farna, I agree wholeheartedly that "Backwoods"( funny, seems I keep hearing that"phrase"? OH YEAH

,that's me :embarrass ) methods of home production of "Ethanol" is just not what any of us are interested in, but you got the ball rollin' in a good way :thumbup: .First, you had some slight errors that I'd like to address, if I may. You stated that one would need about 2 gallons of Alky to replace 1 gallon of gasoline. True figures that I have at hand were compiled by a gentleman named Marlin Davis, former Tech. Editor for "Hot-Rod" Magazine. This particular issue of "Hot-Rod" with pertinent info on Alcohol fuels was published, Oct, 1989, with the information being found back in the "Pit-Stop" section of the magazine.(Sam... if I'm fixin' to get us in trouble w/ "Hot-Rod", what with copyrights and advertising or whatever, well, do what you gotta do Buddy :sweat: )Ethanol, or "grain-alcohol", has a stoichiometric,(theoretical "ideal") air/fuel ratio of 9:1, which means 9 pounds of air to one pound of Ethanol. Gasoline, as we all remember, would theoredically be "ideal" at or about 14.7:1, thus,in theory, we would need about 63-percent more( a little more than half again as much)Ethanol to fuel the SAME engine. I'll get back to "truly" modifying an engine for making the most of the ethanol fuel in a minute. Stay with me, it'll get better

Anyways, the way a fuel is determined to be a potential energy source,is we use the British Thermal Unit. Ethanol's Btu. rating(the amount of heat required to raise the temperature of one pound of water 1 degree F. ,is 12,800Btu/lb. This figure does not compare very favorably to gasoline's 20,700-Btu/lb.,but once metering circuits and accel. pump modifications have been made (to a carberator), or recalibrating the EFI by means of a custom chip or a little time with the laptop , then the numbers for Btu's(read that "heat"),(No, read that " HorsePower!), are about the same, w/ a small edge going to Ethanol,w/ 1422 Btu's released per pound of air consumed gasoline's 1408 Btu/lbs. of air. And the re-calibration, if Mr. Marlin Davis' figures were correct,(and I believe them to be. I don't have a copy of this one , but if you can find a copy of "Brown's Second Alcohol-Fuel Cookbook", I believe Mr. Brown will back it up for us), the recalibration of a carburator orifice will look something like 60% over original, or 1.6 times the existing hole for gasoline. DON'T confuse Ethanol with Methanol. Methanol is what the Indy-car boys and N.H.R.A. "Sanctioned" alky ranks have run for years. By all authority, it's supposed to be cheaper to make (out of coal or natural-gas)but it's heat numbers are even worse, about 6.4:1,stoichometric. I'll bet that's the Alky you were thinkin' bout haveing twice as much of? Anyways , now for some fun stuff. Nowdays, most people build their "street" engines w/ no more than 9 , maybe 9.5 static compression. You might get by with a little more compresion with a great big over-lap on the cam. Then, whatdaya got? An ill tempered old broad, to say the least. No Vacume. And still on the border-line of detenation and over-heating all the time. And that's on HIS MAJESTY'S ROYAL 93 OCTANE. This nice ,slow buring, 106 octane(@ least 180 proof) that I'm proposing to distill myself just absolutely LOVES 13.5,14, even on up to FIFTEEN to ONE STATIC COMPRESSION. This is where Ethanol really starts to shine.Home-distilled ethanol for a daily driver?....with all that compression? Was a time when I'd have said no way, but now, with the advent of "E-85" on the scene,(basically 85 % Ethanol, 15% gasoline). you could, in theory, do an emergency top-off w/ E-85. You could run it all the time and reap all the benefits, except one. E- 85, in my area, when you can find it, is about as high as mid-grade (89 octane)........which brings me back to where I was all along...trying to save some money.If anyone out there has any access to the chart and graph tables that can be used to figure out the boiling points of certain liquids while under a vacume,(evaporator-core technologies), please post it. .....Yes, Farna, as I stated in the first of this post, I agree with you, old schooling a simple pot boiler w/ a 3/8 copper coil or "worm" off the top for fuel, well ....let's just say those type stills are better left to the part time "Beverage" producers. No I'm looking more along the lines of Twin 10" Rectifier-Reflux Columns feeding an 8 gallon per hour Liquid CO2 filled Heat-Exchanger/Condensor, I just need some help figureing the boiling/letdown temps @ around 20" neg. pressure. If anybodies following me and can help w/the info, I'll build the still, document it,and post the plans for free. What more could you ask for? Later,B.W.B.