7.4 litre car MPG

[Charles Morgan]

I saw a feature in the Telegraph on a London to Edinburgh bodied Rolls Royce Silver Ghost - here for those able to keep under the free article limit.

The reason for the name turns out to come from the bodywork of the car driven by Ernest Hives (an apprentice who became chairman) from London to Edinburgh in 1911, all the way in top gear, averaging over 24 mpg.

Fast forward 100 years and would a modern 7.4 litre car with 100 years of additional technology do much better?

 

[Sp!ke]

How many 7.4L engines only make 45 to 50 bhp though?

A 45 bhp engine in a modern ecobox on wheels would do close on 100mpg, if it could haul the weight of that thing I doubt it would get much less than 50mpg.

It could probably be calculated scientifically..queue Dieseman

 

[LTD]

Skinny tyres, bugger all rolling resistance and probably zero traffic enroute.

21 mph average.

With a bit of extended training, I could cycle that .....

 

[wemorgan]

Some modern large cc engines shut down the combustion for some cylinders. So the 7.4 litre may become ~2.5 litres. I'd guess at 60mpg it may give close to 40mpg.

 

[MOCAŠ]

Some modern large cc engines shut down the combustion for some cylinders. So the 7.4 litre may become ~2.5 litres. I'd guess at 60mph it may give close to 40mpg.

Mine does that, yet despite its only having 5.5 litres to start with, I have yet to see more than (an indicated) 25mpg.

 

[tim.100]

Mine does that, yet despite its only having 5.5 litres to start with, I have yet to see more than (an indicated) 25mpg.

I have driven a Chevy 454 (7.4l big block) in a late 80's pickup, for 4 hours, at American speed limits of 55mph.

We had to refill both 25 US gallon tanks in the truck before driving back home. Got back with a few quarts to spare!

 

[stereophoney]

I've got just over 34mpg average speed of 51mph over 200 miles in a CLK55. Was hard work though!

 

[MOCAŠ]

I've got just over 34mpg average speed of 51mph over 200 miles in a CLK55. Was hard work though!

Was that roof-up or down? I don't think my preference for open-top motoring helps the mpg figures at all.

 

[stereophoney]

Was that roof-up or down? I don't think my preference for open-top motoring helps the mpg figures at all.

Mines the coupe, so roof was very firmly up! Mostly on the M1, though did have to go on the M25. Cruise control set to 60mph, so a very boring drive!