My old series 3 was my daily driver for over 5 years - would cruise at 100 - 110kph but no more (would top out at about 125 downhill) - I used to average 17mpg - and it was no use having the radio on.
I had a recently reconditioned engine with a reconditioned head. The carby was fully reconditioned as was the dizzy that I had converted to electronic ignition. I had extractors on it as well. My car was running road tread narrow tyres with high tyre pressures - and FWH.
So speed is OK but fuel consumption is never going to be great.
A series 3 is not really the type of vehicle for what you use it for but ensuring everything is right does make it better.
Garry
REMLR 243
2007 Range Rover Sport TDV6
1977 FC 101
1976 Jaguar XJ12C
1973 Haflinger AP700
1971 Jaguar V12 E-Type Series 3 Roadster
1957 Series 1 88"
1957 Series 1 88" Station Wagon
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