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Discussion Starter · #1 ·
I'm kind of confused, If California is so "emissions conscious" then why is the highest octane rating that you can get there 91? I was always under the impression that the higher the octane rating, the cleaner the emissions. BP also advertises this fact about their 93 octane fuel on our local radio stations. Does California fuel have other additives that clean up the emissions of the 91 octane? Can't they do the same thing with 93 or 94 octane? Please enlighten me.
 

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i do not think octane has much to do with emmisions, just additives. the only emmision related octane issue is the old use of lead to boost octane. ocatne is really a measure of the combustion properties. from what i have gathered.
 

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I agree, higher octane only increases performance not decrease emmisions. California gas has some additives to it too. Guess that's why it's more expensive here than in any other state. I also wondered if higher octane gives you better gas milage. I get 26mpg in combined driving, wonder what I'll get with 93 or 94.
 

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O-wood said:
I agree, higher octane only increases performance not decrease emmisions. California gas has some additives to it too. Guess that's why it's more expensive here than in any other state. I also wondered if higher octane gives you better gas milage. I get 26mpg in combined driving, wonder what I'll get with 93 or 94.
Generally speaking you'll get slightly higher mileage with higher octanes, but it's hardly worth the extra cost.
 

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Discussion Starter · #5 ·
O-wood said:
I agree, higher octane only increases performance not decrease emmisions.
This conflicts with what BP (British Petroleum) advertises. They claim higher octane fuel reduces harmful emissions, that's the reason I'm questioning why CA only uses 91 octane.
 

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we dont have BP in california..plus its like "the tornado" claiming to increase hp by 25...
 

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Higher octane itself does not increase performance. Higher octane gasoline is actually less combustible than lower octane gasoline, so think about it...

It simply allows you to tune your car to a state where it can produce more power without detonation (unintentional ignition). In some cases, stock EMS' may be able to capitalize (to a point) on higher octane when utilized.

There was a great article on the 'net somewhere that blew all the myths regarding octane = HP.

-Pace
 

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Flyboy said:


This conflicts with what BP (British Petroleum) advertises. They claim higher octane fuel reduces harmful emissions, that's the reason I'm questioning why CA only uses 91 octane.
that's because BP is lying. higher octane does not reduce emissions--in fact, if you engine is not tuned to work at higher octane ratings, you could be polluting more.

WHAT IF I PREFER TO USE GASOLINE WITH HIGHER OCTANE RATINGS?

You can, but there are no real benefits, other than the gasoline manufacturers making more money off of you. When you use a fuel with a higher octane rating than your vehicle requires, you can send this unburned fuel into the emissions system. It can also collect in the catalytic converter. When you over stress any system, it can malfunction or not do what it was designed to do properly. In the early 90's, an early warning symptom was a rotten egg smell from the tailpipe. Easy fix, go back to using regular 87 octane gasoline. The rude odor usually disappears after several tanks of gasoline.
the reason why california pumps only sell premium gas at 91 is because the state is geared to ban MTBE as a fuel additive. MTBE was added to fuel to fully oxygenate combustion of gasoline, reducing NOx emission. it also had the side effect of boosting octane rating. but it was found to comtaminate ground water tables all over the state, so the state is switching to ethanol blend. it is more expensive and companies are only permitted to put half as much EtOH at MTBE, so they will not be able to boost octane as high. they could use alkaloids to boost octance, but they are more expensive. so before 2003 when MTBE is out and EtOH is in, they are lowering their MTBE-blended gas to 91 octane.

http://www.ocregister.com/business/features/2000/power/octane00727cci2.shtml

so, learn the facts before you go off half-cocked ranting about california, dumb-ass.


***You answer someone's question only to call them stupid? Think about that for a minute. -dR ***
 

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All octane tells you is the fuel's resistance to detonation. How much compression ratio (or boost) it can handle without knocking.
 

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Discussion Starter · #11 · (Edited)
yodayoda said:
so, learn the facts before you go off half-cocked ranting about california, dumb-ass.
Was that directed toward me? I have been a member of this forum for the past 6 months and have always contributed in a positive manner, I'm sure all of the moderators will verify this. However, your "dumb ass" comment was not at all necessary. How do you interpret my post as "half-cocked" or "ranting"? My opening sentence was, "I am confused", and I was looking for some clarification from California residents regarding this topic, not to be called a dumb ass. I am a 31 year old man who is a management employee in a Verizon call center that employs 1100 people. I am also an FAA certified flight instructor with a Bachelor's degree in Aviation Management, hence the name "Flyboy". Sorry to read you all my resume but I think this qualifies me as not a dumb ass.

I think that an apology is definitely in order, Dumb ass!
 

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I thought Flyboy's post consisted of a very straightforward question. There was no rant, and there was no propagation of misinformation.

Which is why I asked yodayoda to play nicely.

-Pace
 

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yodayoda said:



so, learn the facts before you go off half-cocked ranting about california, dumb-ass.

Why do you think he asked the question............TO LEARN THE FACTS!!!!!! Maybe you should ask an adult to proof read your post before you click on the submit reply button.:rolleyes:
 
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