We have the same effect with our Saturn. Premium gas yields better
mileage. In the case of the Saturn, I was able to nail it down to the
engine management electronics by experimenting with a timing light and
talking to a Saturn mechanic.
The premium gas doesn't "ping" as easily, which keeps the preignition
sensor happy, which allows the electronics to run more ignition advance,
hence more efficiency and gas mileage.
I sat down and figured out that the "mid-grade" gas got us the most
"miles per $", at least until the recent price craziness.
Chris K.
> Date: Wed, 5 Jul 2000 10:32:24 -0600 (MDT)
> From: "Andrew B. Lundgren" <Lundgren@iname.com>
> Subject: Re: Octane and altitude ratios???
>
> That damage to the pocket book is what I am trying to avoid. I have a Ford
>Explorer as
> well as an MGB that gets 15-16mpg... The owners manual says 87 or higher,
>but I think
> that is calcualted for sea-level. When I buy the highest available octain I
>get better
> gas mileage... This is just one of lives mysteries I wanted to understand
>better.
|