How did you do that?

 

My first job as a chemical engineer was with Exxon. I heard a lot about gasoline from the experts at the refinery. All east coast oil is pooled by a consortium of the major oil companies. The individual branding is accomplished when a quart of each brands special additive is poured into the shared base gasoline in the tank truck. The other variable is due to state and regional laws which may require or ban the use of certain additives. It is true that oil sourced from the north sea area is naturally low in sulphur, but that is more likely to go to the east coast rather than the west cost. The engineers in the test labs prefered Shell, Texaco,and Amoco. BTW Exxon and Mobil are exactly the same gas.

 

The October issue of Consumer Reports did a study on E-85 (85% ethanol/15% gasoline). They did their test with a 2007 Chevy Tahoe running the 5.3 L V-8. Their fuel mileage dropped 27% using the E-85. The average miles per tank was 440 on gasoline. That fell to just 300 miles per tank with the E-85. The bonus is, they gained .1 of a second on the 0-30, 0-60, 45-65, and quarter mile times.

- city mileage went from 9 to 7
- highway mileage went from 21 to 15
- 150 mile combination trip went from 18 to 13
- overall went from 14 to 10

This gives you an idea where your mileage went, on a larger scale.

 

I agree. The same with this ethanol deal. It takes a lot more energy to refine it and your milage drops 10-15%. Another eco-whacko scheme to help subsidize our farmers and cost the users dollars.

 

The northeast has too much of a 'Not In My Backyard' mentality. Therefore, they get their gas from a big-a pipeline that runs from the gulf coast. Yes, it all goes through the same pipeline. It is pumped with a turbulent flow, so when the blend being pumped is changed it doesn't mix anywhere but at the fluid contact. This pipeline has, like, a 3 foot diameter and runs to some place in New Jersey, I think. That area anyway.

Also, the octane increase is all in the refining. If you take an average barrel of oil and let it naturally separate (gravity) you get about 40% gasoline and a lot of product that is essentially useless. The idea behind a more complex refinery is to make the useless product more useful. Through a few different types of processes the same barrel of oil will make over 70% of a barrel of gasoline. The process known as reforming is generally responsible for increasing the octane. Again, using the crude that was there from the beginning.

 

Very interesting.. what do they do with the rest of the useless stuff?

 

It isn't really useless, just not useful as fuel. It also depends on the crude used. The average barrel of oil using the older processes made: 58% gas, 9% kerosene, 24% distillate fuels and 10 residual oils. That was about 20 years ago. I can't find the entire statisical build up for a barrel at the moment. The processes change constanly depending on the refinery and the crude used. It is actually a very efficient process, nothing is wasted if that is what you are wondering. Even in sour crudes, the elemental sulfur is recovered, as well as the small amount of metals contained. Of course, the residuals are used to make plastics, waxes, perfumes and some of the more 'modern' materials.

 

Regardless, I like using the ethanol. It's just the state of mind knowing we don't need to depend on oil from overseas.

 

You think 10% of gas in a few states and 85% in fewer states keeps us from depending on oil from other countries? Why do you think we are changing the goverment over there, so we can get some politicians in there to give us good prices on that sweet crude.


Spend more to make a product that costs the same but delivers less. Sounds like a sound plan.

 

I don't know about that theory. We can't drill for our own oil in Alaska, off the coast of California or in the Gulf of Mexico but the Mexican's can and so we buy it from them. We are buying ethanol which takes .6 gallons approximate to produce a 1 gallon...and will be paying higher prices for food because the price of corn has gone up which feeds the cattle and poultry we all eat because of the demand for ethenol.

We end up buying ethonal gas which gets worse miliage so we end up burning more fuel. This ain't adding up for me.

What am I missing?

Norm

 

I use Sunoco 94 in the summer heat. Until I started using this fuel I always had a black carbon build up on the exhaust tips. After two tanks the carbon came off easily with a little steelwool and now washes easily. It contains up to 10% ethanol, per Sunoco. Did not notice a difference in mileage, but then I don't care that much about that. Perfer to have no knock.

 

Thank G-D for knock sensors and computers. I put anything in my Vette as long as it says 93 octane. When I drive to Key West from New York City I buy gas when I need it. If you are that concerned about knock put in an octane booster. I have never had a problem with fuel in 36K!
Once I told a gas attendant (in New Jersey) to put in Premium, I ran to the rest room, and when I got back he filled the tank with regular. Vette ran OK and never heard a ping or knock!!!!!

 

Let me bore you with the engineering numbers behind ethanol and gas. This does not take into account the burning efficiency of the fuel injected motor.

Ethanol BTU per gallon: 75.7K BTU
Gasoline BTU per gallon: 125K BTU

So you see it takes 1.5 gallons of ethanol to give the energy of a gallon of gasoline.

Now at 15% Ethanol in a gallon of E85:
BTU of the 85% gas contribution: 106K BTU
BTU of the 15% ethanol contribution: 11K BTU
For a total BTU for a gallon of E85: 117K BTU

This is a drop in energy total of 6.5%.
So what accounts for the 10% drop?
Rough calculations are that energy losses in the car are as follows:
Engine: 62%
Drive Train: 5.6%
Aero drag: 2%
Tire Drag: 3%
If you have only 93.5% of the BTU value and you are not 100% efficient in the converting in the motor, etc , your output of energy is even lower in percentage compared to a gallon of gasoline.

Thus ethanol is lower in energy value. So why keep it...because it may be cheaper for a BTU of ethanol than a BTU of gas. I don't think this is the case yet since ethanol refineries are not as prevalent and therefore probably not as cheap yet. Also Ethanol plants have widely differing energy balances in the costs to produce ethanol.
They will get better as the use goes up.

I did read where the EPA finds the drop in MPG by 25% to 35% acceptable.

 

It seems to me if you are getting less milage per gallon, you are buying/burnining more gas to go the same distance. Oil companies might like that ($) but I think that is a step backward for the environment.

 

Of course, they have absolutely ZERO concern for the unwashed masses.

Have a great Thanksgiving!
Mike

 

Actually it may be worse than that. Everything I can find says E85 has 85% ethanol and 15% gasoline and an octane rating of 108 or so.

The thing I thought was curious about the original post and all the replies is that no mentioned 16.7 mpg. I average about 19 - 19.5 with mostly in town driving. Luckily I don't have a lot of wait time sitting in traffic and that may be the difference. If the original poster doesn't spend a lot of time sitting in traffic, there may be something other at work besides fuel mix.

Charlie

 

I use shell all the time. Don't notice any sulphur smell, but to be honest I never asked the people sniffing my exhaust if they noticed it either.



I average about 21-22 mile per gallon on my fuel info (dic) and confirm it by dividing the # of gallons by miles just to check it, and it's usually very close. And I usually drive very agressively, not for mileage!

Whoever said Top Tier fuels is just advertising, is wrong imo. Those cheap A$$ fuels at the quickie mart and BJ's lack additives that keep injectors clean etc. Id rather pay a few cents per gallon now than buy new injectors when they clog. But to each his own.

 

The poor 16.7 avg mpg is a direct result of an LPE installed Maggie, a ECS installed roller cam which really kicks Royal A__, A 3.1 pulley, ECS Alky, 373 gears and a big fat size 11.6 leaded right foot that is sometimes works too quickly. and some other stuff...........

 

PS...It still gets better mpg than my wifes 07 Equinox, my Chevy Blazer and most other cars on the road.

 

AHA!

Charlie