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IS250 V6 - Any one LPG theirs?


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Hi all,

 

I have decided I will keep this IS 260 for the next 6 years or so.

Being the V6,  would it be cost effective for me to have an LPG installation?

I guess my annual miles to be around 11,000

What size tanks would fit in the boot spare wheel well?

Thanks all

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Direct injection and LPG.. You would need to bypass entire fuel delivery system, whats more you would need kill engine "Smart" ECU as well. I believe is either not technically feasible and maybe even impossible.

For me whole idea sounds fishy... buying premium car and trying to save on petrol .. nahhhh 

Maybe that is only my opinion, but it is like buying premium breed animal for breeding and then castrating it. In my country such crime was very popular ( I have seen friend father getting LPG into his MB CL65AMG and ML320 ... what a joke!). I guess Audi A6 2.0tdi is better option then...

As well on such low miles even cheap "cowboy" LPG system would't pay off.. 

Simple math - LPG - 1l ~0.65/Petrol - 1l ~1.10. Car will used 20% more LPG, hence that weighted prices would be respectively: 0.78/110

Average MPG on Lexus IS250.. lets say ~26.5 = 11000 / 26.5 x 6 = 2490 gallons (~8.9l/100km x 17700 x 6 = 9450l ). Based on this simple calculation at best you would be able to save ~£2600 at best. This is only if engine not going to break (which it will in certain extent).

So now if you take the price of decent LPG system off the £2600 and as well add the price of engine rebuilt in your risk list... you not going to save much but will risk to loose quite a lot (and all that is the least - not technically feasible due to advanced ECU system and other linked electronics).

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Confirming previous replies - you almost certainly can't do it, because of the direct injection. The injector tips would melt - they are normally cooled by the petrol passing through them. You lose that with LPG direct injection. It is technically possible to arrange for petrol to be injected some of the time to keep the injectors cool, but the system has to be designed specifically for each model of car and it is very expensive. I think it very unlikely that a kit has been designed for IS250s - there just aren't enough of them to make development worthwhile.

I could be wrong - check with a few LPG conversion specialists to see if it can be done. Only a very few DI cars can be converted.

And I rather agree with Linas!

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21 hours ago, Linas.P said:

Direct injection and LPG.. You would need to bypass entire fuel delivery system, whats more you would need kill engine "Smart" ECU as well. I believe is either not technically feasible and maybe even impossible.

For me whole idea sounds fishy... buying premium car and trying to save on petrol .. nahhhh 

Maybe that is only my opinion, but it is like buying premium breed animal for breeding and then castrating it. In my country such crime was very popular ( I have seen friend father getting LPG into his MB CL65AMG and ML320 ... what a joke!). I guess Audi A6 2.0tdi is better option then...

As well on such low miles even cheap "cowboy" LPG system would't pay off.. 

Simple math - LPG - 1l ~0.65/Petrol - 1l ~1.10. Car will used 20% more LPG, hence that weighted prices would be respectively: 0.78/110

Average MPG on Lexus IS250.. lets say ~26.5 = 11000 / 26.5 x 6 = 2490 gallons (~8.9l/100km x 17700 x 6 = 9450l ). Based on this simple calculation at best you would be able to save ~£2600 at best. This is only if engine not going to break (which it will in certain extent).

So now if you take the price of decent LPG system off the £2600 and as well add the price of engine rebuilt in your risk list... you not going to save much but will risk to loose quite a lot (and all that is the least - not technically feasible due to advanced ECU system and other linked electronics).

Simple math - LPG - 1l ~0.65/Petrol - 1l ~1.10. Car will used 20% more LPG, hence that weighted prices would be respectively: 0.78/110

I only pay 48p per litre and I get 30MPG

For me whole idea sounds fishy... buying premium car and trying to save on petrol .. nahhhh 

There are many reason why people chose to run their cars on LPG 1. Its far kinder on the environment we live in. 2. Its also alot kinder on your engines as there are not the pollutants in LPG that are in petrol and shorten the life of your engines and its component parts. 3. No millionaire became a millionaire by throwing money away when there are cheaper alternatives. 

Cheap LPG cowboy systems never pay off in any instance.   If its a cowboy system just chuck the money straight down a drain it will save you alot of time and worry.

If you do your sums again with a more realistic price for LPG you might see a different picture. Mike.

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5 hours ago, vette said:

Hi all,

 

I have decided I will keep this IS 260 for the next 6 years or so.

Being the V6,  would it be cost effective for me to have an LPG installation?

I guess my annual miles to be around 11,000

What size tanks would fit in the boot spare wheel well?

Thanks all

If you go onto Profess in South Wales website, insert all your details and they will tell if it cam be done or not, you can believe what they tell you. Mike.

http://www.professautogas.co.uk/index.php/about-us/quick-quote

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Below is a comprehensive answer posted in Jan 2015 by LOC member ChumpusRex

It is because of the fuel injection and ECU setup, and the IS being a rare car, that no one has bothered making a kit for it. There are plenty of DI cars out there which have LPG conversion kits available.

Direct injected conversions are mechanically easier than normal conversions, because you don't need any mechanical engine mods - like gas injectors, vaporisers, etc. Direct injection systems work at super high pressure normally, and at these pressures, the LPG will be a liquid, so flow, pump and inject just like petrol. You just connect the LPG pipe to the engine's fuel pump via a selector valve (for petrol or LPG) and the LPG goes through the normal pump and injectors.

However, like all fuel injected LPG conversions, you need an ECU remap because of differences in combustion between LPG and petrol. The difference with DI, is that the ECU has a lot more control, and therefore you need a much more complicated remap. Designing an ECU map is a ton of skilled work, especially on modern DI ECUs which can have up to 250,000 different individual parameters to tweak.

I'm guessing that there has been no demand for the tuning companies to develop an LPG map for the IS250. In fact, I've not seen anyone offer a remap for the IS250 for anything - probably because of the complexity of the system, and the fact that Lexus have strong security systems on their ECUs to prevent unauthorised re-mapping.

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13 hours ago, piasek said:

I have to disagree with Linas. LPG in premium cars it's not a crime. I rather save on fuel if it's possible and use money I save to go on holiday with my family.

I believe it is little bit off-topic as IS250 cannot be fitted with LPG... so we rather discussing about LPG in general..

I do agree... If something comes with LPG from factory, designed for such purpose... I would definitely agree - LPG is greener, better RON (maybe stinks a little bit more than petrol)... Anyways - IS250 doesn't come with LPG from factory (nor does CL65AMG or ML320) - that alone means these car are NOT OK to be run on LPG. Any manufacturer runs millions (literally) of miles to test the engines and sets them up to be used with certain fuel... there is no way some cowboys can have budget or time to re-run all factory tests and to install LPG system without harming engine performance and reliability. LPG tank is by any means fire hazard in the boot... no matter what you say it is nowhere near as safe as factory fitter petrol tank (unless again factory fitted LPG).

To summarise - theoretically LPG is better than Petrol, greener, better to the engine and more efficient. Practically, except of very few cars e.g. WV Caddy such setup will always be less efficient (Less MPG on LPG), will hurt engine, will be inconvenient and possibly dangerous. 

I strongly believe that such DIY should be banned as unsafe... except few specific car models where it is financially feasible to conduct sufficient research and testing and where LPG system completely replaces Petrol (and is fitted instead of Petrol system components).

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My main answer was - it cannot be fitted to IS250. That is true.

Whenever LPG is good for car or not is off-topic. Whats more, it is really just individual opinion and experience rather than hard facts. The fact is that LPG theoretically is better than petrol, but at the same time experience shows that it is not, engines are getting damaged and shows excessive wear, that real life MPG is worse than theoretical.

Garages are certified to fit the LPG, which means it won't leak or explode with the turn of the key. Certified doesn't mean they did (or even capable of doing) complete impact analysis to performance and longevity, or have carried out any tests. Even if they did.. that without doubt will be based on few certain engines types which are popular. Based on that it is unfair to assume that  - if LPG was excessively tested and works very well on 2l VW engine it will work equally well on 2.2l VW engine, even less likely on 2.5l V6 Toyota DI engine with "Smart" ECU.

To conclude - everything is possible, but when it comes to LPG.. making it right would be just to complex and expensive, therefore I assume all aftermarket LPG systems are not performing anywhere near their theoretical limit, nor gives theoretical advantage. 

The limited advantage is evident on large and hungry cars with high annual mileage. On relatively small and efficient IS250 it would never pay-off. Saying that 6th Gen LPG improves performance and MPG you should not forget to mention - when it is done on non-DI engine, without fuel management system. Obviously, adding DI LPG with custom mapped ECU gives advantage. But that is not because of LPG, but because standard injection was replaced with DI and engine additionally optimised with custom ignition/injection timing. 

Take for example difference between similar Toyota DI and non DI engines e.g. 2VZ-FE was predecessor for 4GR-FSE (IS250) similar V6 2.5l engine, but DOHC instead of D-VVTi with D4-DI.. there are other differences in design, but generally majority of power gain and efficiency are due to "D-VVTi / D4-DI". That said if you put advanced LPG to 2VZ-FE, it would be effectively upgrade to the engines technology and would give you noticeable gains (similar to those of D-VVTi / D4-DI), however if you do it for 4GR-FSE the gains will anywhere from minimal to negative, that is because the technology behind 4GR-FSE is either equal or even superior than latest LPG generation. 

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3 hours ago, Linas.P said:

I believe it is little bit off-topic as IS250 cannot be fitted with LPG... so we rather discussing about LPG in general..

I do agree... If something comes with LPG from factory, designed for such purpose... I would definitely agree - LPG is greener, better RON (maybe stinks a little bit more than petrol)... Anyways - IS250 doesn't come with LPG from factory (nor does CL65AMG or ML320) - that alone means these car are NOT OK to be run on LPG. Any manufacturer runs millions (literally) of miles to test the engines and sets them up to be used with certain fuel... there is no way some cowboys can have budget or time to re-run all factory tests and to install LPG system without harming engine performance and reliability. LPG tank is by any means fire hazard in the boot... no matter what you say it is nowhere near as safe as factory fitter petrol tank (unless again factory fitted LPG).

To summarise - theoretically LPG is better than Petrol, greener, better to the engine and more efficient. Practically, except of very few cars e.g. WV Caddy such setup will always be less efficient (Less MPG on LPG), will hurt engine, will be inconvenient and possibly dangerous. 

I strongly believe that such DIY should be banned as unsafe... except few specific car models where it is financially feasible to conduct sufficient research and testing and where LPG system completely replaces Petrol (and is fitted instead of Petrol system components).

"I do agree... If something comes with LPG from factory, designed for such purpose... I would definitely agree - LPG is greener, better RON (maybe stinks a little bit more than petrol)... Anyways - IS250 doesn't come with LPG from factory (nor does CL65AMG or ML320) - that alone means these car are NOT OK to be run on LPG. Any manufacturer runs millions (literally) of miles to test the engines and sets them up to be used with certain fuel... there is no way some cowboys can have budget or time to re-run all factory tests and to install LPG system without harming engine performance and reliability. LPG tank is by any means fire hazard in the boot... no matter what you say it is nowhere near as safe as factory fitter petrol tank (unless again factory fitted LPG)."

The above is complete and utter rubbish, you dont know what you are talking about. Just on tanks along if you were to hit a normal petrol tank with an hammer you will put a dent in it try the same thing on an LPG tank you will break the hammer and your wrist as well. LPG does not hurt engines run a petrol engine next to an LPG engine and the petrol one will fall to bits first. The only thing I agree with you is that DIY installs should be banned. Engineers should be properly trained and have the same system in place which governs the industry for domestic gas as for the rest of it I think you have been listening to the experts down the pub too much. Mike.

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48 minutes ago, piasek said:

Just to correct you Linas. Once again, new generation of LPG actually increase performance.

LPG tanks are much safer than petrol/diesel tank. Both in normal use and in case of accident.

I don't know why you keep repeating "unless factory fitted" as components that are used will be exactly the same. There is a lot of manufacturers abroad that offer LPG when you buying new car and they are fitted after the car leaves factory.

Garages that are converting cars to run on LPG are fully certified so I don't know what is your point about DIY. For your information it means Do It Yourself.

Please don't give us any more false information about LPG.

Garages that install LPG aren't sadly certified by anyone you can set up today and start installing straight away. Do not take any notice of UKLPG they are just a self appointed governing body which they would like you to think they are backed by the government but they are not. They are just a private co that cons people into thinking they are. 

I agree with you on the rest of Linas rubbish. Mike.

 

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4 minutes ago, Bluesman said:

Garages that install LPG aren't sadly certified by anyone you can set up today and start installing straight away. Do not take any notice of UKLPG they are just a self appointed governing body which they would like you to think they are backed by the government but they are not. They are just a private co that cons people into thinking they are. 

I agree with you on the rest of Linas rubbish. Mike.

I don't think were at the same page Mike... you are talking about what it could or should be, I am talking about what it is.

You agree, there is in fact no governance or industry standard - yet you claim installations are fine and only gives positive results... To say the least  - it don't make sense (not going as far as call that rubbish)... 

As well don't forget we are talking here about "state of art" 4GR-FSE getting castrated and not about "last century" 1UZ-FE getting some nuts..

 

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On 13/05/2016 at 3:00 PM, Linas.P said:

I don't think were at the same page Mike... you are talking about what it could or should be, I am talking about what it is.

You agree, there is in fact no governance or industry standard - yet you claim installations are fine and only gives positive results... To say the least  - it don't make sense (not going as far as call that rubbish)... 

As well don't forget we are talking here about "state of art" 4GR-FSE getting castrated and not about "last century" 1UZ-FE getting some nuts..

 

You are correct in thinking that you and I are not on the same page. All of what you have put about the effects of LPG vs Petrol is rubbish.

The industry is not governed by any government body.

I have had installed LPG on various cars and run on LPG for around 17 years now. I have never had a cowboy system fitted and yes I do say all the cars I owned or have owned are safe.

At no time have any of the cars I have or had ever had engine wear problems because of running them on LPG. One of my ex cars now approaching 300,000 miles is still going strong. If cars do suffer engine problems then they were there before the LPG was installed.

"state of art" 4GR-FSE I dont have a clue what this is meant to mean.

How many cars have you had running on LPG?

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5 minutes ago, Bluesman said:

How many cars have you had running on LPG?

Never felt so low to own LPG car...

Lets say... I am enjoying the moments when I fill my tank with petrol and is part of ownership experience.. Sniffing LPG and fiddling with refill valves + caring tank with explosives instead of spare tire would ruin it..

Would even take IS220d (I know!) any day over IS250 LPG.. thanks God it is not possible...

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Well if anyone wants to save money don't buy v6, go for prius,ct200h,is300h  which is already factory fitted with hybrid system.most cars I seen  fitted with lpg are mainly from abroad.there is a place in barking they eastern European who fit lpg. There r London taxi fitted with lpg which r approved by tfl.also u can put lpg on London tx1,tx2 approved by tfl at cost of £8000.

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14 minutes ago, Linas.P said:

Never felt so low to own LPG car...

Lets say... I am enjoying the moments when I fill my tank with petrol and is part of ownership experience.. Sniffing LPG and fiddling with refill valves + caring tank with explosives instead of spare tire would ruin it..

Would even take IS220d (I know!) any day over IS250 LPG.. thanks God it is not possible...

As I thought you dont have a clue. I do not sniff LPG and I do not have to fiddle around to connect the pump hose and believe you me if a tank of petrol was to explode on you you wouldn't be posting on any forum anywhere after that.  The fumes alone from petrol should they ignite would give you a good idea of what it would be like to be caught with a flame thrower. As there are no fumes escaping when an LPG tank is being filled you never have to worry about being an extra in Apocalypse Now.

 

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I believe one does not need to set himself on fire to "have a clue" how it feels. Same with LPG... why do I need to try something which I know is wrong.

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Just now, Linas.P said:

I believe one does not need to set himself on fire to "have a clue" how it feels. Same with LPG... why do I need to try something which I know is wrong.

I think we will leave it there. Mike.

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1 minute ago, Bluesman said:

I think we will leave it there. Mike.

Exactly.. and thanks for ahmedali44 for summarysing it for us:

11 minutes ago, ahmedali44 said:

Well if anyone wants to save money don't buy v6, go for prius,ct200h,is300h  which is already factory fitted with hybrid system.most cars I seen  fitted with lpg are mainly from abroad.there is a place in barking they eastern European who fit lpg. There r London taxi fitted with lpg which r approved by tfl.also u can put lpg on London tx1,tx2 approved by tfl at cost of £8000.

This sounds about right - I would trust system for £8k... but that is more than reasonable IS250... so not exactly "saving".. certainly not on 66k miles

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Only cars I knew were converted to lpg were ls400 who used it for chauffeuring back in days, no problems,any1 remember vauxhall omega think it was 2litre knew someone had that converted lpg,had nothing but aggro but was used for chauffeuring so was saving money as done 30-40k per yr but normal person who drive 4-5k a yr worth spending approx £2500 for having system installed, it's not gonna pay for it self in long run.

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I have always admitted there are far too many cowboy outfits out there that let the industry down but in this country its the same in any trade or industry although we think we are regulated up to the hilt as often or not the rules are easy to get round, no rules there in the first place or just ignore them as well as that there is never anyone around that can enforce the rules/laws or cant be bothered to enforce the rules/laws and so it goes on.

I have seen and smelt some terrible LPG installs which are basically mobile bombs but having said that have you ever heard of one going bang (mates down the pub dont count) Mike.

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4 hours ago, Linas.P said:

Never felt so low to own LPG car...

Lets say... I am enjoying the moments when I fill my tank with petrol and is part of ownership experience.. Sniffing LPG and fiddling with refill valves + caring tank with explosives instead of spare tire would ruin it..

Would even take IS220d (I know!) any day over IS250 LPG.. thanks God it is not possible...

Excuse me Linas, but you enjoy filling your car with petrol and consider it part of the ownership experience?  Really?  You must lead a really boring life :tongue::smile:

As far as the rest goes, my understanding is that there is nothing wrong with LPG and if I did enough miles I would probably convert my car.

Also, your assumption that manufacturers put millions of miles on their engine to tune them to specific fuels isn't exactly accurate since we know that they set the cars up to use the worst fuels to protect their engines.  That is where the gains from chip tuning come in.  So there is nothing to say that cars wouldn't run the same - or better even - on LPG as opposed to petrol.

I am curious about this direct injection making it impossible or not question.  I know Bluesman quoted ChumpusRex, but do we have a definitive answer on this?

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Maybe lets stop pretending someone here are converting to LPG to improve performance or save environment - the goal is quite clear - SAVE MONEY... 

It is self-defeating to discuss this on Lexus forum, because the brand itself was not set-up for saving money... So wise advice would be - if you want to save money don't buy Lexus (or Jaguar, or Lamborgini).. Fitting LPG in Lexus sounds extremely pointless. 

http://www.prinsautogas.com/en/products/directliquimax_system/directliquimax_system.html

At the bottom of this page there is a link to list of vehicles with DI that can be converted.

 
 
 

As I have explained previously, DI is not the only problem... More problematic is ECU which controls both injection and valve timing. If you add LPG the system would go completely bonkers... Lexus IS250 is not on the list for good reason. And anyways it is not like fuel hungry, or would benefit significantly from LPG... that's not LS400 with engine from 1988 (Mike)

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