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Worth repeating. (Originally posted to the AirVW Group)
Alcohol in fuel Alcohol has a lower BTU value than gasoline. Depending on how much they are adding to your fuel, you are going to be seeing less power. Alcohol is hygroscopic; it absorbs moisture and holds it in suspension, further reducing the energy content of your fuel but also exposing your fuel system to corrosion. Alcohol weighs less than gasoline. The stoichiometric ratio of an Otto Cycle engine is based on the MASS of fuel & air. If you have a fuel-injected engine with an on-board combustion-control computer, the system will adjust itself automatically and the only thing you'll notice is that you must now buy/burn more fuel to travel the same distance or do the same amount of work. If you are using a carburetor you will have to re-size your jets to accommodate this lower-energy fuel. Depending on the type of alcohol being used to adulterate your fuel (ie, methanol or ethanol), your fuel will now have a higher endothermic ratio to achieve vaporization. With pure gasoline the endotherm is about 90 degrees on the Fahrenheit scale; alcohol is between 120 and 140. Given that alcohol is also hygroscopic, you will have to re-size your carb & manifold heating arrangement to prevent icing. Alcohol has a higher octane rating than straight-run gasoline (about 120 vs 80). If alcohol is the only fuel you can afford (ie, as with Brazil) then you can increase your engine's compression ratio to take advantage of its higher octane. But this is not practical with an engine originally designed to use unadulterated gasoline. ----------------------------------------- Adding alcohol to gasoline is a TERRIBLE idea, especially for aviation. Large corporations bribed our Congressmen to subsidize the building & operation of the necessary distilleries to ensure a built-in margin of profit. Since the average American is a virtual idiot when it comes to technology, they simply told them alcohol was 'environmentally friendly' to sell this particular scam to the public. In fact, mixing alcohol with gasoline is an environmental disaster since we will now have to burn more fuel (and generate more pollution) to do the same amount of work or travel. The subsidies amount to about seventy cents per gallon of alcohol and are in fact a hidden tax imposed on anyone forced to use this adulterated fuel. -R.S.Hoover |
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On May 28, 10:50 am, " wrote:
Worth repeating. (Originally posted to the AirVW Group) Alcohol in fuel Alcohol has a lower BTU value than gasoline. Depending on how much they are adding to your fuel, you are going to be seeing less power. Alcohol is hygroscopic; it absorbs moisture and holds it in suspension, further reducing the energy content of your fuel but also exposing your fuel system to corrosion. Alcohol weighs less than gasoline. The stoichiometric ratio of an Otto Cycle engine is based on the MASS of fuel & air. If you have a fuel-injected engine with an on-board combustion-control computer, the system will adjust itself automatically and the only thing you'll notice is that you must now buy/burn more fuel to travel the same distance or do the same amount of work. If you are using a carburetor you will have to re-size your jets to accommodate this lower-energy fuel. Depending on the type of alcohol being used to adulterate your fuel (ie, methanol or ethanol), your fuel will now have a higher endothermic ratio to achieve vaporization. With pure gasoline the endotherm is about 90 degrees on the Fahrenheit scale; alcohol is between 120 and 140. Given that alcohol is also hygroscopic, you will have to re-size your carb & manifold heating arrangement to prevent icing. Alcohol has a higher octane rating than straight-run gasoline (about 120 vs 80). If alcohol is the only fuel you can afford (ie, as with Brazil) then you can increase your engine's compression ratio to take advantage of its higher octane. But this is not practical with an engine originally designed to use unadulterated gasoline. ----------------------------------------- Adding alcohol to gasoline is a TERRIBLE idea, especially for aviation. Large corporations bribed our Congressmen to subsidize the building & operation of the necessary distilleries to ensure a built-in margin of profit. Since the average American is a virtual idiot when it comes to technology, they simply told them alcohol was 'environmentally friendly' to sell this particular scam to the public. In fact, mixing alcohol with gasoline is an environmental disaster since we will now have to burn more fuel (and generate more pollution) to do the same amount of work or travel. The subsidies amount to about seventy cents per gallon of alcohol and are in fact a hidden tax imposed on anyone forced to use this adulterated fuel. -R.S.Hoover And not only that, it makes your martini taste terrible. |
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JohnO wrote:
On May 28, 10:50 am, " wrote: Worth repeating. (Originally posted to the AirVW Group) Alcohol in fuel Alcohol has a lower BTU value than gasoline. Depending on how much they are adding to your fuel, you are going to be seeing less power. Alcohol is hygroscopic; it absorbs moisture and holds it in suspension, further reducing the energy content of your fuel but also exposing your fuel system to corrosion. Alcohol weighs less than gasoline. The stoichiometric ratio of an Otto Cycle engine is based on the MASS of fuel & air. If you have a fuel-injected engine with an on-board combustion-control computer, the system will adjust itself automatically and the only thing you'll notice is that you must now buy/burn more fuel to travel the same distance or do the same amount of work. If you are using a carburetor you will have to re-size your jets to accommodate this lower-energy fuel. Depending on the type of alcohol being used to adulterate your fuel (ie, methanol or ethanol), your fuel will now have a higher endothermic ratio to achieve vaporization. With pure gasoline the endotherm is about 90 degrees on the Fahrenheit scale; alcohol is between 120 and 140. Given that alcohol is also hygroscopic, you will have to re-size your carb & manifold heating arrangement to prevent icing. Alcohol has a higher octane rating than straight-run gasoline (about 120 vs 80). If alcohol is the only fuel you can afford (ie, as with Brazil) then you can increase your engine's compression ratio to take advantage of its higher octane. But this is not practical with an engine originally designed to use unadulterated gasoline. ----------------------------------------- Adding alcohol to gasoline is a TERRIBLE idea, especially for aviation. Large corporations bribed our Congressmen to subsidize the building & operation of the necessary distilleries to ensure a built-in margin of profit. Since the average American is a virtual idiot when it comes to technology, they simply told them alcohol was 'environmentally friendly' to sell this particular scam to the public. In fact, mixing alcohol with gasoline is an environmental disaster since we will now have to burn more fuel (and generate more pollution) to do the same amount of work or travel. The subsidies amount to about seventy cents per gallon of alcohol and are in fact a hidden tax imposed on anyone forced to use this adulterated fuel. -R.S.Hoover And not only that, it makes your martini taste terrible. Reminds me of the cotton gin. Who wants a fluffy martini? Dan, U.S. Air Force, retired |
#4
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![]() wrote in message ... Worth repeating. (Originally posted to the AirVW Group) Alcohol in fuel Alcohol has a lower BTU value than gasoline. Depending on how much they are adding to your fuel, you are going to be seeing less power. Alcohol is hygroscopic; it absorbs moisture and holds it in suspension, further reducing the energy content of your fuel but also exposing your fuel system to corrosion. Alcohol weighs less than gasoline. The stoichiometric ratio of an Otto Cycle engine is based on the MASS of fuel & air. If you have a fuel-injected engine with an on-board combustion-control computer, the system will adjust itself automatically and the only thing you'll notice is that you must now buy/burn more fuel to travel the same distance or do the same amount of work. If you are using a carburetor you will have to re-size your jets to accommodate this lower-energy fuel. Depending on the type of alcohol being used to adulterate your fuel (ie, methanol or ethanol), your fuel will now have a higher endothermic ratio to achieve vaporization. With pure gasoline the endotherm is about 90 degrees on the Fahrenheit scale; alcohol is between 120 and 140. Given that alcohol is also hygroscopic, you will have to re-size your carb & manifold heating arrangement to prevent icing. Alcohol has a higher octane rating than straight-run gasoline (about 120 vs 80). If alcohol is the only fuel you can afford (ie, as with Brazil) then you can increase your engine's compression ratio to take advantage of its higher octane. But this is not practical with an engine originally designed to use unadulterated gasoline. ----------------------------------------- Adding alcohol to gasoline is a TERRIBLE idea, especially for aviation. Large corporations bribed our Congressmen to subsidize the building & operation of the necessary distilleries to ensure a built-in margin of profit. Since the average American is a virtual idiot when it comes to technology, they simply told them alcohol was 'environmentally friendly' to sell this particular scam to the public. In fact, mixing alcohol with gasoline is an environmental disaster since we will now have to burn more fuel (and generate more pollution) to do the same amount of work or travel. The subsidies amount to about seventy cents per gallon of alcohol and are in fact a hidden tax imposed on anyone forced to use this adulterated fuel. -R.S.Hoover We saw an experiment where an antiqu indicated horsepower device that was used on locomotives was used and an antique hit and miss piston engine. The indicated power gage plotted piston position vs pressure and the area under the pv curve was power. With as little as 10% ethanol added the loss of power was apparent. We also tried acetone, mek and some other octane boosters. They all had the effect of reducing power. Stu Fields |
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"Stuart & Kathryn Fields" wrote:
We also tried acetone,mek and some other octane boosters. They all had the effect of reducing power. MEK... Nearly $100 for 5 gallons... Ouch... |
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On Tue, 27 May 2008 20:34:40 -0700, "Stuart & Kathryn Fields"
wrote: We saw an experiment where an antiqu indicated horsepower device that was used on locomotives was used and an antique hit and miss piston engine. The indicated power gage plotted piston position vs pressure and the area under the pv curve was power. With as little as 10% ethanol added the loss of power was apparent. We also tried acetone, mek and some other octane boosters. They all had the effect of reducing power. Stu Fields I would think the only time to use alcohol would be if avgas was no longer available. At least then the higher compression engines that can't run on premium auto fuel could still operate. But after all the engine changes were made that are needed. And put up with the shorter range with the same fuel tank capacity. I know one thing you could have tried to get more power, instead of reducing it. Nitro methane! but I'd hate to think what it would do to the TBO of the engine. Probably about the same as a dragsters. One race. |
#7
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![]() "Sliker" wrote in message ... I would think the only time to use alcohol would be if avgas was no longer available. At least then the higher compression engines that can't run on premium auto fuel could still operate. But after all the engine changes were made that are needed. And put up with the shorter range with the same fuel tank capacity. What is the compression ratio for on of the Indy cars? They have been running alcohol for years. It is more an ignition timing and material issue... |
#8
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On Mon, 09 Jun 2008 00:10:42 -0400, Sliker
wrote: On Tue, 27 May 2008 20:34:40 -0700, "Stuart & Kathryn Fields" wrote: We saw an experiment where an antiqu indicated horsepower device that was used on locomotives was used and an antique hit and miss piston engine. The indicated power gage plotted piston position vs pressure and the area under the pv curve was power. With as little as 10% ethanol added the loss of power was apparent. We also tried acetone, mek and some other octane boosters. They all had the effect of reducing power. Stu Fields They had to run a test to find out that? Alcohol contains olny about 60% of the power in gas so the power loss should be quite noticable even with 10%. With E85 you are looking at close to a 40% drop. Roger (K8RI) ARRL Life Member N833R (World's oldest Debonair) www.rogerhalstead.com |
#9
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![]() wrote in message ... On Mon, 09 Jun 2008 00:10:42 -0400, Sliker wrote: On Tue, 27 May 2008 20:34:40 -0700, "Stuart & Kathryn Fields" wrote: We saw an experiment where an antiqu indicated horsepower device that was used on locomotives was used and an antique hit and miss piston engine. The indicated power gage plotted piston position vs pressure and the area under the pv curve was power. With as little as 10% ethanol added the loss of power was apparent. We also tried acetone, mek and some other octane boosters. They all had the effect of reducing power. Stu Fields They had to run a test to find out that? Alcohol contains olny about 60% of the power in gas so the power loss should be quite noticable even with 10%. With E85 you are looking at close to a 40% drop. Roger (K8RI) ARRL Life Member N833R (World's oldest Debonair) www.rogerhalstead.com No we didn't have to run a test. It was just a demonstration of his engine and the internal power measurement device. I had never seen one of these devices work, so it was a interesting thing for me to observe the device in operation with different fuel mixtures. The device had a measure of resolution that surprised me. Further discussions of the technique lead to ideas of how it might be adapted to measure Hp in real time on a Lycoming. Further how might that be adapted to show sticky valves and individual cylinder problems. Stu |
#10
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"Stuart & Kathryn Fields" wrote in message
.. . wrote in message ... On Mon, 09 Jun 2008 00:10:42 -0400, Sliker wrote: On Tue, 27 May 2008 20:34:40 -0700, "Stuart & Kathryn Fields" wrote: We saw an experiment where an antiqu indicated horsepower device that was used on locomotives was used and an antique hit and miss piston engine. The indicated power gage plotted piston position vs pressure and the area under the pv curve was power. With as little as 10% ethanol added the loss of power was apparent. We also tried acetone, mek and some other octane boosters. They all had the effect of reducing power. Stu Fields They had to run a test to find out that? Alcohol contains olny about 60% of the power in gas so the power loss should be quite noticable even with 10%. With E85 you are looking at close to a 40% drop. Roger (K8RI) ARRL Life Member N833R (World's oldest Debonair) www.rogerhalstead.com No we didn't have to run a test. It was just a demonstration of his engine and the internal power measurement device. I had never seen one of these devices work, so it was a interesting thing for me to observe the device in operation with different fuel mixtures. The device had a measure of resolution that surprised me. Further discussions of the technique lead to ideas of how it might be adapted to measure Hp in real time on a Lycoming. Further how might that be adapted to show sticky valves and individual cylinder problems. Stu The old mechanical systems don't do well at higher engine speeds, the signal gets attenuated - pressure tranducers, charge amps, and digital signal processing is the way to go nowadays. Kistler will modify spark plugs with a pressure tap to measure the in-cylinder pressures wihout drilling holes in the cylinder head. -- Geoff The Sea Hawk at Wow Way d0t Com remove spaces and make the obvious substitutions to reply by mail When immigration is outlawed, only outlaws will immigrate. |
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