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Ethenol free gas

Joined
Jan 24, 2002
Messages
229
Location
Binghamton, NY
Corvette
1981Dark Blue Metallic & 2004 conv. magnetic red
I have been using 93 octane with 10% ethenol and recently found 3 stations in my area that sells 91 octane that is ethenol free. Been using it in my truck and the milage has improved almost 3 MPG so tried it in the both of the vettes and they seem to run better without the stinky exhaust fumes and moisture dripping out of the tailpipe.

Anyone else doing the same and what are the results?

Chuck
 
I use "pure gas" in my three Chevys and the John Deere and Honda. The mowers start easier, and the mileage is better in the cars. I also don't worry as much about the gas during long term storage, although I still use Stabil.
 
about pure-gas.org

PURE ethanol has a very high octane, about 114, but many mistakenly believe that E10 conventional gas sold has "extra octane" then stated at gas pump.

Regarding octane and E10 gas, buying sub-octane gas is more common, then "extra" octane.

Since ethanol is considered an octane enhancing additive, if/when E10 sold has less than exactly 10%, the result will be sub-octane gas (less than number stated at the pump), AND,
When E10 gas phase-separates (high octane ethanol drops to the bottom of the tank with water), the upper tank layer octane typically drops 2.5 points. E.G. 87 octane gas purchased now becomes sub-octane 84.5 gasoline. E10 gas is available in all grades, including regular-87, premium-91, racing-014, etc.
Testing a fuel sample from tank bottom for alcohol percent will confirm gas contaminated with water, and is not safe for use. After phase-separation upper tank layer typically drops from 10% ethanol to 0-2%, and lower tank layer typically test 60-95 percent alcohol (can/will damage engine). Gasoline Octane and E10 Ethanol Blend Fuels
 
about pure-gas.org

Since ethanol is considered an octane enhancing additive, if/when E10 sold has less than exactly 10%, the result will be sub-octane gas (less than number stated at the pump), AND,
When E10 gas phase-separates (high octane ethanol drops to the bottom of the tank with water), the upper tank layer octane typically drops 2.5 points. E.G. 87 octane gas purchased now becomes sub-octane 84.5 gasoline. E10 gas is available in all grades, including regular-87, premium-91, racing-014, etc.
Testing a fuel sample from tank bottom for alcohol percent will confirm gas contaminated with water, and is not safe for use. After phase-separation upper tank layer typically drops from 10% ethanol to 0-2%, and lower tank layer typically test 60-95 percent alcohol (can/will damage engine).

What absolute gobblegook. Who makes this stuff up? :eyerole

Here's another quote from this site

"An octane number is a measure of gasoline's ability to resist pre-ignition.... "

Ummm, no. It's not pre-ignition at all. It's detonation. Completely different phenomena.

Gasoline Octane and E10 Ethanol Blend Fuels
 
At the end of the day the reality is ethanol has less energy than gasoline.

The energy of ethanol relative to gasoline
A. 76,000 = BTU of energy in a gallon of ethanol
B. 116,090 = BTU of energy in a gallon of gasoline
C. .655 = 2/3 = GGE of energy in a gallon of ethanol. A / B. (GGE =energy in a gal. of gas)
D. 1.53 = Gallons of ethanol with the energy of 1 gallon of gasoline. D = B / A.
With only 2/3 the energy of gasoline, ethanol costs more per mile

Yes ethanol boosts octane but apparently it has less energy per gallon which is why MPG drops by a few percent.

Ethanol has less energy than gasoline and that is a fact. My vehicles no matter if it was my Volvo, my truck, the Corvette or her Edge get less MPG using 10% or less ethanol. The 10% or less is a key and dangerous point.

The pure gas site is written by someone who understands 10% ethanol is lacking as compared to pure gasoline. His main purpose is to distribute where one can buy ethanol free fuels. Past that it is fluff.

The second site I posted is more "correct" as it isn't "fluff" it is fact.

  • Since ethanol is considered an octane enhancing additive, if/when E10 sold has less than exactly 10%, the result will be sub-octane gas (less than number stated at the pump), AND,
  • When E10 gas phase-separates (high octane ethanol drops to the bottom of the tank with water), the upper tank layer octane typically drops 2.5 points. E.G. 87 octane gas purchased now becomes sub-octane 84.5 gasoline. E10 gas is available in all grades, including regular-87, premium-91, racing-014, etc.
  • Testing a fuel sample from tank bottom for alcohol percent will confirm gas contaminated with water, and is not safe for use. After phase-separation upper tank layer typically drops from 10% ethanol to 0-2%, and lower tank layer typically test 60-95 percent alcohol (can/will damage engine).

All gas pumps, at least the ones I've seen state up to 10% ethanol so the first bullet point is correct. That means if you don't get exactly 10% your octane rating is less than.They said it, no one else and it is correct.

E10 does phase separate and that is pure fact. It cannot be debated except with emotion which is not only incorrect; it is waste of time. So the second bullet point is correct.

Although I've never had the time or equipment to sample what is in a gas tank; I do know as the second statement is correct, the third contains a lot of truth.


Yes, I am fully aware of what novices write on the internet. However, the second site I posted isn't a bunch of novices or web authorities.

I am fully aware if I run E85, hit it with meth and have the engine tuned to run it; I get more power.
 
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"Since ethanol is considered an octane enhancing additive, if/when E10 sold has less than exactly 10%, the result will be sub-octane gas (less than number stated at the pump),"

All gas pumps, at least the ones I've seen state up to 10% ethanol so the first bullet point is correct. That means if you don't get exactly 10% your octane rating is less than.They said it, no one else and it is correct.

.

Absolutely not. If the pump says it's 91 octane, it's 91 octane irrespective of what % ethanol they chose to add at the refinery in order to meet production requirements. Production requirements include amongst many other criteria, octane rating. Selling substandard gas is as illegal as short pumping.

Ethanol has less energy than gasoline and that is a fact. My vehicles no matter if it was my Volvo, my truck, the Corvette or her Edge get less MPG using 10% or less ethanol. The 10% or less is a key and dangerous point.

Pure ethanol has 70% of the energy of pure gas. E10 therefore has 97% of the energy of pure gas. That means a car that gets 30 mpg on pure gas will get 29.1 mpg on E10. If you can pick up on variations that small, you're a better man than me.

Testing a fuel sample from tank bottom for alcohol percent will confirm gas contaminated with water, and is not safe for use. After phase-separation upper tank layer typically drops from 10% ethanol to 0-2%, and lower tank layer typically test 60-95 percent alcohol (can/will damage engine).

These sky is falling scare tactics about phase separation are laughable. Sounds like it's written by a high school kid that's never left his mom's basement

1) NO ONE drives around with their gas cap off which would be the minimum required to allow significant moisture to enter and contaminate the gas. Cars since the 60s have had sealed or semi sealed gas caps that allow zero direct inflow of air or only when a slight vacuum is applied. They are not open like some older boats.

2) Supposedly, phase separation will cause the water laden ethanol to sink to the bottom of tank while the gas floats to the top. If this was true, the engine wouldn't start or run. How would it therefore become damaged?

3) Despite 30+ year presence of E10 in North America, the first 20 of which no attention was paid to the above 'issues', genuine real-life problems on cars have yet to surface.
 
I didn't know this was already discussed in length, no my truck does not require 93 octane but tried it. I usually use 89 octang in the truck and 93 in the vettes. I just tried using 91 free gas and maybe my mind is playing tricks on me but they just seem to run better.

A few years ago I taking my boat w/ I/O to launch it and filled up at the gas station, also 2 - 5 gallon cans, it ran like crap but it was so much cheaper than Marina gas. A month later I was putting a rebuilt motor in, cracked block, was that the problem, not sure but never had problems before.

I guess the controversy will continue!

Thanks for your thoughts.
Chuck
 
The auto enthusiast hobby is full of misinformed and misguided information about 'Satan ethanol'. I'm no fan of it but it's better to know the truth rather than believe what some obviously profit-driven vendors try to spin.

This is history sort of repeating itself as similar stories came out in the '70s when unleaded gas first came out. If they had even been half true, all of our old cars would have died a horrid death 35 years ago. :rotfl
 
I burn Ezero almost all of the time because it is readily available where I live. When I leave the state, I'm forced to us E10 for the most part.
So, I notice my fuel mileage on that last tank of Ezero as I head out of state and then pay attention to the mileage I get using the E10.
Generally the E10 reduces my gas mileage by 1-3 miles per gallon when I'm traveling or about 3 to 10% less.

Now if E10 were consistently 3-10% less cost at the pump that would be cool but it's not. E10 around here is priced the same as the Ezero gas. So, I buy Ezero.
In the states and cities where E10 is the only game and there's no Ezero to compare to, I'm stuck with E10 and live with it.
 
Generally the E10 reduces my gas mileage by 1-3 miles per gallon when I'm traveling or about 3 to 10% less.

I have trouble understanding the 10% less mileage theories. That would mean that ethanol (max. 10% of the total fuel volume) contributes nothing in terms of energy, may as well be 'air'.

On my own cars, I don't see enough consistency in fuel consumption to attribute any change to fuel type.
 
Basically my highway mileage dropped about 2 to 3 MPG in the Volvo; so I am about the same as Tuna. My mowers and string trimmers start easily with "pure" gas. Plus they start in Spring without adding Stabil in the fall.
The problem with the math is the experience of too many people causes them to disbelieve the math.

One thing that is being missed is the "up to 10%" if the gas contains less, the octane boost isn't there.

Normal driving is a mix of city, country, and highway as the conditions vary so much you can't get a good average. Less energy means the engine works harder so it ought to use more.

My driving cycle with my truck is up a couple of 6% grades so the transmission is constantly downshifting changing the RPM from 17-1800 to 3000. With the Corvette, it is a Corvette and same as everyone else I step on it too often to bother with MPG.

Lead is a lubricant, it also prevented hot spots on old non-hardened valve seats which has the potential to "pit" the seat; it really isn't a big thing. The pits are small and should not have any effect. Phase separation is a big thing with cars that sit and aren't daily drivers. Phase separation of gasoline and ethanol are not a web legend.

AFA phase separation, one Youtube is worth 10,000 posts: Phase Separation in Ethanol Gasoline - YouTube

Personally, I fill up the cans and Corvette with pure gas before the weather gets bad in winter.
 
My highway mileage dropped 2-3 mpg in all 3 of my vehicles with 10% ethanol, very easy to calculate and verify.

Can't tell much difference in power, but I am sure that it is affected to some degree since the mileage/efficiency has decreased.
 
One thing that is being missed is the "up to 10%" if the gas contains less, the octane boost isn't there.

Lead is a lubricant, it also prevented hot spots on old non-hardened valve seats which has the potential to "pit" the seat; it really isn't a big thing. The pits are small and should not have any effect.

Phase separation is a big thing with cars that sit and aren't daily drivers. Phase separation of gasoline and ethanol are not a web legend.

AFA phase separation, one Youtube is worth 10,000 posts: Phase Separation in Ethanol Gasoline - YouTube

You're just repeating the same myths and misunderstandings without reference to real-life experience. The ethanol phase separation video is a circus side show demonstration. If a gas tank is sealed, there's no water entering.

What's the point?
 
You're just repeating the same myths and misunderstandings without reference to real-life experience. The ethanol phase separation video is a circus side show demonstration. If a gas tank is sealed, there's no water entering.

What's the point?

Leave some gas in your lawn mower for months without stabil and you'll get the point.
 
Ethanol 10 percent

You're just repeating the same myths and misunderstandings without reference to real-life experience. The ethanol phase separation video is a circus side show demonstration. If a gas tank is sealed, there's no water entering.

What's the point?
short note. for the (10) percent fuel issue.. When that's fuel substitute was interdicted . The car industry (old cars) gasket material valve seals etc: disolved to slime..my 65 396/425 for instance from the gas tank ..to the carb.....the gas station I previous used was tested at 21 percent no longer use this store! Fyi. Owner Manuel's for chain saws lawn mowers etc: DO NOT USE...............this product........OLD SCHOOL ....David Sr
 
Leave some gas in your lawn mower for months without stabil and you'll get the point.

This is a car forum. I don't leave any type of fuel in any small engine over the winter. They don't have sealed gas systems like cars which makes all the difference in the world. Here's a picture of the inside of my car's gas tank. The gas is two years old. It's had nothing but E10 since the mid-90s Do you see any water, phase separation or corrosion? :eyerole


gas tank.jpg
 
What Mikey

This is a car forum. I don't leave any type of fuel in any small engine over the winter. They don't have sealed gas systems like cars which makes all the difference in the world. Here's a picture of the inside of my car's gas tank. The gas is two years old. It's had nothing but E10 since the mid-90s Do you see any water, phase separation or corrosion? :eyerole


View attachment 20052
. I have some aviation fuel in my (67) still looks new and the smell!
i don't see any relation to my post for for you to get up in the air about......but this fuel you are so up about cost me a327/340 (eat my original gaskets up. I have owned more Corvettes then the normal gear head! Go NCRS. David Sr
 
.
i don't see any relation to my post for for you to get up in the air about.....

That's because I was replying directly to another poster regarding his statements (as quoted), not yours.

Sorry to hear about your car but I can only imagine that it was equipped with very old hoses and gaskets that might have been due for change anyway. They don't last forever irrespective of what fuel is being used.

Materials used since the 1990s are E10 compatible in almost all cases.
 
Old corvette

That's because I was replying directly to another poster regarding his statements (as quoted), not yours.

Sorry to hear about your car but I can only imagine that it was equipped with very old hoses and gaskets that might have been due for change anyway. They don't last forever irrespective of what fuel is being used.

Materials used since the 1990s are E10 compatible in almost all cases.
Lot of restored corvette's out there from the early 90' beware of the issues. times they are a changen. Thanks take care. David Sr
 

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