93 Octane or 87 Octane?

We have several stations here in Oshkosh that sell ethanol free fuel. Only about 5 cents more per gallon.
 
As flatjack sees it differently, I thought I'd paste this link:
https://www.fuelfreedom.org/what-is-octane/

To achieve the octane rating Tetra ethyl lead was added to the fuel. It is nasty stuff. This is the lead that was removed from the fuel. It had the benefit of lubricating the valves and seats. I don't know what additive is used these days to achieve the required "octane rating", but nowadays (generally speaking) hardened valve seats are required where they may have never had them. (off topic)
 
"Actually octane is a hydrocarbon that is blended into fuel to prevent it from auto igniting. It's use maintains an orderly flame front across the combustion chamber. The octane rating is used to rate the performance of the particular fuel being used."

An iso-octane mixture is made in many refineries in a unit called an Alkylation unit. BTW an octane rating is a measure of the resistance of gasoline to ignition. The higher the octane rating the more resistant to ignition. The unknown sample is compared to a mixture of iso-octane with a rating of 100 and n-heptane with a rating of 0.
 
JSeery said:
Kube it is becoming more common in larger cities. Used in lawn equipment etc.
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The small engine manufacturers and marine industry really pushed on EPA to allow alcohol-free, and it seems to have borne fruit.

When I drove thru Iowa a while ago (heart of cornbelt and many ethanol plants), I was confused by there being two 89 octane choices, one that cost 25 -30 cents more. It was not identified as non-alcohol, so I asked the clerks. None of them could tell me the difference. On my way out, a local told me that the higher-priced stuff was indeed alcohol-free.
 
Now I'd like to hear or read a good explanation why ethanol free would be more expensive.
The process involved in making ethanol has got to be
none cost effective.
 
RobR'35 said:
Now I'd like to hear or read a good explanation why ethanol free would be more expensive.
The process involved in making ethanol has got to be
none cost effective.
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Dedicated trucks for delivery, low volume, separate tanks at the refinery....
 
In my area the Kwik Trip gas stations have a separate pump for Recreational Gas that has no ethanol.
 
Yoy might want to remember the lower the octane, the more BYU's of heat per pound of fuel. Therefore, you get better mileage with the lowest fuel your engine can run on.However, engines with higher compression ratios need a better fuel. These engines are more efficient and therefore may get better fule mileage. Combustion chambers also have Octane numbers. Thats why I like to have a tight chamber, this improve turbulence and allows a hier compression with a lower Octane fuel. Kinda like chasing your tail
 
RobR'35 said:
Well I'll say this Kube.
Most gas stations in and around where I live state that on there gas pumps 93 oct. 99 out of 100 times is ethanol free.
I truely believe it's not needed in our fuel.
I've spoke with guys that have worked on old cars longer than I've been living. They've said they've changed out more gas tanks on these old cars since the new use of ethanol in the fuel than ever before.
To me that says something. Fuel lines,rubber hoses,rubber diaphragm,fuel pump valves etc.
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Rob, I agree with you and I found out first hand the damage from 87. Because my 47 with the 59 AB was running with pump 87 for years (before I bought it), I've had to drop my tank and have it reconditioned. There was enough rusted flakes to fill a cereal box. Plus the fuel bowl was cloudy. I ripped out the old fuel lines, rebuilt my fuel pump and am crossing my fingers that my carb won't need to be rebuilt. I will only be running non-oxygenated fuel in my flathead once I get it running.

Also 87 octane goes bad after two weeks. I don't even use it in my Benz, or my 86 Laser Turbo.
 

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And then, I also grew up with gas and oil. We signed up with Atlantic Richfield that
went to Atlantic the ARCO. I think there were 3) 5,000 gal tanks. Being a curious
kid, don't you think I would see the truck driver flipping valves or something on the
tanker?? No he just stuck the hose in the next tank. Then comming into the 1960's
1970's the big thing was the so called sealer of weights and measures. He would fill
a glass jug to make sure the pump pumped an exact gal. Next stick test tubes in
the gas to check the grade if good he puts a sticker on the pump. This full service
gas station / shop is right across the street. I'm always over there I see no stickers
on pumps and yet to see delivery guy flipping any valves. Am I missing something?
It wouldn't surprise me one bit if you know what I'm thinking. Guess there are no more gas cops but pull in a weight station and they will stick test tubes in ya diesel...
 
Busting the myth: High octane gasoline is not necessarily more expensive than low octane gasoline, because the octane rating of a fuel can be manipulated in inexpensive ways, for example, the addition of water to fuel will raise the octane rating. Gasoline with ethanol added will have a higher octane rating because ethanol contains water, and attracts water, while gasoline does not. Therefore, buying fuel on the basis of its octane rating is merely an in dictation of how fast a fuel will burn, not how the octane rating was achieved.
 
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