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RRUK
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Member Since: 08 Jun 2007
Location: UK
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United Kingdom 2019 Range Rover Vogue SE SDV8 Santorini Black
The FACTS about LPG conversions

There is another thread here about LPG but not much detail. I looked into this myself recently, I thought that maybe getting rid of the TD6 and it's 104 litre diesel fill ups at the extortionate rates could be lessened. I had a real whizzy idea of getting a 2nd hand Supercharged Range Rover with one year's warranty, low miles for about £30k, then spending the money on an LPG conversion and having the best car ever for little fuel expense.

I did lots of research and here are the facts before you jump into it. These are Base 101 and onwards...

    LPG conversions can only be done on petrol engine cars (of course!)
    Conversions costs vary from about £1700 for a small family car upwards
    JE Engineering will do it for £3K for a normal 4.4 petrol, or £3500 + VAT for a Supercharged FFRR, RRS SC or D3.
    The Supercharged engine, the Sport and the Disco conversions have been problematic and have engine fault light issues - JE are suspending conversions until this is fixed
    You'd need to spend a large amount on Petrol or diesel to recoup the costs ( I do a minimum of 20K a year and would still need to achieve 16 mpg from a FFRRSC to pay it back within 2 years!)
    Doing 20,000 miles a year yould save £1600 on fuel as compared to diesel if you manage 16mpg.
    There is a minor reduction in your Tax disc for getting it done (£10-20!)
    Your insurance WILL increase marginally
    You CANNOT take your converted car on the Eurotunnel
    Any Land Rover warranty on the car is completely and TOTALLY voided. Even if the stereo breaks, you cannot claim on warranty, they will not touch your car.
    You will also have to take your car elsewhere for servicing for the same reason
    Your MPG will decrease on LPG by about 2-3 miles and the performace is marginally affected also
    The LPG tanks although stated as 95 litres can actually only get about 85-88 litres filled and sit in the spare wheel well
    You keep the standard fuel tank so you effectively have nearly 200 litres of fuel on board
    The engine always starts on petrol then switches to LPG automatically
    A small interior switch tells you the amount of LPG left
    The conversion takes about 5 days and typically comes with a 2 year warranty


For these reasons and more I decided to not go ahead with a conversion, having a Range Rover out of warranty is not what I am personally looking for but for some doesn't matter.

It is said that it's only worthwhile doing a conversion if you do high miles but as I found, even for 20K/year, the return on investment is still 2 years, and that's if you can achieve 16mpg from the FFRRSC engine, which I think is not possible when you take into account the MPG drops by 2-3 when running on LPG.

I did a huge spreadsheet charting different mileage and MPG figures againt the price of LPG and Diesel and in the end, you'd need to be doing about 30,000 miles to get a quick enough return.

I hope some of this has been useful to you.

Adam Discovery 4 HSE
1998 110 TUM HS FFR Hard Top XD WOLF
1982 Series 3 Hard Top

*Gone:L462 D5 HSE LUX, L663 Defender 110 HSE, Discovery 3 HSE, 2014MY Range Rover Sport 5.0 Supercharged AB Dynamic; L405 Exec Vogue SE 4.4, 5.0 Supercharged Autobiography, Defender TDCi XS CSW, Defender TD5 HT, Vogue SE TDV8, Vogue TD6, RRSport SC 4.2V8, Classic 3.9 Vogue Auto, Land Rover Series 3 SWB

Last edited by RRUK on 24th Feb 2009 3:13pm. Edited 2 times in total

Post #630 23rd Jun 2008 10:35am
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ammars27



Member Since: 22 Jul 2008
Location: Essex
Posts: 9

2003 Range Rover Vogue 4.4 V8 Buckingham Blue

You can get 4.4 petrol lpg converstion done by alternative fuel in barking essex with 5 year, 60,000 miles warrenty ,best prinz system installed for only 1850 pounds, had it fitted last week and works like dream!

Post #694 22nd Jul 2008 11:43pm
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shmoogle



Member Since: 26 Mar 2007
Location: Mongolia (where the Mongs come from)
Posts: 108

United Kingdom 2008 Range Rover Autobiography Supercharged Chawton White

Do they warranty the whole car, replacing the lost LR warranty? If not, then the above still applies Very Happy Halfway Down The Stairs,
Is the Stair Where I Sit.

Post #698 23rd Jul 2008 1:12pm
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ammars27



Member Since: 22 Jul 2008
Location: Essex
Posts: 9

2003 Range Rover Vogue 4.4 V8 Buckingham Blue

shmoogle wrote:
Do they warranty the whole car, replacing the lost LR warranty? If not, then the above still applies Very Happy


Well if you have a car thats out of warrenty, then its the best option, i dont know many people buying a £70,000 car and then worry about fuel bills! it the used car market user that will most likly get it converted to lpg, I still have not heard of anyone offering a 5 year warrenty though!

Post #701 23rd Jul 2008 1:23pm
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StevieH



Member Since: 05 Feb 2009
Location: Cumbernauld, Lanarkshire
Posts: 117

United Kingdom 2004 Range Rover Vogue 4.4 V8 Java Black

My 4.4 is booked in for conversion next week. there is a caution on all 4.2 S/C conversions. Apparently valve seal problem reported so most reputable garages will insist on installing a flash lube system which will add about £175 or so on to price of standard conversion. Also on our cars they need to relocate the air compresssor and never get the seal as good as factory standard ...as a result compressor is slightly noisier afterwards.

Post #2878 9th Feb 2009 11:09am
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RRUK
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United Kingdom 2019 Range Rover Vogue SE SDV8 Santorini Black

Thanks for the update on that one. Discovery 4 HSE
1998 110 TUM HS FFR Hard Top XD WOLF
1982 Series 3 Hard Top

*Gone:L462 D5 HSE LUX, L663 Defender 110 HSE, Discovery 3 HSE, 2014MY Range Rover Sport 5.0 Supercharged AB Dynamic; L405 Exec Vogue SE 4.4, 5.0 Supercharged Autobiography, Defender TDCi XS CSW, Defender TD5 HT, Vogue SE TDV8, Vogue TD6, RRSport SC 4.2V8, Classic 3.9 Vogue Auto, Land Rover Series 3 SWB

Post #2886 9th Feb 2009 5:17pm
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IKke



Member Since: 16 Aug 2008
Location: Brabant
Posts: 7

Netherlands 

RRUK. In your first post, were you talking about a G2 system or a G3 system?.

Post #6367 7th Jul 2009 4:07pm
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RRUK
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Member Since: 08 Jun 2007
Location: UK
Posts: 6349

United Kingdom 2019 Range Rover Vogue SE SDV8 Santorini Black

I'm not certain, we'd have to call JE Engineering to ask what theirs is Discovery 4 HSE
1998 110 TUM HS FFR Hard Top XD WOLF
1982 Series 3 Hard Top

*Gone:L462 D5 HSE LUX, L663 Defender 110 HSE, Discovery 3 HSE, 2014MY Range Rover Sport 5.0 Supercharged AB Dynamic; L405 Exec Vogue SE 4.4, 5.0 Supercharged Autobiography, Defender TDCi XS CSW, Defender TD5 HT, Vogue SE TDV8, Vogue TD6, RRSport SC 4.2V8, Classic 3.9 Vogue Auto, Land Rover Series 3 SWB

Post #6368 7th Jul 2009 4:40pm
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IKke



Member Since: 16 Aug 2008
Location: Brabant
Posts: 7

Netherlands 

Quote:
JE use OMVL, Tartarini or Prins sequential injection systems where LPG is introduced through one injector per cylinder. There is therefore no additional restriction in the engine inlet airflow & no reduction in power.

G3 system.
But I do miss something. The combustion temperature of LPG is higher than petrol. And this causes the valves to burn away slightly. So for an ideal conversion you also need hardened valves, or somthing that can handle the higher temperatures. Althought modern cars might be affected less than older cars, but that is just an idea and not based on anything I know. But with the newer liquid lpg injection systems this might be solved because it cools the air by expanding, but this is also a guess. Although there are a few car brands that support LPG use and also some brands that supply pre fitted systems.

Post #6383 8th Jul 2009 3:28pm
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delsilencio



Member Since: 08 Apr 2009
Location: toulouse
Posts: 116

France 2004 Range Rover Vogue 4.4 V8 Adriatic Blue

No problems with the BMW 4.4 engine(with or without flash lube) because it has hardened valve seats.
Later Jag engine hasn“t and so the valves will engrave the seats and that will force trouble (even with or without flash lube). XJC, RRV8, Series1 86 and 107% of real pleasure

Post #12994 11th Feb 2010 4:49pm
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Rob750



Member Since: 10 Oct 2010
Location: Epping
Posts: 18

2002 Range Rover Vogue 4.4 V8 Java Black

Interesting post, after about 2 yrs running on a BRC system I agree about a slight mpg degradation but it runs a fraction cooler on LPG , the low down and mid range performance is more lively and the engine is quieter . The loss of about 1-1.25 mpg is what I have experienced Regards

Rob

Post #37325 20th Nov 2010 11:13pm
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jime



Member Since: 04 Jan 2011
Location: Bristol
Posts: 5

2011 Range Rover Vogue SE 4.4 V8 Epsom Green

Have to say this seems to be a mixture of fact and "local dealers interpretation of warranty rules".
1. You can fit LPG to a diesel, however this system effectively replaces 10-20% of the diesel so is never going to be cost effective.
2. My admittedly last of the P38 v8 4.o was converted to the STAG system lpg for some £1400. some 8 months ago. Because Stag use all the original engine sensors etc. no probs at all.
Proffautogas of S wales do a "same day service" admitedly you have to arrive at 0700 and car is not ready until 1900 hrs - but they give you a loan car.
3. think maths may be wrong (admittedly using my average MPG around town)
20000 divided by 12 (mpg) = 1666
1666 x 4.5 = 7580 (litres)
7580 x £1.25 (unleaded) = £9475 cost of petrol
7580 x £0.71 (dearest lpg) £5381 cost of lpg
Savings = £4094 per annum.
Even using 17mpg as a base figure (my "on a run" mpg) the saving per annum is still £2858.
4. My vehicle is still under LR extended warrant (less than 100,000) no probs with servicing (but they do insist I lock car to petrol) only service petrol side and will only honour warranty claims that are reproducible on petrol and exclude cylinder head.

Post #44544 4th Jan 2011 7:43pm
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T24RES



Member Since: 22 Nov 2010
Location: Henley-on-Thames
Posts: 936

United Kingdom 

jime wrote:
Have to say this seems to be a mixture of fact and "local dealers interpretation of warranty rules".
1. You can fit LPG to a diesel, however this system effectively replaces 10-20% of the diesel so is never going to be cost effective.
2. My admittedly last of the P38 v8 4.o was converted to the STAG system lpg for some £1400. some 8 months ago. Because Stag use all the original engine sensors etc. no probs at all.
Proffautogas of S wales do a "same day service" admitedly you have to arrive at 0700 and car is not ready until 1900 hrs - but they give you a loan car.
3. think maths may be wrong (admittedly using my average MPG around town)
20000 divided by 12 (mpg) = 1666
1666 x 4.5 = 7580 (litres)
7580 x £1.25 (unleaded) = £9475 cost of petrol
7580 x £0.71 (dearest lpg) £5381 cost of lpg
Savings = £4094 per annum.
Even using 17mpg as a base figure (my "on a run" mpg) the saving per annum is still £2858.
4. My vehicle is still under LR extended warrant (less than 100,000) no probs with servicing (but they do insist I lock car to petrol) only service petrol side and will only honour warranty claims that are reproducible on petrol and exclude cylinder head.

71p we should be so lucky. 81p at my local shell garage Big Cry Ian

Post #44546 4th Jan 2011 7:47pm
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dan_uk_1984



Member Since: 12 Nov 2008
Location: Bude, Cornwall
Posts: 4014

United Kingdom 2006 Range Rover Supercharged 4.2 SC V8 Tonga Green

jime wrote:
Have to say this seems to be a mixture of fact and "local dealers interpretation of warranty rules".
1. You can fit LPG to a diesel, however this system effectively replaces 10-20% of the diesel so is never going to be cost effective.
2. My admittedly last of the P38 v8 4.o was converted to the STAG system lpg for some £1400. some 8 months ago. Because Stag use all the original engine sensors etc. no probs at all.
Proffautogas of S wales do a "same day service" admitedly you have to arrive at 0700 and car is not ready until 1900 hrs - but they give you a loan car.
3. think maths may be wrong (admittedly using my average MPG around town)
20000 divided by 12 (mpg) = 1666
1666 x 4.5 = 7580 (litres)
7580 x £1.25 (unleaded) = £9475 cost of petrol
7580 x £0.71 (dearest lpg) £5381 cost of lpg
Savings = £4094 per annum.
Even using 17mpg as a base figure (my "on a run" mpg) the saving per annum is still £2858.
4. My vehicle is still under LR extended warrant (less than 100,000) no probs with servicing (but they do insist I lock car to petrol) only service petrol side and will only honour warranty claims that are reproducible on petrol and exclude cylinder head.


Agree with the above - Proffess Autogas are good guys and the saving is a no brainer! 

Post #44547 4th Jan 2011 7:48pm
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A1GSS



Member Since: 24 Dec 2010
Location: Saffron Walden, Essex
Posts: 1973

England 

delsilencio wrote:
No problems with the BMW 4.4 engine(with or without flash lube) because it has hardened valve seats. Later Jag engine hasn't and so the valves will engrave the seats and that will force trouble (even with or without flash lube).


So, does this suggest that an unmolested BMW-engined FFRR will make a great candidate for a new LPG conversion?

I'm looking at LPG as my only affordable route into FFRR ownership ...

Thanks for any advice. Graham

____
Gone: 10MY L320 RR Sport HSE, Ipanema Sand
Gone: 20MY Jaguar iPace HSE, Silicon Silver
Gone: 17MY RR Evoque SE Tech, Loire Blue
Gone: 08MY Discovery 3 XS, Stornoway Grey
Gone: 07MY FFRR TDV8 Vogue, Stornoway Grey

Post #44801 6th Jan 2011 8:40am
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