Guy King wrote:
The message
from "vortex2" contains these words:


I'm nearly convinced. Is there any negative side to running higher octane
fuel in your engine?


It costs more! Not all engines are capable of making the best of higher
octane fuel - in fact, very few are.

Try asking in uk.rec.cars.maintenance instead.

Depends on the engine management software. My old Saab 9-3 LT gives 10%
improved consumption using "big name" brands like Esso or Shell compared
to the bottom of barrel stuff from Tesco, Asda and cut price
independents. So for paying 1-2% more there's a 5-fold return.
But on a car with a less tuned engine you probably wouldn't get much
difference.

john2