My experience with E85:
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Better power (cooler intake charge, higher octane and the fact that it is cleaning the engine pretty good).
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Smoother power and better stability at part-load.
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I don´t want to go any higher than 16psi on the stock 13c piece of **** turbo, but it pulls harder and harder all the way to redline.
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After only 50 miles the tail-pipe began to get a lighter color. It was black inside before, now it´s brown and very transparent. My pipe is chromed and now you can see the chrome on the inside as well. When I have driven the car for a couple of 100 miles more I will tell you if it has got any cleaner inside.
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The sound from the engine is different. It sounds more powerful.
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The smell from the exhaust is much nicer. I cant describe the smell, When the car is hot i dont smell anything wierd. BTW i drive without cats.
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The ethanol is cleaner and does not cause problems and if used in an E85 mix it will promote better lubrication of the parts in contact with the mixture and thus, will increase the engine useful life and ensure a significant increase in fuel economy.
Will my O2 sensor work with E85 and high ethanol blends?
The O2 sensor is not an issue, all it cares about is if your at stoich combustion at low throttle settings, it doesn’t much care how you get there, so no need to change it. There is a thread about this on this forum somewhere where i explane this… (see if i can find i later)
What about oil contamination?
Modern lubricants, especially the synthetic oils are much much different than the oils used during those studies, and modern engines run at higher temperatures today which will quickly boil any traces of alcohol out of the oil.
How much will my miles per gallon of fuel drop with E85?
The only negative to E85 is that it gives a lower fuel milage on a gallon for gallon basis to gasoline. The actual difference in energy content between straight gasoline and E85 is about 27%.
The drop in milage is not as significant as you would think based on that difference due to the higher effeciency of the ethanol as a high performance fuel.
The lower milage is not really a big deal, ethanol has lower energy per gallon but your reduction in milage is not nearly as large as that difference would imply. Due to the higher torque,you use slightly smaller throttle openings to get the same level of preformance, and due to the greater quantity of combustion products (more moles of gas) per lb of fuel the engine effeciency actually goes up slightly.
Will a wide band O2 sensor accurately read fuel air mixtures with E85 blends ?
To get an accurate AFR reading you need to switch the meter to Lambda or equivalence ratio setting rather than AFR. Most O2 sensors assume you are running gasoline and will report a stoichimetric mixture as 14.7:1 which is the proper value for gasoline. E85 has a Stoichemetric mixture of between 9.7 - 10:1 and a max power mixture of about 6.98-8.5:1 or so, where with gasoline it is 12.5:1-to 13.1.
If you must use an O2 sensor that only reports gasoline AFR information simply divide the numbers it reports by 1.47 - 1.50.
The O2 sensors would still work. They don’t understand AFR, they only understand rich/lean. If you are using regular or E10 the stoich AFR is ~14.7:1 (as you well know) and when the O2s are switching, this is the AFR it is indicating. When you are using E85 (AFR 9.765:1), the O2s will still work, switching between rich/lean. It’s just that the point they are switching at is 9.765:1. You have to know what fuel you are burning to properly interpret the information the O2 sensors are providing.
Lambda 1 is always Lambda 1 no matter what you drive your car on, the o2 sensor doesn´t care if the AFR are 14,7 or 9.765… it measures the available o2 in the exhaust gases.
Is Ethanol less corrosive than Methanol?
Methanol is much more corrosive than ethanol. It attacks certain soft metals that are not much used in modern fuel systems. Years ago, the carburators were made of un-anodized aluminum and if methanol fuel was used, you had major problems with electrolytic corrosion between the aluminum and copper components used in the fuel system, since they were in continous contact.
That sort of corrosion only occurs when you have a current path between the dissimilar metals AND, a conductive path through the fluid in the system.
In Brazil where they have run high ethanol fuels since 1939, they found that to convert older cars designed for gasoline, long before ethanol blends were common, needed several changes to convert the cars over. This led to changes in valve materials, piston rings choices, nickle plating of the fuel tanks etc.
Modern cars in the U.S. are designed for use with ethanol up to 10% concentration in the fuel. That has led to several changes in component materials over the last 30 years that the U.S. has used ethanol enhanced fuels. All modern fuel lines and such are designed with the expectation that some ethanol will be in the fuel.
What about fuel system corrosion?
Corrosion does not appear to be an issue with modern OBDII cars. They are all certified by the manufactures to be safe to use on 10% ethanol fuel blends, and industry insiders say they are safe for much higher percentages. You don’t install components that are “sorta safe” with a chemical, you put in a fuel hose etc. that is ethanol safe for concentrations well above what you expect to use. Not to mention that folks have been talking for years about raising the ethanol level to 20% or more.
Many years ago there were studies that indicated engines that ran on alcohol ALONE as a fuel, had issues with lubrication and valve seat wear. Keep in mind, those studies were done a long time ago, when engine oils were much less sophisticated than they are now, and some engine manufactures in the 1940’s,1950’ and 1960’s made stupid engineering decisions and did not use hard valve seat inserts like stellite in the cylinder heads. This resulted in valve seat recession problems if you did not have lead additives in the fuel to protect the valve seats.
To sum it all up
Why is Ethanol a better fuel ?
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It has a much higher evaporative cooling power than gasoline so the intake air charge in the cylinder is significantly cooler that it is with a comparable mixture of gasoline — that means higher VE.
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Its octane as blended in E85 is about 100, its blending octane when added to gasoline is rated at 118, so it is a very cost effective octane booster.
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Ethanol burns faster than gasoline but has a slightly longer ignition delay during the slow burn phase of combustion so the engine does not do as much negative work fighting rising cylinder pressures due to large ignition advances. The total ignition advance for E85 is almost identical to the ideal advance for gasoline so it does not cause the PCM problems when you mix them.
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At proper mixture you actually are releasing more energy in the cylinder due to the higher quantity of fuel you can burn. ( Ethanol can burn effeciently at much richer mixtures than gasoline can) That means about a 5% increase in energy release all by itself.
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Peak combustion pressures are actually lower for ethanol than for gasoline but the cylinder pressures stay higher longer, so you have more (longer) crank angle that is usable by the engine. This lower peak cylinder pressure also helps with detonaton control.
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Theorethically, the gain is 5% just by switching fuel. 350 hp X 5% = 15 hp, plus what can be gained from timing.