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NVSmith · 04-29-2012, 03:36 AM

-I think we're working around to saying similar things. A gallon of alcohol does NOT have the BTUs of a gallon of even WalMart gasoline: 76,100 BTU's for ethanol and 114,000 BTUs for gas.

-Pushing more alcohol into an engine burining only alcohol will actually decrease efficiency by preventing burning as the combustion chamber is designed around a certain amount of fuel. Raising the compression ratio works to a point but one source I came across said that 14:1 was about as high as one could go. He figured that alky had 2/3 the power of gas and raising the compression ratio to 14:1 would bring the efficiency up to about 90% of a gallon of gas, which brings it down to a matter of economy. Oh, one site also pointed out that the pumps that have ethanol added actually LOWER the enrgy value of each gallon of gas, which makes sense.

-I have read (Mother Earth News, of course) of modified airplanes and motorcycles crossing the country on pure alcohol.

-Three items for consideration: 1) what about emissions? 2) has an engine ever been specifically designed to run on alcohol? 3) does it have to be an INTERNAL combustion engine?

-I'm going to bed.

04-29-2012, 03:36 AM	#14 (permalink)
NVSmith NVSmith Join Date: Apr 2012 Location: MacDill AFB, FL Posts: 10 Thanks: 3 Thanked 3 Times in 2 Posts	Alcohol, again -I think we're working around to saying similar things. A gallon of alcohol does NOT have the BTUs of a gallon of even WalMart gasoline: 76,100 BTU's for ethanol and 114,000 BTUs for gas. -Pushing more alcohol into an engine burining only alcohol will actually decrease efficiency by preventing burning as the combustion chamber is designed around a certain amount of fuel. Raising the compression ratio works to a point but one source I came across said that 14:1 was about as high as one could go. He figured that alky had 2/3 the power of gas and raising the compression ratio to 14:1 would bring the efficiency up to about 90% of a gallon of gas, which brings it down to a matter of economy. Oh, one site also pointed out that the pumps that have ethanol added actually LOWER the enrgy value of each gallon of gas, which makes sense. -I have read (Mother Earth News, of course) of modified airplanes and motorcycles crossing the country on pure alcohol. -Three items for consideration: 1) what about emissions? 2) has an engine ever been specifically designed to run on alcohol? 3) does it have to be an INTERNAL combustion engine? -I'm going to bed.