Elmo P. Shagnasty wrote:
> In article <1jfl1zo9zf0s1.dlg@ss.me-privacy-net.com>,
> "S.S." <me@privacy.net> wrote:
>
>
>>Just use the "Regular 87". Using higher octanes won't harm the engine, but
>>it will definitely harm your wallet.
>
>
> Higher octane fuel, in fact, will lead to *less* gas mileage for that
> car.
>
not necessarily. depends how smart the engine management system is. in
the "old" days before knock sensors and crank angular velocity
measurement, igniton timing had a fixed map. with the above sensors,
you have a base map, but also an algorithm that monitors these two other
factors and from that, it can calculate in real time a set of new
ignition characteristics to take maximum advantage of any particular
fuel. i would hope that the expensive "super econo" car's management
would be this smart.