On Fri, 21 Aug 2015 02:35:40 -0700, therustyone wrote:


The only time I've noticed a slightly smoother engine (though no
significant improvement in mpg) was when I accidently filled up with
premium diesel instead of standard diesel - and a lot of that may have
been wishful thinking to compensate for paying through the nose for the
"gold plated" fuel :-) I wouldn't have minded quite so much but I'd
driven past loads of garages on my journey, holding out for the
cheapest garage that I happened to pass, and then when I found a cheap
garage I went and used the premium holster instead of the standard one.
Shame they aren't different colours (eg black versus black with yellow
stripes, or something like that).

might depend on the car's sophistication. A quality engine will monitor
pinking and adjust the timing and fuel ratio to optimise burning with
the better quality (petrol anyway) it finds. An older car will just be
set to run on the worst fuel around.

There's no need for any fancy engine management gizmos to make a car
petroleum spirit agnostic as anyone who owned a 1970s Lada (eg my dear
departed Papa) would be able to tell you.

There was an under the bonnet octane rating adjustment. Basically it
amounted to a calibrated ignition advance/retard adjustment with a
vernier thumb screw.

--
Johnny B Good