Ethanol decreases mileage significantly- Mtbr.com
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  1. #1
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    Ethanol decreases mileage significantly

    My Forester was consistently getting between 26 and 30 mpg (up to 31.68) till around Nov/Dec. Then I saw a lot of Ethanol stickers go up at the gas stations I use. I calculate mileage on every tank and soon discovered that my mileage dropped and I get 22-25 mpg, and as low at 20.4 mpg. Tire pressure is the same, air filter is new, and oil is fresh.

    So I talked to the gas station owners, Subaru, and did some reading online. Come to find out that a 10% misture of Ethanol drop MPG by 20-35%. Even my Subaru guy said this is consistent across most of the vehicles he sees after Ethanl is added to gas. So the political push/lobby that says using 10% Ethanol drops foreign oil dependence by 10% is completely BSing. In reality, it causes us to import even MORE oil since Ethanol reduces mileage much more than 10%.

    This Ethanol crap has also raised food prices to the point where people are really being affected- not the ones who make big money but the ones who live from paycheck to paycheck- sad indeed. Anyway, I'm trying to get my mileagae back up and have a solution in play. If it works out, I'll post back here.

    If you have any input, feel free to post.

  2. #2
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    Ethanol has lower energy content by volume than gasoline so it's normal your mileage is lower.
    Generally you will get lower mileage in winter than in summer so that should account for some of the change over the decrease you would normally see.
    Last edited by Surestick Malone; 03-26-2008 at 08:05 AM.

  3. #3
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    Mileage definitely suffers in the winter. I'm just glad I'm not still driving my 2002 Pathfinder though I had it set up so well that I do miss it sometimes.

  4. #4
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    Ethanol does have less energy than gasoline. 10% ethanol will not drop your fuel economy 25-30%, more like 2-3%. If you ran E85 (85% ethanol), then you could expect 25-30% decrease in fuel economy.
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    Odd..I wonder why mine dropped so much. It was the Subaru manager who said he has been seeing this sort of drop right after gas stations starting adding Ethanol to their gas this winter. That is why I started to look into it. Maybe I have more to learn about this and discover other variables.

  6. #6
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    The only good thing about Ethanol is that it gets the "green" vote and votes from the cornbelt. Good for the politicians that is...not so good for you and me.

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    tedsti is correct regarding E85 and the 25-30% decrease in fuel economy. I have heard that approximately E30 is the best compromise between performance gain and fuel economy loss. Note that while your car will get less MPG from E85, it actually runs better and faster on E85.

    I wonder how long ethanol will last when/if the political buzz wears off? Corn prices have already skyrocketed from ethanol fuel. And when people learn that their gas mileage suffers and they end up paying more at the pump than the $3+ per gallon now, I would think the demand will shrink. Unless the price of a gallon of E85 is 25% les than a gallon of gas. I'm starting to see that here in Ohio.

  8. #8
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    How closely do you watch your fuel economy? Have you been tracking it for every fill up for a few years, or do you track it intermittently? Do you have any other winters to compare this one to? What was your mileage like last winter?

    I took a 20% hit (55mpg to 45mpg) this winter due to the cold temps we've had. The car was new last winter and I was learning how to hypermile it so I don't have a good comparison, but I was surprised by the effect of the weather this year. We've been using E-10 in Colorado for over a year now so the decrease might be impacted by a winter fuel blend, but it is not due to the ethanol.

    For the record, I am anti-ethanol so I'm not trying to defend it or anything--just trying to understand what might be driving your FE drop.

    K (bring on the electric car!)

  9. #9
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    It's not just that..

    Quote Originally Posted by Surestick Malone
    Ethanol has lower energy content by volume than gasoline so it's normal your mileage is lower.
    Generally you will get lower mileage in winter than in summer so that should account for some if not all of the change over the %10 decrease you would normally see.
    Ethanol is an oxygenated fuel, and to keep the mixture the same, you need a lot more of it.

  10. #10
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    I'm here to learn; not to bash Ethanol (though it makes sense to) but I chk mileage every tankful. It may be the winter mix of gas and who knows what else but the drop has been crazy- I feel like I'm driving a SUV again, especially when I hit 20mpg last week. I didn't track mileage last winter though.

    Any idea what the winter mix is- is it just Ethanol or other additives?

  11. #11
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    Quote Originally Posted by kristian
    K (bring on the electric car!)
    Burn more coal!
    When I see an adult on a bicycle, I do not despair for the future of the human race. ~H.G. Wells

  12. #12
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    Ethanol will cause a decrease in mileage, as everyone here has said. The amount is debatable, but I have head generally that E85 drops mileage 20-30%, and 10% ethonal is fairly insignificant, 2-5%.

    Winter blends also cause a drop, and winter driving often does as well (letting the car idle to warm up, longer time running in open loop as the engine warms up, etc). I used to track my mileage very carefully in my Jeep when I was really cranking the miles on it. Come winter time my mileage would drop from consistant 16.5 mpg to low 15's, a drop of around 10%.

    I too think the whole ethonal thing is a load of crap. Lower efficiency, higher emissions, uses food resources, etc etc. I heard on the radio the other day (so it may not be true) that if we used 100% of our corn crop towards making ethanol it would only cover 4% of our fuel needs.

    Also, while E85 is higher octane than standard gasoline, it only helps if your engine is setup to utilize that higher octane (higher compression, more timing advance, tighter quench, etc). Putting 105 octane in a car designed to run on 87 will do nothing to increase performance or efficiency. In fact, it may even lose power and efficiency (depending on a number of factors), as the higher octane may not burn as completly before being sent out the exhaust valve.

    And end rant.....

  13. #13
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    Quote Originally Posted by Flyer
    I'm here to learn; not to bash Ethanol (though it makes sense to) but I chk mileage every tankful. It may be the winter mix of gas and who knows what else but the drop has been crazy- I feel like I'm driving a SUV again, especially when I hit 20mpg last week. I didn't track mileage last winter though.

    Any idea what the winter mix is- is it just Ethanol or other additives?
    No idea. A good place to learn is www.cleanmpg.com. Some of the techniques described there are a little extreme for my tastes, but there is a lot of good advice on improving mileage and I've seen a couple of winter mpg posts.

    Quote Originally Posted by cutthroat
    Burn more coal!
    Build more wind turbines! (and burning coal is better than several million internal combustion engines burning foreign oil)

  14. #14
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    Quote Originally Posted by Flyer
    Any idea what the winter mix is- is it just Ethanol or other additives?
    If I find time tonight I'll try and dig up a book that I have that gives fuel specs for states/areas based on time of year. I was really amazed how often blends change, and how locations near each other may use completely different additives/blends throughout the year.

    • Tire pressure is the same, but are you on the same tires?
    • Any trouble codes being spit out?
    • Add any accessories, like a roof rack?
    • Driving a different route than normal, possibly with more stop/go or hills?
    • Driving more agressively? (I can knock the Malibu from 33 mpg to mid 20's by driving a bit harder, and could probably be well in the teens if I drove it like a rental car )
    • You didn't suddenly gain like 400 pounds that the car has to drag around, did you?
    • Time for spark plugs?
    • Running defrost a lot? (some cars run the compressor when on the defrost setting to dry the air blowing in, this is the same as running AC, more drag on the engine and lower mpg)
    • Add any heavy draw electrical accessories like driving lights, giant stereo, beer fridge, etc? Again, causes heavier draw on alternator which in turn loads the engine and reduces efficiency.
    • Cold weather also increases oil viscosities, which means more power needed to move gears/etc thru it. Differentials, transfercase, transmission, and engine all have to deal with this (synthetics help a significant amount when running in cold temps).


    Can't think of any more off the top of my head. I should be getting back to work anyway. Then again, work sucks!

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    Everything is the same- same oil, tires, etc. You did have to bring up the damn 400 lbs though, didn't you?

  16. #16
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    Quote Originally Posted by pimpbot
    Ethanol is an alcohol, and to keep the mixture the same, you need a lot more of it.
    There we go, fixed it....

  17. #17
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    I keep track of the mpg in my subaru pretty religiously, and every year when we switch over to the ethanol blend winter gas, my mileage goes from 28-30mpg to 23-25 mpg. not super significant, but noticeable nonetheless.

  18. #18
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    I wonder how long ethanol will last when/if the political buzz wears off? Corn prices have already skyrocketed from ethanol fuel. And when people learn that their gas mileage suffers and they end up paying more at the pump than the $3+ per gallon now, I would think the demand will shrink. Unless the price of a gallon of E85 is 25% les than a gallon of gas. I'm starting to see that here in Ohio.
    Yeah I hear that, being from Ohio as well.

    I hate ethanol. My jeep runs like crap on 10% ethanol fuel. I've driven countless times on a road trip using a non-ethanol mixture and then the same ride same conditions (oil, tire pressure, weight, etc.) and I get less mileage out of my jeep wrangler with the ethanol mixture.

    I avoid it like the plague. With gas being at the 3.50 mark here in Athens, even if I lose only 25-30 miles a tank (around 10% drop) that is still a gallon of gas each tank fill.
    I am not willing to lose the cash or take the hit.

    I ride my bike as much as I can to get around, but having to wear dress clothes in the hearing and speech clinic everyday makes commuting difficult. Also riding on the highway can be scary with some of the non-caffinated zombies trolling the highways in the wee hours of morning.

    Oh well, ethanol was just a quick band wagon jump for politicians and car makers to cover their asses when the gas prices went through the roof. Energy experts have known for years that ethanol is not the answer. Ethanol was a quick fix with a lot of hype and a lot of lies and people are realizing it.

    We just need to learn to stop driving SUV's. Make the f*(^$ers illegal to own unless you meet a certain requirement or make people pay a higher gas tax or something. That would persuade people to get rid of the gas guzzlers. I know before you flame me that a jeep wrangler is not the most fuel efficient car, but my little 4 cylinder gets good gas mileage compared to a lot of other cars. Besides I do use the 4WD a lot when I go back country backpacking and with the crappy maintenance of our roads in southeastern Ohio during the winter.

    Trust me when I finish med school I will be ditching the wrangler for a more sensible and better gas mileage vehicle.

  19. #19
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    Actually, I have also noticed a seemingly larger drop in mileage this winter. Last couple tanks of gas I rarely went above 3000 rpms or 70 mph and I got about 28 mpg (mostly highway in a Mazda 3 hatch 5-speed). Good but I've been over 30 before without driving this slow. "Normal" driving and I'm not getting any where near 28 mpg. I'm not sure what changes were made to this winter blend vs past blends.

  20. #20
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    I have heard that adding 2-3 ouces of pure Acetone per 10 gallons of gas will increase the mileage. Not sure if that works but if I'm going down to 20 mpg, I'll try it. I just need to do some research on this first.

  21. #21
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    I noticed a hit of about 3mpg this winter in my car (07 Honda Fit, typically average 34mpg suburban mixed driving in warmer months). This is my first winter with the car, so I have nothing else to compare to. I am not terribly sure what fuel blends I end up using. I usually buy from either Shell or Sunoco (the stations on my route from home/work).

  22. #22
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    New question here.

    don't we all love learning from politicians? Hey, Ethanol was good idea in theory... reduce dependence on foreign power, but that wasn't our problem (more like a symptom). The problem is the whole dependence on power...

    I love the idea of BioDiesel, but unfortunately it's doomed to fail in a mass-market. Frankly, I was amazed to see how quickly the general public embraced the idea of Ethanol-Gasoline mixtures in their vehicles...

    To me it seemed like the Chevy and Ford backed it waaaaay to quickly for it to be the cure-all.

    How big of a lobby did the corn farmers have tied up in this push towards Ethanol? (for those of you that have info on that I really would like to know... the question was not sarcastic )
    "Listen, strange women lyin' in ponds distributin' swords is no basis for a system of government!..." -- Dennis the Peasant

  23. #23
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    Quote Originally Posted by cutthroat
    Burn more coal!

    Electric cars are so efficient that even when charged by electricity generated form 100% coal, green house gas emission is much less than gas-electric hybrids.

    And coal comes from this country not the middle east. Yet I would like to see more renewable charing electric cars.

  24. #24
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    Quote Originally Posted by Killroy
    Electric cars are so efficient that even when charged by electricity generated form 100% coal, green house gas emission is much less than gas-electric hybrids.

    And coal comes from this country not the middle east. Yet I would like to see more renewable charing electric cars.

    not exactly a fan of coal here... I mean did you even see Zoolander? that stuff is dirty


    Middle east argument is moot... Oil is oil is oil... we shouldn't use it but we do, Ethanol's popularity was only brought about by the "middle east" argument ...

    I would tell us to all start riding bikes but... ehhh... oh well... START RIDING BIKES
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  25. #25
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    Ehh, E85 DOES drop your mileage like 20 percent. I drive E85 vehicles at work and constantly switch back and forth while traveling. All the vehicles display the same behavior.
    Ethanol sucks.

  26. #26
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    Quote Originally Posted by EclipseRoadie
    Ehh, E85 DOES drop your mileage like 20 percent. I drive E85 vehicles at work and constantly switch back and forth while traveling. All the vehicles display the same behavior.
    Ethanol sucks.

    yeah but all those "flexfuel" badges make the guy driving the Tahoe look like an Eco-Friendly crusader more babes for him
    "Listen, strange women lyin' in ponds distributin' swords is no basis for a system of government!..." -- Dennis the Peasant

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    Totally. He gets like 18 mpg. Eco-crusader.

  28. #28
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    maybe change engine oil to get better MPG?
    I used mobil one synthetic for my subie then one service guy recommended to use motul engine oil. it was expensive but I could get about 20-40 mpg improvement per a tank.

  29. #29
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    From http://www.card.iastate.edu/iowa_ag_.../article1.aspx

    Energy content is typically measured by megajoules (MJ). Gasoline contains approximately 121 MJ per gallon. A gallon of ethanol contains 67.4 percent of the energy content of gasoline so it takes 1.48 gallons of ethanol to replace the energy content of a gallon of gasoline. Greenhouse gas emissions, whether from methane, nitrous oxide, or carbon dioxide, are all measured in units of carbon dioxide equivalent (CO<sub>2</sub>eq). Life cycle analyses of gasoline suggest that transportation of oil, refining oils into gasoline, and burning the gasoline in cars releases 94 grams of CO<sub>2</sub>eq per megajoule. This is the carbon content of gasoline. If corn growth required only photosynthesis, if ethanol were produced using solar power, if corn were instantly transported to ethanol plants, and if no land use changes were needed to grow the corn, then displacing a gallon of gasoline with ethanol would reduce greenhouse gas emissions by approximately 11.2 kilograms (kg) of CO<sub>2</sub>eq.
    However, fossil fuels are used to grow corn and produce ethanol. In addition, using corn to produce ethanol means that fewer acres will be devoted to competing crops, more land will be brought into cultivation, and other uses of corn will decline. The greenhouse gas implications of all these factors need to be considered before we can determine if corn ethanol is a low-carbon fuel.
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  30. #30
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    Quote Originally Posted by havnmonkey
    not exactly a fan of coal here... I mean did you even see Zoolander? that stuff is dirty


    Middle east argument is moot... Oil is oil is oil... we shouldn't use it but we do, Ethanol's popularity was only brought about by the "middle east" argument ...

    I would tell us to all start riding bikes but... ehhh... oh well... START RIDING BIKES

    I'm just saying that filling your car with electricity is a much better energy carrier than gasoline, diesel, ethanol, biodiesel and hydrogen even if you have to use the dirtiest power production there is, coal. Another bonus is that electricity is produced domestically, which increases national security.

    Go ask John Whoolsey, former director of the CIA. He advocating Plug-in Hybrids in a strong way .



    That is 100 MPG you see in the picture.

  31. #31
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    Yeah, that's what I said

    Quote Originally Posted by adam728
    There we go, fixed it....
    Alcohol is an oxygenated fuel, BTW. Gasoline is not.

  32. #32
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    I'm tempted to build my own electric plug-in to augment my gas guzzling SUV when I'm not using it for work or bike shuttles. There are entire websites dedicated to DIY electric and hybrid vehicles. It doesn't seem too hard for someone with their own tools and shop space.
    There are no stupid questions but there are A LOT of inquisitive idiots.


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  33. #33
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    Quote Originally Posted by pimpbot
    Alcohol is an oxygenated fuel, BTW. Gasoline is not.
    That's right. And some environmentalists favor ethanol over diesels because it is water soluble with that extra oxygen and bio diesel is not.

  34. #34
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    Quote Originally Posted by havnmonkey
    To me it seemed like the Chevy and Ford backed it waaaaay to quickly for it to be the cure-all.

    How big of a lobby did the corn farmers have tied up in this push towards Ethanol? (for those of you that have info on that I really would like to know... the question was not sarcastic )
    I think your first point here is more important than your second point. If the domestics could make small modificaitons to the hoses and ECUs on their big SUVs, then they don't NEED to embrace new fangled stuff like hybrid technology or anything.

    The farmers do have a lobby for sure, but that lobby was pretty ineffective (see corn prices in the 90s for an example). The biggest thing is that as a population, we're pretty easy to scare (MTBE, foreign oil, global warming, etc.) which plays right into the snake oil (I mean ethanol) solution.

  35. #35
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    Reasons that winter decreases fuel economy are primarily related to cold air and increased friction. The cold air is denser which increases wind resistance, this will affect highway mileage more than city. The cold, denser air also increases throttling losses in the engine which reduces it's efficiency. Cold air intakes may increase power, but they decrease fuel economy. Cold tires also have higher rolling resistance. All this can easily amount to a 10% drop in fuel economy in the winter.

    If you really want better fuel economy, move to CO. The high altitude can get you a 20% increase.
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    Glad to hear it wasn't just me. My Mazda 3 has been getting subpar fuel economy and I couldn't quite figure out what it was... Granted Canadian winters do a number on the fuel economy apparently so does ethenol.

  37. #37
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    Huh?

    Quote Originally Posted by tedsti
    Reasons that winter decreases fuel economy are primarily related to cold air and increased friction. The cold air is denser which increases wind resistance, this will affect highway mileage more than city. The cold, denser air also increases throttling losses in the engine which reduces it's efficiency. Cold air intakes may increase power, but they decrease fuel economy. Cold tires also have higher rolling resistance. All this can easily amount to a 10% drop in fuel economy in the winter.

    If you really want better fuel economy, move to CO. The high altitude can get you a 20% increase.
    Cold air actually increases power, tho. As in, there is more air making its way into the engine to get fuel added and burned. That's why all the ricer street racer tuner guys install cold air intakes on their cars and bypass the intake heater (which is basically a small sheet metal air box around the exhaust manifold with a hose to the air filter). If you drive a manual, more power can let you upshift to the next gear sooner, saving gas. High altitude air would give you better gas mileage only beacuse there is less air and fuel being burned at full throttle. Effectively, you are choking off the engine.

    Cold tires actually have less rolling resistance because they would be harder, and deflect less while rolling. Again, I don't think it is significant at the temp differences we are talking about.

    Air pressure doesn't make that much difference on fuel economy, at least not at the altitudes we are talking about. If you made a road at 30,000 feet, it would.

    I tend to get better gas mileage in winter... granted California Bay Area winter.... comparing cold dry days (30-40F), with warm summer days (90+F).

  38. #38
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    Quote Originally Posted by pimpbot
    High altitude air would give you better gas mileage only beacuse there is less air and fuel being burned at full throttle. Effectively, you are choking off the engine.
    High altitude helps in 2 ways. You are actually choking off the engine less. With less dense air, you need more volume to make the same power. To get more volume you run with the throttle open farther, which reduces your throttling(pumping) losses. The altitude also reduces the wind resistance which is proportional to air density.

    Quote Originally Posted by pimpbot
    Air pressure doesn't make that much difference on fuel economy, at least not at the altitudes we are talking about. If you made a road at 30,000 feet, it would.
    In Denver the altitude is about 5200 ft. The air pressure is almost 20% less than what it is at sea-level. This means that the wind resistance is 20% less and wind resistance is a major player in highway fuel economy.
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    I was all packed up and ready to move to Colorado and then BAM- I realized I live here already, thank goodness!

  40. #40
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    Quote Originally Posted by Flyer
    I was all packed up and ready to move to Colorado and then BAM- I realized I live here already, thank goodness!
    LOL! Me too!

    Actually, we don't have a 20% greater efficiency at altitude--our cars just push 20% less air around (I've heard 30% for Colorado Springs and 50% at 14,000 feet). That wouldn't amount to a whole lot of gain unless you were travelling pretty fast. I don't notice a huge difference in my mileage between sea level and 6,300 feet really, ...

  41. #41
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    Quote Originally Posted by Killroy
    That's right. And some environmentalists favor ethanol over diesels because it is water soluble with that extra oxygen and bio diesel is not.
    biodiesel is biodegradable.. why do you think that increased water soluble would be a sought after parameter?

    more so, what extra oxygen? ethanol has one oxygen.ch3ch2oh fames have two oxygens.. typically CH3OCORx when the reaction is performed using methanol (most common pathway)
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  42. #42
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    Quote Originally Posted by sportsman
    biodiesel is biodegradable.. why do you think that increased water soluble would be a sought after parameter?

    more so, what extra oxygen? ethanol has one oxygen.ch3ch2oh fames have two oxygens.. typically CH3OCORx when the reaction is performed using methanol (most common pathway)

    Think Oil spill.

  43. #43
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    Quote Originally Posted by kristian
    LOL! Me too!

    Actually, we don't have a 20% greater efficiency at altitude--our cars just push 20% less air around (I've heard 30% for Colorado Springs and 50% at 14,000 feet). That wouldn't amount to a whole lot of gain unless you were travelling pretty fast. I don't notice a huge difference in my mileage between sea level and 6,300 feet really, ...
    When I drove from CA to CO a couple of years ago, I noticed my truck's mileage increase from 14mpg to 18mpg during that leg of the trip. I had it loaded with about 1000# of assorted equipment and tools to be delivered to a customer in Pueblo. Oh, the good old days...gas was less than $2/gal then.
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  44. #44
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    Quote Originally Posted by Killroy
    Think Oil spill.
    think biodegradable
    "The search for a perfect pint should take lifetime." M.Jackson

    Ride bikes, not goats. Just good advice

  45. #45
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    Quote Originally Posted by pimpbot
    If you drive a manual, more power can let you upshift to the next gear sooner, saving gas.
    Everything else you said was true, but this is not true. More power means you're burning more gas, your fuel injectors compensate to increase the fuel going to the engine if the air is more dense, and you burn more fuel, it doesn't make your engine any more efficient in terms of milege when it's sucking in colder air. Thermal efficiency may be better, allowing the engine to make more power, but that doesn't mean that your milege goes up, it goes down because you use that "extra power", and no matter how "carefull" you are, it's pretty proven that we aren't really capable of modulating the gas pedal to really bring the efficiency back down to what it is when it's not cold. This is especially true with cruise control. If you could limit your cars power output through electronics or something then it might be possible, but you'd still have that extra air resistance to deal with of course.

    Something that sometimes suprises people though is that many subie owners note better milege after putting on a bigger turbo, due to the increased lag time before the turbo spools up, so if you aren't driving around with a lead foot you actually get better milege, and this is easier to do than the above senario because the bigger turbo increased the lag and you can drive and keep RPMs above whatever the borderline is for the turbo to kick in to a big extent, it also produces pretty hot air (which is cooled usually by an intercooler, but can still end up pretty warm) which is better for milege. While a turbo car can and will eat gas much faster than a NA car, it can be a lot more fuel efficient than a "big" engine that produces a lot of horsepower. It basically turns into that "big" engine when it needs a lot of HP by sucking in as much gas and air as a big engine, but then when the power's not needed it consumes fuel like the tiny engine it is.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  46. #46
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    Quote Originally Posted by Jayem
    ...
    it, it also produces pretty hot air (which is cooled usually by an intercooler, but can still end up pretty warm) which is better for milege. While a turbo car can and will eat gas much faster than a NA car, it can be a lot more fuel efficient than a "big" engine that produces a lot of horsepower. It basically turns into that "big" engine when it needs a lot of HP by sucking in as much gas and air as a big engine, but then when the power's not needed it consumes fuel like the tiny engine it is.
    Jayem, you are cool.

    I agree. I have noticed that Honda Insight owners and I suspect other hypermilers are installing custom "hot air intakes" on there rides to squeeze more efficiency. Apparently 70 mpg is not enough, HA! I have not seen gains, but not very significant gains and I wonder if the armature tests that have been done have good controls to compare. There are so many variables.

  47. #47
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    Quote Originally Posted by Killroy
    Jayem, you are cool.

    I agree. I have noticed that Honda Insight owners and I suspect other hypermilers are installing custom "hot air intakes" on there rides to squeeze more efficiency. Apparently 70 mpg is not enough, HA! I have not seen gains, but not very significant gains and I wonder if the armature tests that have been done have good controls to compare. There are so many variables.
    Well, it's all a compramise. Toyota could make a prius to get even better milege, or honda could do better with the insight, but it's a compramise, and they figure that people won't buy the car unless it will do at least 80mph and accelerate to speed decently.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

    You're turning black metallic.

  48. #48
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    Quote Originally Posted by Jayem
    Well, it's all a compramise. Toyota could make a prius to get even better milege, or honda could do better with the insight, but it's a compramise, and they figure that people won't buy the car unless it will do at least 80mph and accelerate to speed decently.
    UGH....TELL THAT to my blockhead buddy. He told me a Prius couldn't get up a hill (AT ALL) without getting a real good running start. He also said that they could have made it fast while still keeping the same economy.....this is the same guy who bought an 5.0 explorer because he said that he would need a lot of room for beach trips (which occur twice a year). It seems like a lot of people own certain vehicles for rare occasions, like buying a large pickup so they can haul stuff, use it once a year for that purpose, and call it justified.....ITS CALLED A RENTAL PEOPLE! Sorry to get off topic. end rant.
    My epiglottis is full of bees!

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  49. #49
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    UGH....TELL THAT to my blockhead buddy. He told me a Prius couldn't get up a hill (AT ALL) without getting a real good running start. He also said that they could have made it fast while still keeping the same economy.....this is the same guy who bought an 5.0 explorer because he said that he would need a lot of room for beach trips (which occur twice a year). It seems like a lot of people own certain vehicles for rare occasions, like buying a large pickup so they can haul stuff, use it once a year for that purpose, and call it justified.....ITS CALLED A RENTAL PEOPLE! Sorry to get off topic. end rant.
    Yeah. I own a jeep wrangler and would love to have a truck, but you know what I do when I need a truck bed? I rent a trailer or use my father's short trailer and hook it up to my hitch and bam I have a truck bed.

    People really need to learn one word U-Haul

  50. #50
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    It does not seem to follow the law of thermodynamics to loose more than 10% mpg because of 10% ethanol. If this were the case, you'd better off pumping in 10% less gas and just hold the ethanol...

    I guess it really depends on what 10% means. If its by volume or mass or what.

  51. #51
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    Quote Originally Posted by dnoyeb
    It does not seem to follow the law of thermodynamics to loose more than 10% mpg because of 10% ethanol. If this were the case, you'd better off pumping in 10% less gas and just hold the ethanol...

    I guess it really depends on what 10% means. If its by volume or mass or what.
    ECUs are programed though to feed gas to the cylinders, if you start Fing with that formula I'm sure you start to have problems, and while you might be able to minimize that milege loss, it may only be really possible with an (usually expensive) ECU flash or some type of reprogramming. Otherwise the ECU is very particular about parameters and metering the amount of fuel and air going into the cylinders and adjusting other parameters like timing and so on. Pour something in there that wasn't originally thought of from the inception of the vehicle and you might see something a lot greater than a 5-10% loss.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

    You're turning black metallic.

  52. #52
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    I had an FFV 98 Explorer before E85 was the cool fuel, that said in the owner manual that your gas mileage will decrease by at leat 20% if using E85. If we really want to save gas we should be moving to clean diesel technology and use bio-diesels for fuel instead of ethanol .

  53. #53
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    Naa, ECUs are adaptable. Thats the whole point of them. They can adjust to compensate for the type of ignition and temperatures they are seeing from the fuel. I agree that if you pure something in there that blocks the ignition of the gas, then you are going to loose MPG. In that case once again, your better off just pumping in 10% less gas.

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