Rang Rover Sport MPG ?

[screem]

I have been driving the RR Sport Supercharged for over three months now and probably do a 50 50 split of motorway and city driving.

The published consumption figures are this

Fuel consumption (urban) 12.4 mpg
Fuel consumption (extra urban) 23.7 mpg
Fuel consumption (combined) 17.8 mpg

I have been trying my best now to get the MPG that is shown on the trip computer to show the best mpg but ive only managed to get it to show 14.4mpg !

Ive not reset it for over three months.

Im sure i could get it higher by resetting it while travelling at 56mph but I think this is cheating.

With petrol at an all time high Im beginning to think I should have bought the TDV8

So if anyone else has a TDV8 or supercharged please tell me what does your trip computer show? and how long since you last reset it?

one last question: Although 56 mph is often referred to as an ideal speed for high mpg, is it the best speed for economy in a 4.2supercharged?

[tomw2000]

Not driven a SC Sport. But we have a TDV8 diesel one (2009/58plate) and in the nearly 29,000 miles we've done in it in just over a year, the long term MPG average is 25.

The wife uses it ainly for work and does long journeys (hence the big miles).

[andyb66]

screem said:

one last question: Although 56 mph is often referred to as an ideal speed for high mpg, is it the best speed for economy in a 4.2supercharged?

The 56 mph is a 'hang over' from the US where the motorist of the 50s and 60s wanted to know the MPG for 'freeway crusing'.

Best MPG is probably achieve when the engine revs are at the point of maximum torque. Altho' driving style will have an effect too

[Jem0911]

My 4.4 gets me 16.4MPG from the OBC.

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tomw2000 said:

Not driven a SC Sport. But we have a TDV8 diesel one (2009/58plate) and in the nearly 29,000 miles we've done in it in just over a year, the long term MPG average is 25.

The wife uses it ainly for work and does long journeys (hence the big miles).

Out of interest what is the average speed saying?

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andyb66 said:

Best MPG is probably achieve when the engine revs are at the point of maximum torque.

I thought maximum torque was achieved at minimum revs, ie the lower the revs the higher the torque?

If you are correct that the best fuel consumption is at the point where the torque is greatest then on this basis i guess that would mean that the most effective speed for low consumption of fuel would be the point that the auto box just changes into top gear ie the lowest revs for the highest gear?

Or is my thinking out here?

Im gonna post this very question in General gassing!

[tomw2000]

screem said:

tomw2000 said:

Not driven a SC Sport. But we have a TDV8 diesel one (2009/58plate) and in the nearly 29,000 miles we've done in it in just over a year, the long term MPG average is 25.

The wife uses it ainly for work and does long journeys (hence the big miles).

Out of interest what is the average speed saying?

I'll check that for you. Although I think Main dealer reset everything last week when they did some suspension recall thingy.

I'll have a look and let you know.

[tomw2000]

Update: Main dealer had reset the OBC, but prior to that the wife's longterm ave. mpg was deffo 25 (i'd never really kept an eye on the ave.speed before).

I just checked it now - mpg was 24.2 and ave. speed was 37.2.

To be fair most cars I have (when I have bothered to keep an eye on it) have an ave speed of between 30-40.

Mind you, I did do a 1hr plus spin in the 911 the other week and managed to average nearly 70mph.
Just very lucky because there was hardly any traffc around to hold me up

[andyb66]

screem said:

I thought maximum torque was achieved at minimum revs, ie the lower the revs the higher the torque?

There is a torque 'peak' somewhere in the rev range, in my TDi Discovery this is about 2000 rpm.

I agree with you, however, that best MPG is likely to be the road speed just after the TC has locked up (or as you put it the autobox has gone into top gear).

[poj]

I have a TDV8(56 plate,72,000 miles)it does 21.4MPG.

[Tff]

I tried really hard the other day, and on a two day average I got 30mpg from my 07 TDV8! Usually 25ish

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Tff said:

I tried really hard the other day, and on a two day average I got 30mpg from my 07 TDV8! Usually 25ish

That sounds about right. The figures for the TDV8 as advertised are:

Fuel consumption (urban) 19.3 mpg
Fuel consumption (extra urban) 31.4 mpg
Fuel consumption (combined) 25.5 mpg

Its just frustrating that the TDV8 figures appear to be achievable but the SC are impossible to get near?

Is anyone out there with a SC getting anywhere near the advertised consumption figures?

[RRS_Staffs]

TDV8

30mpg on the motorway at 75-80 ish

20mpg round town

[ilaishley]

My lifetime average (57 TDV8) is 24mpg. Long trip down to the alps and back gave me 27mpg

Ian