pure ethanol and hp,mpg..etc

[curtis73]

Originally Posted by kachok25

OK yall here is the real breakdown of alcohol vs gas. Yes gas has a higher BTU rating than alcohol so in the same eingine gas is more efficent, but that is not the whole story ethanol can run a much higher compression ratio almost the perfect 17:1 where the internal combustion engine makes its peak torque, so if you compared the 10:1 gas engine vs the 15:1-16:1 ethanol engine I honestly don't know which one would burn less fuel given the same load. Here is the kicker for me, alcohol is 1/3 liquid oxygen the same oxygen content of Nitros Oxide this means that it is capable of making about 33% more power than a gas engine even at the same compression ratio! Think your 300hp 350Z is fast, convert it into an alcohol car and it is pushing 400hp with no other modifacation, now increase your CR and you are about 460-480 with no boost and a completly street cam. OR keep the same CR, beef up your internals, and boost it to 19psi and you are making 800+hp. It is the resistence to detonation the makes alcohol a better fuel than gas. From what I understand the reason they are making E85 is because pure alcohol will dry out and crack the rubber gaskets in most gas powerd cars. If alcohol catches on don't be supprised if you see E100 cars in the next ten years.

Wow... um... yes on some, no to the rest.

1- there is no perfect compression ratio where an engine makes torque. The proper compression ratio has to do with cam timing, combustion chamber design, size, and head material, cooling efficiency, projected RPM range, vehicle weight and use, EFI or carb, forced induction or not. To say that there is one perfect compression ratio is very naive

2- Ethanol has about 2/3 the BTU content of gasoline, and its stoichiometric mix is somewhere in the 11.5:1 range. That means its pretty much a wash; you're burning much more fuel of a lower BTU content. The detonation tolerance of Ethanol means you can (actually should) use much higher compression as well. Ethanol is NOT 33% liquid oxygen. Liquid oxygen at atmospheric pressure only exists at -182.962 celsius. There is a small amount of oxygen in ethanol, but not 33% and certainly not liquid. Using the same compression and just switching to ethanol from gasoline WILL NOT randomly make 33% more power, it will make much less power. Car Craft did an in-depth article about the comparison. They built two motors with the same cam and heads. On the gas engine they used pistons for 10:1. On the Ethanol engine they used 13:1. Properly tuned, the engines made almost identical power across the board.

3- The term we're all missing here is denatured. From dictionary.com:

to render (any of various alcohols) unfit for drinking by adding an unwholesome substance that does not alter usefulness for other purposes

Ethanol is drinking alcohol. You are basically putting a highly distilled vodka in your tank. To make it legal for sale, its denatured with anywhere from 5-15% gasoline or other additive. Otherwise you would have all the bums and drunks buying a gallon of pure grain alcohol for $3.

Ethanol is no magic bullet. The problem is production. You can't just look at tailpipe emissions, you have to look at everything in production. Ethanol is rather wasteful. You make a beer from grain (which takes considerable time and resources). At best you can get 13% alcohol content. New yeast strains are becoming available that have pushed it to 13.5 or 14%, but then they die. Then you have to distill it which usually involves large quantities of energy expense. Then you have to distill it at least one more time and you're only ever going to successfully get 95%. Ethanol traps a water molecule inside its own molecule. Getting it out requires a difficult process.

When its all said and done, you get a few gallons of ethanol from hundreds of gallons of beer and the resulting spent beer grain is pretty useless.

[curtis73]

So... to answer the question, jaxtell... Ethanol has much higher resistance to ignition like high octane gasoline does. Most reports put it in the 110 octane equivalent range. But since it has less energy and requires more to be stoichiometric, power output is mostly a wash when you have properly tuned compression for each fuel. MPG you can expect to drop a proportional amount on ethanol.

[tookie-64]

Hi, everyone.I was Readig This Post and had to reply... I live in Minnesota(land of 10,000 taxes) & here we have E-85.I own a 1990 Cougar, a 1995 Explorer, a 1996 Dakota(V-8) & a 1999 Cougar...NONE of them are flex fuel compatible, yet I run straight E-85 in all four vehicles, & have for over TWO & A HALF YEARS! My MPG is a around 4 MPG less on each. I have found that my vehicles only run like crap if I gas-up at a station where they sell little fuel. My vehicles start "Slightly" harder but run good.I ignore the "Check Engine Light" And smile all the way to the bank. In my area E-85 is $ .80 Less Per gallon. Granite Falls Technical College "AUTO MACHANICS" Program Did an independent study on 2 chevy trailblazers on YOU-TUBE.Neather vehicle was flex fuel compatible.They ran one with regular unleaded (85,000 miles) & the Other on E-85 For Over 120,000 miles.THE UNLEADED vehicle failed(Broke Down).They tore Both Moters down and found a much cleaner & less worn motor running E-85.