Is it possible for me to work out how much petrol i would use driving for 2 hours on

kb36

I am aware that it is not 'very' accurate and that was why I stated a 'rough estimate' When I work out my trips it's always worked out to be a few quid either side for me of the estimate shown so does still serve a purpose - for me anyway.

AdrianHi

kb36 wrote: »

I am aware that it is not 'very' accurate and that was why I stated a 'rough estimate' When I work out my trips it's always worked out to be a few quid either side for me of the estimate shown so does still serve a purpose - for me anyway.

OK, I'm saying this out of academic interest, not trying to wind anyone up.
This is real world, I've done this:
Take 2 cars, one 47mpg official combined figure, one 50mpg official combined figure, both 2.0L diesel engines, 136bhp and 163bhp respectively (meaning effective cubic capacity could be who knows what above 2.0L.
Drive both cars on a 600 mile round trip from the south of England to Glasgow and back driving at the same time (in convoy) , same speeds, same stops, no dodgy slip streaming going on. The 136bhp diesel used approximately 40% more fuel than the 163bhp diesel, a difference of say £30 on the trip.
It's a bit more than a "few quid" out

Bobsworlduk

AdrianHi wrote: »

OK, I'm saying this out of academic interest, not trying to wind anyone up.
This is real world, I've done this:
Take 2 cars, one 47mpg official combined figure, one 50mpg official combined figure, both 2.0L diesel engines, 136bhp and 163bhp respectively (meaning effective cubic capacity could be who knows what above 2.0L.
Drive both cars on a 600 mile round trip from the south of England to Glasgow and back driving at the same time (in convoy) , same speeds, same stops, no dodgy slip streaming going on. The 136bhp diesel used approximately 40% more fuel than the 163bhp diesel, a difference of say £30 on the trip.
It's a bit more than a "few quid" out

You've got my brain ticking a bit now lol. I've been looking at a few Audi A4's 98-00 Its definitely a diesel I'm after.

They come in a couple of sizes a 1.9tdi (110 BHP) and a 2.5tdi (150 BHP) The quoted MPG's are 53 and 42 respectively.Most of my miles are done on the motorway around 70 - 80 :rolleyes:. So by the above reckoning could I be better off going for the 2.5 even though the quoted mpg is 11 less?

AdrianHi

Bobsworlduk wrote: »

You've got my brain ticking a bit now lol. I've been looking at a few Audi A4's 98-00 Its definitely a diesel I'm after.

They come in a couple of sizes a 1.9tdi (110 BHP) and a 2.5tdi (150 BHP) The quoted MPG's are 53 and 42 respectively.Most of my miles are done on the motorway around 70 - 80 :rolleyes:. So by the above reckoning could I be better off going for the 2.5 even though the quoted mpg is 11 less?

Tricky, depends as much on the car, aerodynamics, gearing as just bhp.
What I do know is the 2.5TDi is an older diesel engine suffering from very nasty lag, no go at all up to around 2000rpm then it suddenly takes off, more desperate when coupled to an auto box.
How about thinking a bit more laterally and getting the 1.9TDi 115bhp which is the better engine and then doing what is much more sensible (when you understand all the issues) than you might think, and getting it performance tuned (re-mapped) where it will then get up to about 150bhp. Unless you drive foot to the floor all the time, these re-designed maps also commonly improve fuel consumption by around 7% with possibly even better improvements for mostly motorway driving.