Actually, ethanol has a higher octane rating than (most) gasoline--that's why
it's used in some dragsters--but indeed has lower specific energy (i.e. BTU per
unit volume) so you get a decrease in mileage. I can get 93 and 100 octane gas
locally--but it's expensive--and the 100 octane contains ethanol whereas the 93
octane does not.
The reduction in available octane ratings seems to just be a trend; more and
more cars are built to run on regular and even most high-performance engines
only need 91 octane gas. In high elevation areas, it's hard to find anything
over 89 octane.
Bob
Ken Taplin wrote:
> Probably something to do with the addition of 10% ethanol last Nov.
> Everyone I know has also experienced at least a 10% reduction in gas
> milage.
> ----- Original Message ----- From: "Alex" <alexmm@roadrunner.com>
> To: <healeys@autox.team.net>
> Sent: Monday, May 18, 2009 9:29 PM
> Subject: [Healeys] Octane recession
>
>
>> I've noticed that all the gas stations locally here in southern Maine
>> have
>> reduced their high-test/premium product from last year's 93 octane
>> rating to
>> a 91 rating. Has anyone else noticed this downward change?
>>
>> == Alex in Maine
>> "The Blue Mainie," 1960 Austin Healey 3000 BT7
>> "Conkling," 1946 MG TC #1321
>> Former owner 1957 A-H 100-6, 1967 A-H BJ8,
>> 1965 MG Midget
>> http://home.roadrunner.com/~alexmm
>>
>>
*******************************************************************
Bob Spidell San Jose, CA bspidell@comcast.net
*******************************************************************
_______________________________________________
Support Team.Net http://www.team.net/donate.html
Healeys@autox.team.net
http://autox.team.net/mailman/listinfo/healeys
http://www.team.net/archive
|