rationale for some states limiting the octane of premium fuel?

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Pennsylbammyvania
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Is there any actual functional reason (claimed environmental, or otherwise) for certain states limiting the upper number (91 vs. 93) of the premium fuels sold there? shrug I do NOT want this thread to turn to verboten topics, at all, with some insisting on inserting their particular worldviews into it, and will request that the mods delete it if it does!! wink Just looking for some answers on why this is so, that's all. wink
 
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Higher octane levels are not needed at high elevations. Due to lower oxygen content/combustion. That is something I read many years ago. I did not index the internet. Just from memory. But, there are much better scientific minds on this forum.
 
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Buffalo, NY
^^+1 Yeah, it's more about elevation than any EPA policies:
Quote
Squeezed Q: I live in Arizona and use 87-octane regular. In Utah, Idaho and Nevada, stations were selling 85-octane as regular gas. This forced me to pay more for midgrade 87-octane. Is this the latest petroleum-industry scam to get more of our money? Will my car run okay on this bogus 85-octane regular? A: Octane is the ability of a fuel to resist knock, and high-compression engines tend to knock more. The obverse of that is that lower-compression engines can run on lower-octane gas. Air is thinner the higher above sea level you go. Less air going into the cylinders means less pressure at top dead center when things go bang. It's a lot like lowering the compression ratio in the engine, reducing the need for high octane. Cars will run just fine on lower-octane fuel when they're well above sea level--and all of those states are. Hopefully, by the time you get back down to denser air, you've burned off most of the low-octane stuff, and can refill the tank with higher-grade fuel.
https://www.popularmechanics.com/cars/how-to/a5308/4345737/
 
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I don't think it's actual state law limiting available octane in high altitudes. Rather, it is not always needed due to the thinner air, so gas stations and their customers won't spend the extra money on 93 over 91. However, with regular, the cars that don't require premium, many recent cars now require 87 regardless of altitude since modern engine management can compensate for the thinner air. The only non-high-altitude state I know of that doesn't have 93 available is California, and that is due to their strict environmental standards in regards to emissions. The cheapest ways to make California-compliant 93-octane are under patents held by a company that went out of business.
 
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Could be related to emissions at the point of fuel production.(the 'cracking tower' at the refinery. No idea that burning 93 octane is any dirtier than burning 87. Catalysts should be able to scrub both really clean.
 
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Illinois
This is what I was thinking. I don't think the STATE is limiting it. It is more likely a choice by those who sell fuel. If you are at a higher elevation, you MAY not need the higher octane fuel.
Originally Posted by slacktide_bitog
I don't think it's actual state law limiting available octane in high altitudes. Rather, it is not always needed due to the thinner air, so gas stations and their customers won't spend the extra money on 93 over 91. However, with regular, the cars that don't require premium, many recent cars now require 87 regardless of altitude since modern engine management can compensate for the thinner air. The only non-high-altitude state I know of that doesn't have 93 available is California, and that is due to their strict environmental standards in regards to emissions. The cheapest ways to make California-compliant 93-octane are under patents held by a company that went out of business.
 
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San Antonio, TX
Originally Posted by slacktide_bitog
I don't think it's actual state law limiting available octane in high altitudes. Rather, it is not always needed due to the thinner air, so gas stations and their customers won't spend the extra money on 93 over 91. However, with regular, the cars that don't require premium, many recent cars now require 87 regardless of altitude since modern engine management can compensate for the thinner air. The only non-high-altitude state I know of that doesn't have 93 available is California, and that is due to their strict environmental standards in regards to emissions. The cheapest ways to make California-compliant 93-octane are under patents held by a company that went out of business.
Does that mean that 93 octane doesn't burn clean enough for California? I wonder how octane is related to emissions.
 
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Apparently it has to do with devoting crude to production of more mid-grade gasoline. Thereby stretching reserves. Check Slate.com about : Is premium premium?
 
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southeast texas
Kinder Morgan sent out a questionnaire requesting input, and the consensus was 91 octane. Essentially all of the gasoline could be transported thru their pipeline.
 
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Originally Posted by das_peikko
Originally Posted by slacktide_bitog
The only non-high-altitude state I know of that doesn't have 93 available is California, and that is due to their strict environmental standards in regards to emissions. The cheapest ways to make California-compliant 93-octane are under patents held by a company that went out of business.
Does that mean that 93 octane doesn't burn clean enough for California? I wonder how octane is related to emissions.
It's not directly related. But there are multiple ways to create a higher apparent octane rating and some of them are unacceptable to California, if what people are saying is correct.
 
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Regina, Saskatchewan, Canada
Originally Posted by Nickdfresh
^^+1 Yeah, it's more about elevation than any EPA policies:
That's what I thought. Of course, we're not the States, but some provinces have much better availability of 93 octane than others. This province only has one brand that sells it, and the rest sell 91. Of course, it's still available and legal; it's just rare.
 
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