Making a more fuel efficient petrol Range Rover?

[dnb]

An intellectual excercise. (I won't be trying any of them unless they are really good!)

I budgetted for using my 2001 RR Vogue for 5k miles a year, but I found that I really enjoy driving it (me getting old?), so I have been leaving the Impreza in the garage more and more, so I wondered what can be done to improve fuel economy...

Currently it does 16.5 urban and 21.2 extra-urban according to the mpg gauge. So not far off book figures.

Current thoughts:

LPG conversion. Payback will be around £100 per 1k miles, and has the disadvantage of being a little more complicated than usual to get a good (OEM looking) install in a Thor RR.

Chevvy LSx engine conversion. Expensive, but more performance too (a good thing - 250 bhp isn't really enough ) TVRs with the conversion tend to do 10% to 20% better on fuel, so there's no reason why a RR shouldn't improve in a similar way is there? It would be possible to gas convert this too for even more savings, but I'd have to do a LOT of miles to make it pay.

Swap the current RR for a new v8 diesel RR. I don't even want to think about the depreciation on this one. It's probably going to cost more than the LS conversion!

Any more ideas? The crazier the better, as long as they are physically possible.

[ruaricoles]

dnb said:

Swap the current RR for a new v8 diesel RR.

It'd take a long time for that one to pay for itself in fuel savings alone....!

LPG has to be the way forward if you're intending to keep the car for long enough that it'd comfortably pay for itself.

You could get some tape out and cover up all the body shut lines (even the driver's door if you then climb in through the window). Or slightly more seriously, if you never do any towing or high load driving in hot countries you could ditch the viscous fan and fit an electric one which would probably give you some decent benefits.

Ruari

[Dick Fromage]

The answer is simple.

Sell the Impreza.

[eliot]

dnb said:

Chevvy LSx engine conversion.

Thats what they really need. I found my 4.6 too slow, ok admittedly I'm spoilt with the abundance of power available in the dakar - but an LS1 would give it a useful shove.
The main issue is integrating the electronics with the BECM.
I feel its an easier task with a GEMS as I think you can bin it and run aftermarket.
With the bosch ECU I think you would be better of trying to remap it to suit the chevy. I suppose you could cheat and fit 23% larger fuel injectors and hope the the ECU can learn around it.

[dnb]

I was talking to Mark Adams at the weekend. I think he may soon be able to do something with the Bosch system.

I agree with them being a little underpowered. The Thor engine is definitely torquier than the GEMS, but it's still not enough when I have just got out of the TVR.

Sell the Impreza? How would that help?

[Dick Fromage]

dnb said:

Sell the Impreza? How would that help?

Well, you gave me two clues. Firstly that it was an intellectual exercise and, secondly, that you had budgeted for £5k miles in the Range Rover.

This led me to believe that you had therefore made a similar calculation for using the Impreza and you also told me that you take the Range Rover far more than the Impreza (if at all?).

Ergo (always wanted to use that word!), if you dump the Impreza not only are you ridding yourself of a car that you are seldom using but also the Range Rover gets the Impreza's petrol budget.

QED.

[dnb]

The only two flaws in your plan are:

1. I'd look daft autotesting the Range Rover. (The TVR is not suitable for some venues I visit)
2. Every time I drive the Impreza I forget all about wanting to sell it.

[Dick Fromage]

dnb said:

The only two flaws in your plan are:

1. I'd look daft autotesting the Range Rover. (The TVR is not suitable for some venues I visit)
2. Every time I drive the Impreza I forget all about wanting to sell it.

Damn and blast! Foiled again!

What's autotesting then?

[Meeja]

Dick Fromage said:

What's autotesting then?

Cheap motorsport.

And great fun - although I have only ever watched rather than take part (lack of a suitable car!!!)

http://www.aswmc.org.uk/autotest.htm

http://www.youtube.com/watch?v=H3U7NktNj1o

[Dick Fromage]

Meeja said:

Dick Fromage said:

What's autotesting then?

Cheap motorsport.

And great fun - although I have only ever watched rather than take part (lack of a suitable car!!!)

http://www.aswmc.org.uk/autotest.htm

http://www.youtube.com/watch?v=H3U7NktNj1o

I bet Paul Swift could do it in a Range Rover!

[eliot]

dnb said:

I was talking to Mark Adams at the weekend. I think he may soon be able to do something with the Bosch system.

No doubt, but he will probably relieve you disproportionate amount of cash in relation to the value of the vehicle to do so.

[dnb]

They're appreciating at the moment. A like-for-like replacement for mine would be at least £1k more than I paid. And have you ever known me pay over the odds for anything?

BTW I am not convinced the BECM talks much with the engine ECU other than passing fault codes and diagnostic stuff around and receiving engine RPM.

Edited by dnb on Saturday 8th August 23:04

[Triple7]

Surely this talk of redcing fuel costs is a false economy? I reckon 18MPG out of a RR is about a good average. So by tweaking or LPG-ing what sort of figures are you going to get instead, 23-25MPG? Big deal, a whaopping extra 5 or 10 miles per gallon. I think it is far cheaper just to leave as is and pay the extra on petrol costs. Then to even think it'll be cheaper for you to trade it in against buying a TDV8 RR you must be nuts!

[eliot]

My P38 pulled around 12mpg around town and about 16 on a motorway at 70mph.

[GreenV8S]

If you take an angle grinder to the upper bodywork and fit aeroscreens you could probably improve the fuel economy considerably. You might need quite a big tonneau cover though.

[dnb]

Triple7 said:

Surely this talk of redcing fuel costs is a false economy? I reckon 18MPG out of a RR is about a good average. So by tweaking or LPG-ing what sort of figures are you going to get instead, 23-25MPG? Big deal, a whaopping extra 5 or 10 miles per gallon. I think it is far cheaper just to leave as is and pay the extra on petrol costs. Then to even think it'll be cheaper for you to trade it in against buying a TDV8 RR you must be nuts!

I did say "intellectual excercise" at the start of the thread, but yes it is a fair assessment that I'm nuts.

18mpg is good for a RR. It would still be 18 with LPG, but the fuel is half the cost, so it would be the equivilent of 36mpg. (But even 10 extra mpg is good when you start with a low number if it doesn't cost too much to do over the expected lifetime - petrol is not going to get any cheaper is it?) The LSx would have been more for fun than economy.

The TDV8 is a long term idea. I'd wait for them to depreicate first

Eliot - your MPG seems a little low compared to mine. 20+ is normal from mine for a long run at around 70mph.

Pete - I see a Top Gear style challenge there