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Looking at the inside cover of the gas cap, it says that minimum octane is 91. With mid-grade being 87 and supreme being 93, would I be doing any good mixing the two grades? I know the octane only refers to how much compression the mixture can take, thus releasing more energy, but would the different octanes mix or separate like water?
 

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Re: Octane Mixture

The octane rating in gasoline refers to the amout of the straight chain hydrocarbon octane (C8H18) in the gasoline. The more octane in the gasoline, the more thorough the combustion. Octane also adds stability, making it able to take more compression without the risk of detonation.

The reason it says 91 minimum is because different parts of the country have different octane levels. Where on the east coast mid-grade might be 89, on the west coast, mid-grade might be 91. I've seen premium as both 93 and 95 before. It all depends on the refinery the gasoline comes from.

Edit: To answer your question, the only things you'd accomplish by mixing is wasting your time and making two transactions at the pump for one tank of gas...
 

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Re: Octane Mixture

MaoistBanker said:
...but I'd love to see the faces of onlookers as you put one pump in, took it out, and put another pump in.
...And you shake it all about.

MaoistBanker said:
Or would so try to stick both in there at once, like a porno?
It'd be even better if he pulled the nozzle out and sprayed it all over the hood when he was done.
 

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Re: Octane Mixture

DrJones said:
The octane rating in gasoline refers to the amout of the straight chain hydrocarbon octane (C8H18) in the gasoline. The more octane in the gasoline, the more thorough the combustion. Octane also adds stability, making it able to take more compression without the risk of detonation.

The reason it says 91 minimum is because different parts of the country have different octane levels. Where on the east coast mid-grade might be 89, on the west coast, mid-grade might be 91. I've seen premium as both 93 and 95 before. It all depends on the refinery the gasoline comes from.

Edit: To answer your question, the only things you'd accomplish by mixing is wasting your time and making two transactions at the pump for one tank of gas...
Well, that answers that. Thanks for the info. It might really be worth it if the gas station is crowded and after putting back the first nozzle, I held out my hand like "you aint seen nothin' yet" and reached for the other nozzle. "WTF is that guy doing?"
 

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Re: Octane Mixture

You cannot pump your own gas and most of the time there are parts where you cannot make left turns. Its weird i guess but i dont have any prob with it cause ill make lefts when i need to so noone is really stopping me. Other than a cop. My fast tells me what to do so i trust him with his decisions.
 

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Re: Octane Mixture

They've got that stupid law about pumping gas in Oregon, too. You had better not be in a hurry trying to gas up a rental car to make a flight, because the guys hired to fill the tank don't exactly haul ass to help you. Is it some kind of welfare state thing?
 

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Re: Octane Mixture

dean said:
They've got that stupid law about pumping gas in Oregon, too. You had better not be in a hurry trying to gas up a rental car to make a flight, because the guys hired to fill the tank don't exactly haul ass to help you. Is it some kind of welfare state thing?
Amen to that...

rr
 

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Re: Octane Mixture

Probably a gas jockey union thing. They don't want us "do-it-yourselfers" taking their highly skilled jobs away.

Is the left turn thing like in New Orleans, where you have to first take a right, then do a U-turn every time? That's fucking retarded.

My gas hatch thing says I should use 95, but I think that's European grade gasoline and that's different there. I recall octane levels there all being in the 90s and going as high as 98. I don't think it's equivalent to North American octane ratings though.
 

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Re: Octane Mixture

Wikipedia's results on "Filling Stations" yielded this:

All stations in New Jersey and Oregon, however, are mini service; attendants are required to pump gas because customers are explicitly barred by statutes in both states from pumping their own gas. Both states prohibited self service in the 1940s due to fears that foolish customers would handle gasoline improperly. Oregon's Department of Environmental Quality has also ordered a ban on self-service gasoline due to inexperienced pumpers being a significant source of groundwater and air pollution. Oregon's state fire marshal has also ordered a ban on self-service gasoline. Today, these states enforce the law because of the rapid increase of drive-offs, where people fill up their car and drive away without paying for gas. In 1982, Oregon voters rejected a ballot measure sponsored by the service station owners, which would have legalized self-service gas.
I think, at least in Oregon's case, this may be a pretext. They have such draconian laws regarding anything having to do with water (in order to protect their salmon supply) to the extent that a PUDDLE is considered a "potential salmon habitat." Can't have a bunch of drunk guys having gasoline fights at the 7-11. Some of the runoff might find its way into a crack in the sidewalk a salmon has his eye on.
 

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Re: Octane Mixture

Thalo said:
My gas hatch thing says I should use 95, but I think that's European grade gasoline and that's different there. I recall octane levels there all being in the 90s and going as high as 98. I don't think it's equivalent to North American octane ratings though.
This, again, from Wiki:

Fuels in the U.S. are described in terms of their "pump octane", which is the average of their "RON" (Research Octane Number) and "MON" (Motor Octane Number). Labels on gasoline pumps in the U.S. typically describe this as the "(R+M)/2 Method".

Some nations describe fuels according to the traditional RON or MON ratings, so octane ratings cannot always be compared with the equivalent U.S. rating by the "(R+M)/2 method".

In Europe, petrol is unleaded and available in 95 (Eurosuper) and 98 (Super Plus) octanes; in some countries, 91 octane petrol is offered as well. Some stations offer 98 RON with lead substitute.
 

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Re: Octane Mixture

So what's it like when someone who's lived their life in Oregon accidentally pulls into a self-serve only station in Washington? Would they even know what to do? Those laws in OR and NJ are retarded and I'm sure some kind of labor group must be behind it (just using other reasons like salmons and drive-offs to justify it).
 

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Re: Octane Mixture

tikiman said:
MINE SAYS 91 BUT IVE ONLY USED 93...THE SALESMAN SAID THAT I COULD USE 89 AND IT WOULD ONLY HURT THE PERORMANCE, HE SAID THAT THE CAR WILL "DETUNE" SOMEHOW BY ITSELF
Correct, You won't hurt your engine by running 89. You'll just hurt your performance. Every once and a while though I would run 93 through it.

For the record I have only pumped 93 so far. But then again I have only filled up a couple times so I have no idea what kind of performance loss you would have. Most people probably won't notice the 10-15 hp loss running a lower octane.
 

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Re: Octane Mixture

Thalo said:
So what's it like when someone who's lived their life in Oregon accidentally pulls into a self-serve only station in Washington? Would they even know what to do? Those laws in OR and NJ are retarded and I'm sure some kind of labor group must be behind it (just using other reasons like salmons and drive-offs to justify it).
I can't speak to the NJ folks, but I know in OR the salmon thing might be legit. Building codes and just about every other law requires permits of all kinds and certifications that the precious salmon won't possibly be harmed.
 

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Re: Octane Mixture

so I did a small experiment on my GTi... I filled up at my course with our regular 89 to see if I could feel a difference (and in no way am I a race car driver) the only time I felt a change in power was right after take off when the turbo is just starting to build pressure, but it wasnt dramatic I had to do it a couple of times to make sure. I also felt no difference on the freeway I could still pass cars with ease while in 6th..
my conclusion being for me at least is that 89 is ok in a pinch but there is always the thought in my mind of detination from the pressure being to high so, there for my Fast will always drink the good stuff.
 
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