I ran an EVO 4 on LPG, there are some things you need to consider before fitting the LPG...

Firstly, LPG isn't great, your engine WILL wear quicker, it's a dry fuel so your engine and fuel system is getting no lubrication,
Resale value, recently we tried to part ex a family, professionally installed, 320 estate, for a New Toyota Aygo, the dealer offered us 50% LESS than market value, due to not being able to warranty LPG kit and resale value.
Thirdly, fuel, you will have both a smaller tank range on LPG AND it will go less distance, so eg. 50 litres of LPG will give you what 35 litres of petrol gives you in distance.
Fourthly, the system adds weight to the car, take up your spare wheel space or go as a separate tank in the boot.
IT WILL need declaring on your insurance, it will also put the cost up, depending on your company, but most do.
This was the biggy for me with the EVO... LPG kits are limited, they work very badly on turbo cars, however an LPG nozzle is pretty max'd out at around 200bhp on a 4 cylinder, they can get bigger injectors, bigger fuel systems, but the high end systems for a car running 250bhp+ (no idea what your 330 is running) cost around £2500 - £3000 plus... The good thing is, BMW's DO make excellent LPG cars, as they are six cylinders and not 4, you need smaller injectors than you would need on a 4 cylinder, however if you are running nearer the 300 mark, i would stay clear.
There is the issue of the filler going somewhere in the bodywork too.

Latly, LPG is good, it's better for the environment and currently has 0 tax on it, However this isn't going to last, there is only so long before the government start to tax it, anytime in the next few years, so yes, it will save you money, but in my opinion it isn't worth the space you will lose, extra weight and cost. However if you plan on keeping your car forever, it's worth it. My Grandfather in law has owned his for 10 years, the only issues needing done to the kit were a regulator (£50 fitted) and a new pipe under the car when a section hit a speed bump (£10 fitted) the car has no running issues and is fine 10 years later... However it is a 320 and the guy who fitted the kit said, don't get one on a performance motor.

PS. If you do get one, go for a PRINS kit, they are the Daddy of LPG, there are a LOT of cheaper alternatives, but the injectors are worth sod all, you need either Yellow or Brown injectors for your car to cope, otherwise, you'll starve the engine, hope this helps

 

I ran an EVO 4 on LPG, there are some things you need to consider before fitting the LPG...
Can you please explain, how the fuel lubricate the engine and what is the lubrication capability of petrol??? 🤔🤔🤔

Firstly, LPG isn't great, your engine WILL wear quicker, it's a dry fuel so your engine and fuel system is getting no lubrication,
Resale value, recently we tried to part ex a family, professionally installed, 320 estate, for a New Toyota Aygo, the dealer offered us 50% LESS than market value, due to not being able to warranty LPG kit and resale value.
Thirdly, fuel, you will have both a smaller tank range on LPG AND it will go less distance, so eg. 50 litres of LPG will give you what 35 litres of petrol gives you in distance.
Fourthly, the system adds weight to the car, take up your spare wheel space or go as a separate tank in the boot.
IT WILL need declaring on your insurance, it will also put the cost up, depending on your company, but most do.
This was the biggy for me with the EVO... LPG kits are limited, they work very badly on turbo cars, however an LPG nozzle is pretty max'd out at around 200bhp on a 4 cylinder, they can get bigger injectors, bigger fuel systems, but the high end systems for a car running 250bhp+ (no idea what your 330 is running) cost around £2500 - £3000 plus... The good thing is, BMW's DO make excellent LPG cars, as they are six cylinders and not 4, you need smaller injectors than you would need on a 4 cylinder, however if you are running nearer the 300 mark, i would stay clear.
There is the issue of the filler going somewhere in the bodywork too.

Latly, LPG is good, it's better for the environment and currently has 0 tax on it, However this isn't going to last, there is only so long before the government start to tax it, anytime in the next few years, so yes, it will save you money, but in my opinion it isn't worth the space you will lose, extra weight and cost. However if you plan on keeping your car forever, it's worth it. My Grandfather in law has owned his for 10 years, the only issues needing done to the kit were a regulator (£50 fitted) and a new pipe under the car when a section hit a speed bump (£10 fitted) the car has no running issues and is fine 10 years later... However it is a 320 and the guy who fitted the kit said, don't get one on a performance motor.

PS. If you do get one, go for a PRINS kit, they are the Daddy of LPG, there are a LOT of cheaper alternatives, but the injectors are worth sod all, you need either Yellow or Brown injectors for your car to cope, otherwise, you'll starve the engine, hope this helps

 

usefull info there,ive checked insurance quotes with and without a kit and theres not much in it, ive had a look at fitting it myself and looks fairly straight forward,ive fitted nitrous kits and engine conversions over the years but just need to make sure i get a good kit!
i beleieve most insurance companies want a certificate but read you can register them yourself as theres a lot of cars going about with kits before certificates where needed but i need to look into more info on that?
ive read that also about the tanks only taking 80% capacity and they do less mpg than petrol but surely it has to be better in the long run saving wise especially with the cost of fuel but then again this greedy goverment wont hold back if theres tax to be made!!
im quite concerned about the engine wear though ive not read anything on that yet but will do,powerwise the 330's are supposed to run 230 bhp and mines totally standard!

 

The kit on mine will go up to 350BHP and above that you add an extra outlet to the reducer to increase flow to solenoids.

Your tank does weigh but the gas inside it weights lighter then the petrol you aren't carrying so you don't do too badly on weight.

The tank weighs 20KG to 30KG empty at a guess.

Plus 40 Litres of LPG @ 0.54KG = 21.6KG
Minus 50 Litres of unleaded @ 0.74 = 37KG (Leaving about 2 or 3 gallons in the tank)

Adding that up it looks like I'm about 16KG heavier with a full tank of gas and a splash of petrol.

Anyway think of it as half the bag of cement people say to throw in your boot for winter traction lol.
I took out my full size spare and bought a 16" space saver off an auction site so I have lost a very small bit of boot space, or if like a lot of people you have no spare and a can you lose nothing space wise.



I think CBRbiker13 said it all when he said "it will save you money".

You need to work out how much it costs you to fit and how many miles you do so you can work out the payback period.

I get about 25mpg and can easily get more diving miss daisy style but at around £3.30 a gallon that's getting equivalent to late forties to fifty mpg at petrol prices.


Everyone swears by whatever kit they were sold by the people that tell them it is the best.

Thirdly, fuel, you will have both a smaller tank range on LPG AND it will go less distance, so eg. 50 litres of LPG will give you what 35 litres of petrol gives you in distance.

My tank fits completely in the spare wheel well. About 53 lites if I remember correctly but they only fill 80% so mine typically takes 34 to 38 litres.
Range wise I've tanked up and gone from Bolton to Wells below Bristol (nearly Bath in fact) - 200 miles and still had gas left. I get between 185 and 225 miles depending.
If I had gone for a tank about an inch and a half higher, pushing the boot carpet up, I would have nearly the same rang as my petrol tank.

No one that has driven my car can feel a power difference. However, if on the flat I engage cruise and the OBC is showing litres per 100KM and you flip to petrol consumption goes down slightly so the car does notice and adjust.

it's a dry fuel so your engine and fuel system is getting no lubrication

Oh and I wouldn't worry about it being a dry fuel. Since lead has been removed from fuel hardened valve seats and guides are the norm. Plus anyone that knows about over fuelling on petrol engines knows it doesn't lubricate, bore wash leads to excessive wear. However, you can get top end lubrication kits for LPG systems.

As for your fuel system getting no lubrication, that's wrong. my fuel system is still pumping petrol around, it just isn't openeing the injectors anymore when running on LPG

 

Don't forget it won't run on LPG straight from start either, it starts on petrol, then switches, longer in winter, quicker in summer

 

Very true, mine is set to switch to LPG early, so about a mile when it was minus 10, this weather about a quarter, mosthly within 5 mins, but if your 2 miles is straight off the drive and 2 miles with no delays or junctions and that is all you use it for payback could be a while.

 

My 330ci is conveterd to LPG, performance wise I don't notice alot of difference and the car runs just as good on LPG as petrol. My tank is in the spare wheel space also my LPG fill nozzle is hidden by the petrol cap and I just screw an attachment on to fill it up. You do get worst MPG on LPG but not by much and you have to bear in mind for the 2mile school run in the morning you will be running of petrol for the first couple of miles anyway as the car wont run on LPG cold.

 

couple of miles anyway as the car wont run on LPG cold.

Depending on how it's set up it really doesn't need to be that far

 

hi guys cheers for replys,ive been looking at a few kits and seen one a bmw with the filler next to the fuel cap so its hidden behind the flap,its not a big issue but would prefer the hidden look.
ive read a few sites saying the italian kits are good quality but alot are rebranded same stuff?
im definately going to do it and hopefully in next few weeks as i got a lot of trips planned with the wife and kids and we fancy driving to france then to spain in summer so it should earn for itself there,ive heard that frnace and other country's have different filling nozzles is this true and also you cant drive on eurotunnel with lpg cars as well?
any pics also would be great!

 

ps do you have to change spark plugs too?

 

I'm surprised no-one has asked how many miles the OP is doing.

Judging by the initial post I'm assuming not many... I don't think you can factor one off european road trips into a decision like this

So when you consider the huge outlay involved in doing an LPG conversion, how long is it going to take before you are actually saving money?

Personally I don't understand why anyone would even entertain the idea of an LPG conversion unless they were doing massive mileage and were keeping the car for long enough to see savings....

 

Agree with the above... I've looked into LPG quite a bit and after actually doing the sums I have found it would be cheaper to go back to a sludger.

The initial outlay only makes sense if you will be keeping the car for many years and doing big mileage. Also you will lose power, bear that in mind.

I wouldn't do it, it just isn't an elegant solution to the problem of MPG.

 

just sell yours and buy this one:lol
2005 BMW 320CI SPORT BLACK, lpg gas, lamborghini door, convertible | eBay

 

hi guys,your right there ive not stated exactly what sort of mileage we do,basically the wife does the school run as i said 2 miles each way every day but other the course of the week with other trips to the shops days out etc we tend to do about 120-150 miles a week and currently putting anything from £50-£80 a week in so i was hoping fitting an lpg kit would help lower this by quite a few quid?
i know i will lose a little power and mpg but ive driven range rovers running on the stuff and normal petrol and can say i didnt really notice that much power loss with it being a big engine anyway?
as regards keeping the car,weve just bought it and plan on keeping it for at least 4-5 years,we knew it would be slightly greedy being a 3 litre! but was looking at 330d sports and the figures i seen on the web for urban was only 25ishmpg so didnt think it was worth spending a bit more on a diesel plus ive never really enjoyed diesel cars as much as petrol and the 6 cylinder bmw is a sweet petrol motor that purrrs really nice and i noticed there seems to be a lot of stuff that go wrong on the diesels from swirl flaps to turbos on the 320d's then theres pumps and injectors that need coding if they go wrong and im not sure what the egrs are like on bmw diesels but when i used to work at a garage we always was replacing egrs too so just thought stick with the good old 6 cylinder!
the guys who have had lpg done can i ask what kits you have fitted?

 

I would say your mileage is very low 6,000/7,000 a year! You will probably not recoup the inital outlay in 4/5 years...
False economy imo.

There was a thread posted on here with tables comparing mpg from derv/petrol/lpg I can't find it if anyone could dig it up would be useful for the OP

 

hi mate that would be usefull if you could dig them figures be interested to see them,as regards fitting etc im gonna fit it myself and looking to spend around 4-500 on the kit,ive seen a few but taking my time to read up on them and see whats what!
i found a website where you put your yearly mileage and current mpg with cost of fuel and it came out with the system paying for itself in just under a year so i do think it would be worth it especially with fuel prices going up and up with no signs of coming down,saw diesel advertised near me today at 1.47 its getting overly silly now and the chancellor adding his 3p's worth will make it even more fun!
i believe that tax will go down a touch too if i reregister it as duel fuel lpg so every little helps!!

 

regards fitting etc im gonna fit it myself

So did I. The "how to" document is about 57 pages and about 90% complete

 

Personally I'd chop it in for a 330 diesel, bags more torque than the petrol, with a remap it will wipe the floor of a petrol 330.

Don't be so put off by all the hype around diesel unreliability, it's a much bigger problem with the 4-cylinder cars.

 

Personally I'd chop it in for a 330 diesel, bags more torque than the petrol, with a remap it will wipe the floor of a petrol 330.

I'd say this is a more sensible solution, re-sale value of the diesels are good aswell.

The thing baffling me here is this: "120-150 miles a week and currently putting anything from £50-£80 a week"

£80 is roughly 12.5 gallons of fuel.. If your only doing 150 miles on 12.5 gallons I work that out to be 12mpg.. I'd say you've either got a lead right foot or you've got a problem with your car!

Even if it's all short trips around town you should still be getting 20+mpg.....

 

I had an e39 535i which I purchased with the LPG already fitted. It does dry out the engine but there are a few things that would reduce the wear and tear.

1) Make sure you get the Prinns systemm (I think that is the correct spelling). It is the best system around and much less likely to ruin your engine
2) Always let the engine run on petrol at the beginning and end of a journey, as this will help to keep the engine hydrated.
3) Try not to use the LPG on short 5 minute journeys.

Hope this helps.

 

Always let the engine run on petrol at the beginning and end of a journey, as this will help to keep the engine hydrated.

I would love to see a detailed explanation of this, because to me it sounds like folk lore dating back to when there was lead in petrol required to lubricate valve stems and seats


Oh and I'll add that after a couple of oil changes your oil may be coming out nearly as clean as going in so think what that may do for your engine life.................

when you consider the huge outlay involved in doing an LPG conversion

£800 is huge?

Personally I'd chop it in for a 330 diesel, bags more torque than the petrol, with a remap it will wipe the floor of a petrol 330.

I'd say this is a more sensible solution, re-sale value of the diesels are good aswell.

Of course re-sale is higher, they cost more in the first place, so you have to lay out more money and probably lose as much on your trade in as opposed to market value to pay for the conversion.

Basically in the real world this may well have a longer payback than LPG conversion and you may not have the car you really wanted

 

LPG is a marmite thing, people who run it will swear it's amazing, but don't think your car will run the same as without it, it won't E36Coupe328 is bias, he runs his car on LPG, so champions it. All I am saying is go into it with your eyes wide open, yes it is cheaper to run, not it isn't the be all and end all and your car will not run the same on LPG as petrol, it just won't. Personally I would never own an LPG car ever again and I have driven several, from Prins kits, with high end jets running big power, to V8's running Zavoli kits that shouldn't be on the car and BRC kits that are well suited to a car, well installed running perfectly. But EVEN IF a car has the perfect kit, it will not run as nicely on LPG as it does on petrol, it just won't. There will also be a power difference.

All I am trying to do is give you a non bias view. If it's what you want, great, but drive one first.

 

but don't think your car will run the same as without it

As posted earlier, no one that has driven mine can tell.

E36Coupe328 is bias, he runs his car on LPG, so champions i

I've ran the same car without LPG for 16 months and the same car with for just under 12 months, that's a direct head to head comparison.

I think saying I am bias is just a way of trying to discount my answers without actually dealing with the points I make.

For example in my very first post on this thread I say..........

I think CBRbiker13 said it all when he said "it will save you money".

You need to work out how much it costs you to fit and how many miles you do so you can work out the payback period.

.........which makes me the first person to say do the maths before you choose if it is appropriate for you. A bias would be to suggest it was good for all regardless which I do not. It's a financial decision and has to pay it's way.

Personally I would never own an LPG car ever again and I have driven several, from Prins kits, with high end jets running big power, to V8's running Zavoli kits that shouldn't be on the car and BRC kits that are well suited to a car, well installed running perfectly. But EVEN IF a car has the perfect kit, it will not run as nicely on LPG as it does on petrol, it just won't.

Then why buy so many cars with it on? And you can't judge it on kits you say shouldn't have been fitted.

There will also be a power difference

Always? http://www.touringcartimes.com/article.php?id=4782

Also remember petrol is only a push button away............

That said my kit allows you to turn back to petrol above a certain RPM, so if you set a switch back to LPG delay when striping through the gears first time you hit your selected RPM you can go petrol if you wish and have it not change back until you have finished going through the gears.

Of course most of the time you only use part throttle so just push it down a little more.

All I am trying to do is give you a non bias view.

Well you said you won't own another, not you won't own another unless they improve so that's kinda bias

 

£800 for an LPG conversion??

LPG Conversion cost and LPG Servicing Prices « « LPG Conversion LPG Conversion - start at £990 plus VAT there..

Everywhere else I've read suggests costs around £1500-2000 all in..

More like prices found here: http://autogasexperts.co.uk/lpg-conversion-prices - £1449 all in on 6 pot

 

The price goes up depending on the number of cylinders.

£800 for an LPG conversion??

LPG Conversion cost and LPG Servicing Prices « « LPG Conversion LPG Conversion - start at £990 plus VAT there..

Everywhere else I've read suggests costs around £1500-2000 all in..

More like prices found here: LPG conversion Prices - LPG Gas Conversions in UK Autogas Experts - £1449 all in on 6 pot

 

Here is the explanation you requested.

Basically, I had a Stag LPG system fitted into my 535 and when it would run on LPG alone, the car would really wrestle itself to start after turning the engine off. However, when I switched to petrol for the last few minutes of a journey, there was no problem. The noise I was getting was the same as you would get if the was no fuel being pumped into the engine.

Anyway, my system was not a Prinns LPG system and I have heard that with the Prinns system, you only need a couple of minutes of petrol (as opposed to how much I used) to keep the engine sweet.

 

That doesn't back up the "dry fuel" engine wear part.

However, my kit reads the engine temperature and automatically starts on petrol and switches to gas when warm enough. Or startson gas if hot enough already. It can't switchback to petrol on shtdown as it doesn't know when you are going to turn off it just sees the ignition live go.

All it does is intercept the injector pulses and the EFI stays pressurised and ready to go at all times.

£800 for an LPG conversion??

Yes.

 

Yes I understand that, if you looked on the links the numbers quoted are for 6 cylinder engines like the OP has?

 

hi guys more food for thought!!!!
i think them prices your showing are fitted prices as ive seen them myself when browsing through sites but im looking at spending around £500 for a kit that i'll fit myself saving the labour!
ive driven a petrol ford yrs ago back in the mid nineties when it was fairly rare and to be honest i dont remember noticing any difference and i presume that would have been the old kits and not one of these sequential kits which are supposed to be better and more reliable?
im not really a racer so i only want it for cruising about but am concerned with possible starting probs after running on gas?
i was looking at your sig based on august 2011 prices and your mpg calculations compared to diesel,i imagine its even better cost wise isnt it with the current fuel prices,has lpg gone up in with petrol and diesel prices?

 

FYI, if by sequential kit, you mean switches over to petrol when you put your foot down, they are cheap kits that will damage both the LPG components and your engine, don't touch them with a barge pole. I'm sure that even E36coupe would agree on that

 

FYI, if by sequential kit, you mean switches over to petrol when you put your foot down, they are cheap kits that will damage both the LPG components and your engine, don't touch them with a barge pole. I'm sure that even E36coupe would agree on that

Just like when car efi went from firing injectors twice per revolution to using cam sensors and firing sequentially a sequential kit operates the solenoids separately.

My kit can be set to switch to petrol ar any RPM I like......... but it doesn't have to be and it isn't. Above 340 BHP just add another output to the reducer (says the label on it) and my solenoids come with two restrictor choices depending on BHP. It's running the middle size for the 328.

 

hi mate,i thought the sequential kits where the latest ecu controlled ones as opposed to the old venturi kits?
you sound like your talking from a bad experience with lpg? can i ask what kit you had that didnt seem to work for you?
ps could you recommend a decent kit??

 

To be honest matey, like I say, I have driven both good and bad kits, the one on my EVo simply couldn't cope with the power, I tuned my EVO and when I sold it, was running 450bhp on 4 cylinders, too much for any LPG kit, so even though it was a standalone system, uprated to PRINS then changed to switchover at high boost, it still couldn't feed LPG in fast enough to cope... Everything has limitations.

However as mentioned in my previous posts, BMW cars make good donors due to having 6 cylinders, therefor needing less flow rate. As for make I would go for the Prins VSi kit, it may be more expensive, but you can get the pipes, filler, valves, etc cheaper most places even eBay. However the ECU, Filter, Injectors etc. I wouldn't have anything else. Like I say there is a 320 touring in the family, that has a Prins kit, been fitted 10+ years and runs sweet as a nut, the sequential kits you are talking about then, are when as one petrol injector takes off the LPG injector takes over 1,2,3 etc? This is as the Prins VSi kit, sorry thought you meant sequential as in power lol...

If you plan on doing it, shouldn't be too hard to fit, you sound competent, I think you would just need a certified fitter to confirm it's safe for MOT/Insurance, but i'm not sure in honesty as haven't owned one for a few years. I wouldn't have another due to not running the same on gas as petrol, plus it knackered the valve seats running dry fuel... I tried Diesel 2 years ago and wouldn't have a petrol as a primary car again lol... Hence the 330D, BUT each to their own... Sorry for the essay lol, I do know quite a bit due to research, so happy to help as much as I can

 

What I am saying is, I wouldn't own one, as I don't like the issues associated with LPG. I would prefer a diesel. This is preference not bias.

Bias is implied and associated due to the language, and defensiveness on your part, I wasn't launching an attack and believe that you think your correct in what you are saying, however by mere defensiveness through your words the bias is present. Please don't think this was or is an attack by myself it is not.

As stated I have driven a fair few, not owned, driven. I owned 1, maybe 2 of the top of my head. We just have a few in the family. As mentioned, my Grandfather-in-law has a kit, Prins, fitted for 10 years, but works fine and does the job.

Please don't take this as a personal assault, or argument, it's about giving un-bias information to the OP, something that I am trying to do. You can Google Search, use references and quotations, websites etc, to support either argument. I do this as part of my research regularly, albeit from more accurate Primary and Secondary sources, but the theory is the same, however it won't give accurate information, merely other peoples representations of facts based on their positive or negative bias. Yes I will have some bias, however think I can offer advice with an objective viewpoint. Hence myself avoiding a barrage of quotations.

One thing I would advise though and any LPG installer worth his salt would too, any kit that switches over at certain rpm, can't cope with the power of the car, the reason it switches is limitations in flow, being unable to deliver the demand the engine needs, thus having to go to petrol, this, whilst under load, is not good.

 

Please don't take this as a personal assault, or argument, it's about giving un-bias information to the OP,

Don't worry, I don't, I just try and debate the points as best I can, and I tend to be quite literal so I tend to work out the numbers and go from there. :thumbsup

 

hi cbr bike cheers for replying back again!!
im really enjoying you two putting your points across,i do agree with e36coupe though about running that evo on lpg,maybe it was a bit too much for that car whereas im just looking to put on a basic 330i family car! i bet that evo shifted!!
i'll definately look at the prins kiy but regarding the sequential kits,am i right in thinking they are the decent latest lpg technology kits as opposed to the old lpg kits with no ecus? you got me confused after saying the sequential where to be avoided as i thought they where the kits to go for?

 

To answer the above issues about lubrication, you can buy an LPG lubrication system that directly lubricates where you need it, thereby avoiding the issue. Prins do a kit, it's around £80 I believe and will solve the issue. High end quality kits come with them as standard.