In article <i_WdnbHfUslmVCPfRVn-jA@speakeasy.net>,
jim beam <nospam@example.net> wrote:

> > 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.

No, it has no need to do any such thing. It is designed to operate on
86 octane fuel. It has no need to "take advantage" of anything else.