In article ,
The Natural Philosopher wrote:
Ah, in the glorious days of carburettors and five star petrol, my MGs
ran best on 5 star, and a damp cool misty day, and weer rough old dogs
on 4 star on a dry hot day.

No standard MG was ever designed for 5 Star. Early Rover V-8s were, though.

Rough running on a hot day was usually down to fuel evaporation and SU
pumps. Later cars had a constantly circulating fuel rail to help keep it
cool

BTW as the formula one crowd discovered some years back when they were
unrestricted on fuel, apart from it being '95 octane' or something,
there are any amount of aromatic hydrocarbons you can add that will net
you huge power increases in high comp engines, acting as flame
retarders, and huge extra MPG, by being super dense..the fuel may have
passed the test for '95 octane' but pump fuel it was not. Highly
corrosive, highly carcinogenic and very very nasty stuff..

--
*When cheese gets its picture taken, what does it say? *

Dave Plowman London SW
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