I posted this in a different thread about engine stalls but it seems more appropriate here.
I contacted Chevron about why I can only find 91 octane in California and this was their response. Seems there's a pipeline supplier to 'western states' that limits the anti knock index (octane) in their gas to only 91.
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Dominic,
Your inquiry was forwarded to us here at ChevronTexaco Fuels Technical Service.
We are sorry to say Chevron does not market 93 or higher octane gasoline at Chevron stations anywhere in the United States. It is more likely that you will find the octane of 91-93 to be the highest available in most places, even by our competitors. To our knowledge, most all car manuals do not recommend the need for anything higher than 91.
There has been a reduction in the Antiknock Index (AKI) (also commonly known as "octane" - the number posted on the dispenser pumps at the service stations) in the Supreme (Premium) grade of Chevron gasolines. This likely has been the case in most all other brands of premium grade gasolines marketed in California and most of the Western states. This reduction took effect August 1, 2001. At this time we do not know whether non-Chevron 93 or 92-octane gasoline may be available in certain areas of these states.
Chevron converted to 91 octane for Supreme gasoline in response to changing pipeline specifications in these Western states. While Chevron was not in favor of reducing the octane of Supreme, complying with this change allows for the continued efficient and reliable distribution of gasoline to consumers. Specifically, Kinder Morgan Pipeline Company notified Chevron that effective August 2001, minimum octane specifications for Supreme grade gasoline shipped for sale in these states would be 91 octane. Those pipelines are important to Chevron - and we believe to others - in ensuring a reliable supply of gasoline to consumers.
Some UNOCAL station in California sell 100 Octane (AKI) racing unleaded gasoline.
There are specialty racing fuels (with higher octanes) available through independent companies.
For racing fuels, try these resources:
ERC Engine Research Co.
San Lorenzo, CA
(510) 276-9334
Tech Line: (800) 445-1479
Chevron Phillips Chemical Co.
Phillips Racing Fuels
Racing and Reference Fuels website address:
http://www.p66race.com/
Telephone (Toll Free)
1-888-P66-RACE