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I am considering converting my 2004 LS430 to run on LPG - calculated a significant fuel saving were I to do this

I have done some homework myself (costs, tank location etc) but wanted to start asking other members for their experiences since I can believe I'm the only one considering it

It seems that the best tank to use is a toriodal tank replacing the spare wheel (it takes a whopping 95 L so should get about the same range as with the existing petrol tank. You need to carry a tyre foam inflator in case you get a puncture.

Also I am told that all jap engines require an auxilliary lubrication system to cope with LPG (which is much 'dryer' than petrol) and can cause valve seat wear otherwise. Apparently Jap engines do not use hardened vale seats (other manufacturers do, so this additional lube is not required).

Cost of a good quality install seems to be around £2k and takes a week (I've been advised to avoid those companies who say they can do it "in a day" - it's quite a big job).

Does anyone have other considerations to add to this.

What I really want to know is whether anyopne has done it and what teh real-life effects were

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I am considering converting my 2004 LS430 to run on LPG - calculated a significant fuel saving were I to do this

.....

What I really want to know is whether anyopne has done it and what teh real-life effects were

There have been numerous discussions about this, you can use the search option to find them. A few points, the tanks only fill to 80% capacity, its a safety feature. The mpg figures for lpg will be a little lower than with petrol . Stations selling lpg are not a numerous as petrol stations, and an lpg depot is rarer but worth finding for 5 p a litre cheaper price.

All of the above means, get a bigger tank than you think you need.

My 92 LS400 came with a single point system, and a cylinder tank in the boot. I fitted a toroidal tank in the spare wheel well - two tanks are perfectly simple to have, involving a T piece and a non-return T piece, but more hassle for the installers.

I don't think the lube system is neccesary

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I've run lpg cars for ten years and its brilliant. Engine runs hotter in the chamber but cooler overall. DO go for the 'flashlube' valve seat lubrication system and keep it topped up - I just bought an IS200 with a brilliant lpg system but the loon before me never topped up the lube system which has resulted in NO COMPRESSION on cyl one - i.e. BURNED VALVE SEATS. Flashlube is about £16 a litre, should last well over a year (it uses 1ml per litre of fuel). There are plenty of filling stations - download a free satnav plug-in or buy a map telling you where they are. Fuel at about 60-70p/litre just now (April 2010) and since it has a slightly lower energy-density than petrol you get a few less mpg. But since its already a vapour it burns better so mpg loss is not so bad. I reckon its 70% of the cost of pertol for the same MILES. Also its environmentally good: you know those flares on top of oil wells? Thats the gas being burned off. So why not burn that same gas in an engine, and run close to carbon neutral (yee yes, energy is used in compressing it to a liquid, carrying to the filling station and selling it to me).

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Hi I run a 98 vvti engine(same as yours) on lpg the ls 400s & 430s dont need flash lube as they dont suffer valve seat ressesion, the lexus 6 cylinder models do, I run a brc plug & drive system with a doughnut in the wheel well, I cary 2 large tubes of ride on sealent & a 12v compressor in case of a punture ( lots of new cars dont have a spare wheel now & have the same stuff). On a run at motorway speeds i do 250 to 275 miles to £30 worth of gas at 60p a litre, in heavy London suburb traffic I get 175 miles to £30.

My system cost £1750 fitted & has paid for its self in 18 months my mate has a 93 ls400 converted at 90k now has 215k on it no flash lube & runs perfect still, He has just bought a 430 & had this converted aswell no flash lube. Go for it you know it makes sense. ta Mark

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£1399 I can get you £50 off this conversion if you let me know your going for it

It is a a flashlubed multi-point system so it'll make sure your engine definetly won't get valve seat wear, i've been running my mk3 LS 400 on it for 6 months and 10,000 miles now no problems at all. Anymore questions let me knoe, it comes with 1 year warrenty on parts and 2 years on labour.

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£1399 I can get you £50 off this conversion if you let me know your going for it

It is a a flashlubed multi-point system so it'll make sure your engine definetly won't get valve seat wear, i've been running my mk3 LS 400 on it for 6 months and 10,000 miles now no problems at all. Anymore questions let me knoe, it comes with 1 year warrenty on parts and 2 years on labour.

Yep thats the same firm that converted my mates 430, just state you dont mind them taking a little longer to do a tidy job.

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I am considering converting my 2004 LS430 to run on LPG - calculated a significant fuel saving were I to do this

I have done some homework myself (costs, tank location etc) but wanted to start asking other members for their experiences since I can believe I'm the only one considering it

It seems that the best tank to use is a toriodal tank replacing the spare wheel (it takes a whopping 95 L so should get about the same range as with the existing petrol tank. You need to carry a tyre foam inflator in case you get a puncture.

Also I am told that all jap engines require an auxilliary lubrication system to cope with LPG (which is much 'dryer' than petrol) and can cause valve seat wear otherwise. Apparently Jap engines do not use hardened vale seats (other manufacturers do, so this additional lube is not required).

Cost of a good quality install seems to be around £2k and takes a week (I've been advised to avoid those companies who say they can do it "in a day" - it's quite a big job).

Does anyone have other considerations to add to this.

What I really want to know is whether anyopne has done it and what teh real-life effects were

hi. i am on my 3rd lpg car- the 2nd 430. i do 50k a year.get a professional job done,you will notice the difference in performance and economy.no difference on tickover on my car( 2004 ls 430). flash lube or prins valve care is a must!!!- your valve seats will go eventually!!(from experience.)
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I am considering converting my 2004 LS430 to run on LPG - calculated a significant fuel saving were I to do this

I have done some homework myself (costs, tank location etc) but wanted to start asking other members for their experiences since I can believe I'm the only one considering it

It seems that the best tank to use is a toriodal tank replacing the spare wheel (it takes a whopping 95 L so should get about the same range as with the existing petrol tank. You need to carry a tyre foam inflator in case you get a puncture.

Also I am told that all jap engines require an auxilliary lubrication system to cope with LPG (which is much 'dryer' than petrol) and can cause valve seat wear otherwise. Apparently Jap engines do not use hardened vale seats (other manufacturers do, so this additional lube is not required).

Cost of a good quality install seems to be around £2k and takes a week (I've been advised to avoid those companies who say they can do it "in a day" - it's quite a big job).

Does anyone have other considerations to add to this.

What I really want to know is whether anyopne has done it and what teh real-life effects were

hi. i am on my 3rd lpg car- the 2nd 430. i do 50k a year.get a professional job done,you will notice the difference in performance and economy.no difference on tickover on my car( 2004 ls 430). flash lube or prins valve care is a must!!!- your valve seats will go eventually!!(from experience.)

This is one reason why I didn't go for an LPG conversion in the end on mine. There was so much differing opinions in terms of weather Flashlube was needed or not on the 3UZ-FE engines that it made me wonder weather they knew what they were on about. All the so called experts out there were offering to much differing advice. In my opinion, stay well clear untill there is a standard, not just recomendations from different dealers.

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My wife's 1998 LS400 Mk4 has just been converted to a Prins VSI system by Dual Fuel systems in Woking - no lube recommended - the car does 15k a year.

I'm not overly concerned if the valve seats are affected after the 2 year warranty - obviously if they do burn out I'll have a bit of work to do.

The guys at Dual Fuel recon there will not be a problem - and they state that they have converted a number of LS's that cover far higher mileage than the wife's car with no problems.

It's early days for the economy side of things - but performance wise there is no difference - sport mode stays on and the idea of using cruise control to and from Caroline's office has been ditched.

Caroline has kept a note of every tank of fuel and mileage since she's owned the LS - which is only 16 months - but does show an average of about 22mpg on petrol most weeks - on weeks with longer journeys (>25 miles a journey) that improves to above 25mpg.

After a few months of lpg I'll post the results.

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My wife's 1998 LS400 Mk4 has just been converted to a Prins VSI system by Dual Fuel systems in Woking - no lube recommended - the car does 15k a year.

I'm not overly concerned if the valve seats are affected after the 2 year warranty - obviously if they do burn out I'll have a bit of work to do.

The guys at Dual Fuel recon there will not be a problem - and they state that they have converted a number of LS's that cover far higher mileage than the wife's car with no problems.

It's early days for the economy side of things - but performance wise there is no difference - sport mode stays on and the idea of using cruise control to and from Caroline's office has been ditched.

Caroline has kept a note of every tank of fuel and mileage since she's owned the LS - which is only 16 months - but does show an average of about 22mpg on petrol most weeks - on weeks with longer journeys (>25 miles a journey) that improves to above 25mpg.

After a few months of lpg I'll post the results.

i have had 3 cars done by dual mfuel.they arte very good.however they recommened i fit a prins flashlube to my latest car (2004 ls 430).i had valve problems(1 cylinder no compression) on my last one after 230k)

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Will the LS400 cruise control still work after an LPG conversion.

I have a 1995 Mk-3 car.

Hi yes it will, it doesnt do any harm to have a flash lube fitted, there is one on mine, I just dont use it

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There's an article in the current 'Practical Mechanics' about LPG. Might be worth looking at. My last two cars (BM's)both had LPG when I bought them and just loved the low running costs.Only one LS400 up here for sale with LPG, an 'M' reg for £2000. No thanks.

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