only progress is you quit lying that I declared ethanol used inefficiently in gasoline produced no btus. My years-long accurate mpg records for both 10% ethanol blends & 100% gasoline for 3 cars, showed mpg drops for 10% ethanol blends to be no more than 8%. So you can quit lying again, that I must answer for people who find greater mpg losses.

Many of your questions accuse, side-track, & slither away from the main issue that adding only 10% ethanol to 100% gasoline, shows mpg drops of 8%, 7% & 5%. As an "ethanol in gasoline industry" propagandist, all your sidewinding questions are not worth consideration, as you attempt to avoid the main topics here.....that gasoline engine engineers designed low compression ratio gasoline engines to run most efficiently, burning 100% gasoline & ethanol doesn't work efficiently in low compression ratio gasoline engines.

As for EPA tightly controlled tests, the EPA has proven for two score years its loose grip on mpg ratings. EPA ratings in the 1970's were balloon inflated. The decades since, show only slight decreases in their puffery. Even with lawsuits that have caused penalties to EPA reputation & auto industry customer paybacks for inaccurate mpg assessments, EPA shows its unwillingness to be an advocate for citizens. So much for your "EPA closely controlled tests"........

______________________________

Help support this site so it can continue supporting you!

 

[427435]

The only progress is you quit lying that I declared ethanol used inefficiently in gasoline produced no btus. My years-long accurate mpg records for both 10% ethanol blends & 100% gasoline for 3 cars, showed mpg drops for 10% ethanol blends to be no more than 8%. So you can quit lying again, that I must answer for people who find greater mpg losses.

Many of your questions accuse, side-track, & slither away from the main issue that adding only 10% ethanol to 100% gasoline, shows mpg drops of 8%, 7% & 5%. As an "ethanol in gasoline industry" propagandist, all your sidewinding questions are not worth consideration, as you attempt to avoid the main topics here.....that gasoline engine engineers designed low compression ratio gasoline engines to run most efficiently burning 100% gasoline & ethanol doesn't work efficiently in low compression ratio gasoline engines.

As for EPA tightly controlled tests, the EPA has proven for two score years its loose grip on mpg ratings. EPA ratings in the 1970's were balloon inflated. The decades since show only slight decreases in their puffery. Even with lawsuits that have caused penalties to EPA reputation & auto industry customer paybacks for inaccurate mpg assessments, EPA shows its unwillingness to be an advocate for citizens. So much for your "EPA closely controlled tests"........

Aha, more progress. Now it's a 5-8% drop in mpg despite only a 3% drop in available BTU's.

But you are still dodging the question of why a controlled EPA test shows that the available BTU's in E85 produce the mpg as one would expect compared to the same engine running pure gas on the same controlled EPA test.

The fact that the published mpg may or may not be the same as you actually get on the road is irrelevant. The tests are the exactly same for each fuel and the results show that ethanol, in solution with gas, produces exactly the results that their combined BTU content would indicate. That's the real FACTS------not some pseudo science about compression ratios and the optimum setups for a single, pure fueled engine.

The fuel is a mixture and the optimum engine setup is determined by the characteristics of that mixture.

And again, do you think that higher octane equals slower burning rates. If they don't change, then the BTU's from the ethanol are available in the combustion cycle as the BTU's from the gas portion (they are actually in solution and burn together as one fuel).

Nor have you been forthcoming as to your "interest" in this discussion. Do you think that ethanol from corn increases world hunger------or what???

 

[litesong]

Aha, more progress. Now it's a 5-8% drop in mpg.....

427435 insinuates, slithers, slips & slides, that I have changed from another percentage difference between 100% gasoline(E0) vs. 10% ethanol blends, to 8%, 7% & 5% difference. Here is a portion of my first post on this thread:

.....I have many years EACH, comparing 10% ethanol blends to 100% gasoline(E0) for 3 cars, showing 8%, 7%, & 5% increased mpg with E0.
//////////////

Ethanol engine engineers & gasoline engine engineers know how to design their specific engines. 100% ethanol works best in high compression ratio(16:1) ethanol engines. 100% gasoline works best in low compression ratio (9:1 to 12:1) gasoline engines. Burning E0, instead of inefficiently using 10% ethanol blends in gasoline engines, increases mpg by 8%, 7% & 5%.

427435 is not quite like a Sidewinder snake. It is very easy to catch 427435 in its errors, insinuations & propaganda.

 

[427435]

427435 insinuates, slithers, slips & slides, that I have changed from another percentage difference between 100% gasoline(E0) vs. 10% ethanol blends, to 8%, 7% & 5% difference. Here is a portion of my first post on this thread:

.....I have many years EACH, comparing 10% ethanol blends to 100% gasoline(E0) for 3 cars, showing 8%, 7%, & 5% increased mpg with E0.
//////////////

Ethanol engine engineers & gasoline engine engineers know how to design their specific engines. 100% ethanol works best in high compression ratio(16:1) ethanol engines. 100% gasoline works best in low compression ratio (9:1 to 12:1) gasoline engines. Burning E0, instead of inefficiently using 10% ethanol blends in gasoline engines, increases mpg by 8%, 7% & 5%.

427435 is not quite like a Sidewinder snake. It is very easy to catch 427435 in its errors, insinuations & propaganda.

Well, backsliding. Instead of discussing the FACTS of repeatable EPA tests, you are resorting to name calling and slander. Rather than go there, I will try and explain it another way (if not for you, than others following this thread).

A car with a 200 hp, 10:1 compression engine needs, perhaps, 30 of that hp to go down the highway at 60 MPH. To hold at 60 MPH, the driver keeps the throttle mostly closed. That engine will produce the 30 hp from a certain amount of Btu's. The engine doesn't care if those Btu's come from E0, E10, E85, or perfume. All those fuels combust the same and engine efficiency is the same. And the peak pressure and the BMEP (look it up) will be the same with all those fuels. And remember that those pressures are far less than at wide open throttle.

And, I believe (but not sure), that the peak pressure will be the same at a part load whether it is 10:1 or 15:1. For sure, the BMEP will be the same regardless of compression.

Lets, move on to an engine with, say, 15:1 static compression ratio. Whether you use heavily leaded gasoline or ethanol, the peak hp depends on the Btu's of the fuel used--------enough lbs of fuel and either fuel will produce the same hp. And at part load, the hp will continue to be proportional to the Btu's of the fuel introduced (at mixtures reasonably close to stoichiometric).

Or, in another way (at stoichiometric), lbs. of fuel x Btu/lb x engine constants equals hp out.


Which is why the REPEATABLE EPA mpg tests with E85 fuel equals about 72% of the SAME TESTS WITH THE SAME ENGINE running on E0---------which is exactly what you would expect by comparing the Btu content of the 2 fuels.


By the way, some of the original posters did claim 10% (or greater) reductions using E10 compared to E0. If you didn't, don't let your panties get in a bunch.

 

[Aquineas]

How about dealing with the FACTS instead. BTU's are BTU's.

Isn't it interesting that you assumed I was referring to you. I mean I was , but it was interesting that you felt the need to defend it.

 

[427435]

Please note that the hp/hr column in the chart below (comparing different fuels) does not show different compression ratios.


Gasoline gallon equivalent tables
GGE calculated for gasoline in US gallons at 114000 BTU per gallon,
or 7594 kilocalories per litre[2] Fuel: liquid, US gallons GGE GGE % BTU/gal kWh/gal HP-hr/gal Cal/litre
Gasoline (base)[3] 1.0000 100.00% 114,000 33.41 44.79 7594.0
Gasoline (conventional, summer)[3] 0.9960 100.40% 114,500 33.56 44.99 7624.5
Gasoline (conventional, winter)[3] 1.0130 98.72% 112,500 32.97 44.20 7496.5
Gasoline (reformulated gasoline, ethanol)[3] 1.0190 98.14% 111,836 32.78 43.94 7452.4
Gasoline (reformulated gasoline, ETBE)[3] 1.0190 98.14% 111,811 32.77 43.93 7452.4
Gasoline (reformulated gasoline, MTBE)[3] 1.0200 98.04% 111,745 32.75 43.90 7445.1
Gasoline (10% MTBE)[4] 1.0200 98.04% 112,000 32.83 44.00 7445.1
Gasoline (regular unleaded)[5] 1.0000 100.00% 114,100 33.44 44.83 7594.0
Diesel #2[5] 0.8800 113.64% 129,500 37.95 50.87 8629.8
Biodiesel (B100)[5] 0.9600 104.17% 118,300 34.80 46.65 8629.5
Bio Diesel (B20)[5] 0.9000 111.11% 127,250 37.12 49.76 8437.7
Liquid natural gas (LNG)[5] 1.5362 65.10% 75,000 21.75 29.16 4943.3
Liquefied petroleum gas (propane) (LPG)[5] 1.3500 74.04% 84,300 24.75 33.18 5625.2
Methanol fuel (M100)[5] 2.0100 49.75% 56,800 16.62 22.28 3778.1
Ethanol fuel (E100)[5] 1.5000 66.67% 76,100 22.27 29.85 5062.7
Ethanol (E85)[5] 1.3900 71.94% 81,800 24.04 32.23 5463.3
Jet fuel (naphtha)[6] 0.9700 103.09% 118,700 34.44 46.17 7828.9
Jet fuel (kerosene)[6] 0.9000 111.11% 128,100 37.12 49.76 8437.7

Or go to:

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

 

[427435]

Please note that the hp-hr/Gal column in the chart below (comparing different fuels) does not show different compression ratios.


Gasoline gallon equivalent tables
GGE calculated for gasoline in US gallons at 114000 BTU per gallon,
or 7594 kilocalories per litre[2] Fuel: liquid, US gallons GGE GGE % BTU/gal kWh/gal HP-hr/gal Cal/litre
Gasoline (base)[3] 1.0000 100.00% 114,000 33.41 44.79 7594.0
Gasoline (conventional, summer)[3] 0.9960 100.40% 114,500 33.56 44.99 7624.5
Gasoline (conventional, winter)[3] 1.0130 98.72% 112,500 32.97 44.20 7496.5
Gasoline (reformulated gasoline, ethanol)[3] 1.0190 98.14% 111,836 32.78 43.94 7452.4
Gasoline (reformulated gasoline, ETBE)[3] 1.0190 98.14% 111,811 32.77 43.93 7452.4
Gasoline (reformulated gasoline, MTBE)[3] 1.0200 98.04% 111,745 32.75 43.90 7445.1
Gasoline (10% MTBE)[4] 1.0200 98.04% 112,000 32.83 44.00 7445.1
Gasoline (regular unleaded)[5] 1.0000 100.00% 114,100 33.44 44.83 7594.0
Diesel #2[5] 0.8800 113.64% 129,500 37.95 50.87 8629.8
Biodiesel (B100)[5] 0.9600 104.17% 118,300 34.80 46.65 8629.5
Bio Diesel (B20)[5] 0.9000 111.11% 127,250 37.12 49.76 8437.7
Liquid natural gas (LNG)[5] 1.5362 65.10% 75,000 21.75 29.16 4943.3
Liquefied petroleum gas (propane) (LPG)[5] 1.3500 74.04% 84,300 24.75 33.18 5625.2
Methanol fuel (M100)[5] 2.0100 49.75% 56,800 16.62 22.28 3778.1
Ethanol fuel (E100)[5] 1.5000 66.67% 76,100 22.27 29.85 5062.7
Ethanol (E85)[5] 1.3900 71.94% 81,800 24.04 32.23 5463.3
Jet fuel (naphtha)[6] 0.9700 103.09% 118,700 34.44 46.17 7828.9
Jet fuel (kerosene)[6] 0.9000 111.11% 128,100 37.12 49.76 8437.7

Or go to:

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

 

[mf7lakes]

Oh for chris-sakes --- no one gives a crap about the hp-per-hr nor do we give a crap about the EP-friggin-A ....... all we care about as per the title of this thread is getting more miles per gallon......... and u ain't gotta be a scientist to do the math of dividing miles by gallons pumped.

 

[427435]

Oh for chris-sakes --- no one gives a crap about the hp-per-hr nor do we give a crap about the EP-friggin-A ....... all we care about as per the title of this thread is getting more miles per gallon......... and u ain't gotta be a scientist to do the math of dividing miles by gallons pumped.

Guess you better go take some classes on design of internal combustion engines along with some thermodynamics courses. If you did, you would understand the importance of the things I've posted.

Even without that education, you should be able to understand the many variables that go into on-road mpg testing and that the tightly controlled (and repeatable) EPA tests are the "Bible" for comparing mpg differences.


If all you want is more mpg, drive slower and accelerate gently. A tailwind also helps.

 

[Billfz1]

Ethanol fuel (E100)[5] 1.5000 66.67% 76,100 22.27 29.85 5062.7
Gasoline (base)[3] 1.0000 100.00% 114,000 33.41 44.79 7594.0
The highlighted items show the real differences in the fuels. HP-hr/gal shows that straight gasoline has about 1/3 more energy to release than ethanol. there are a lot of things to consider C.R., internal friction, breathing efficiency. But it still takes a minimum of about 1/3 more fuel to go anywhere at a given HP running Ethanol. As a blend I am sure the MPG loss is less, but there should still be a loss. the only way that wouldn't be true is if the inclusion of Ethanol improved the engines basic efficiency. Possible but unlikely. Dual fuel engines can't have a C.R. high enough to take advantage of the knock control of straight ethanol because the engine would be likely to detonate on normal gasoline.

Bill

 

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Ethanol fuel (E100)[5] 1.5000 66.67% 76,100 22.27 29.85 5062.7
Gasoline (base)[3] 1.0000 100.00% 114,000 33.41 44.79 7594.0
The highlighted items show the real differences in the fuels. HP-hr/gal shows that straight gasoline has about 1/3 more energy to release than ethanol. there are a lot of things to consider C.R., internal friction, breathing efficiency. But it still takes a minimum of about 1/3 more fuel to go anywhere at a given HP running Ethanol. As a blend I am sure the MPG loss is less, but there should still be a loss. the only way that wouldn't be true is if the inclusion of Ethanol improved the engines basic efficiency. Possible but unlikely. Dual fuel engines can't have a C.R. high enough to take advantage of the knock control of straight ethanol because the engine would be likely to detonate on normal gasoline.

Bill

Last, first. E10 fuel is a blended fuel. It's combustion characteristics are that of the blend------------not two separate fuels. Peak CR's only really come into effect at wide open throttle. At partial throttle, the cylinder is never fully charged and there is never peak compression pressure.

Yes, ethanol blended fuels have less Btu's and Hp-hr/gal than pure gas. The reduction is 2-3% with E10 and about 28% with E85. You can expect similar reductions in mpg.