<snip>
>This is not always true. I saw a review of the new Infiniti SUV on Motor
>Trend TV. Infiniti designed the SUV to run on low grade fuel (either 87 or
>89 don't remember which). They specifically said not to use premium fuel.
>The point is that engines are designed to use a certain grade fuel. If the
>manual says use a minimum grade of 87 or 89, then it can be assumed that it
>is okay to use a higher grade. However, if the manual states a specific
>grade without denoting it as a minimum, then you can't assume it is a
>minimum recommendation.
>Andy
<snip>
Unless those automotive courses I took (not to mention the several years of
working on race cars) were wrong, Octane is a measure of the amount of
anti-knock agents that are added to gasoline. It is difficult to get the
(RON+MON)/2 number greater than 100 without adding lead (or alcohol), which is
one of the reasons that (big) engines back in the 60's usually had higher
compression ratios than those of today. Basically then, there is no reason to
use an octane greater than the manufacturers recomended value unless you use
your engine in a way not intended by the manufacturer. Cars with high
effective compression ratios usually need higher octane gasoline (thus the
need for 93+ octane in supercharged/ turbocharged vehicles).
I cannot see any reason that adding "Premium" gas will hurt anything (except
when companies like Mobil put additives into their premium gas for Fuel
Injector cleansing purposes).
On a side note, my '98 dakota 318 has a CC recomended octane rating of 89,
which is different than 97 and earlier vehicles.
Just my $.02 worth.
Geoffrey Hausheer
Intel Corp.
Hillsboro, OR
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:07:55 EDT