Dave Plowman (News) wrote:

It doesn't on my BMW 530 - or at least not enough to be certain. I've
done many London - Aberdeen journeys using the cruise where possible
on a full tank of 97/8 one way and 95 the other. And not had
conclusive results. In performance or economy. If it really did make
such a difference on specific models I'd expect Shell to use this in
adverts.

I had my S60 remapped for higher octane fuel - that's when you find the real
difference - extra 45bhp, about 5-10% better fuel cruising. Without the
remap there was no difference.

T5 models are mapped for 97 and run under par on 95.


--
The pellet with the poison's in the flagon with the dragon; the vessel
with the pestle has the brew that is true.