When we got our P38 we were happy to use it as a petrol car, given the low mileage we intended to do. As our use of the car is changing I'm looking in to LPG a bit more.

But I know precious little about it.

I'm aware there's different types (single point, multi point and sequential) but I'm not really sure of the pros and cons of each. I'd guess that in terms of which was "best", they'd be ranked Single > Multi > Sequential, with a cost bump for each.

If I do go LPG, I'll be getting a wheel well tank. I know they're smaller but I'm more willing to sacrifice the spare wheel than boot space.

Beyond this, I know nothing.

I've seen a kit on eBay claiming to be complete: https://goo.gl/HK24dw.

Is this a good brand? What does it mean by "front end" parts? Is considering a second hand LPG kit madness? If so, why? Is this something that is even remotely DIY-able?

What advice would give to complete beginner with LPG?

I'd ask Lpgc for a quote. He quoted me a figure for a full and complete installation that I thought was very fair but after much consideration, I don't think I do a high enough mileage to merit it. I'm talking a mileage of 20-30 miles a WEEK on average and sometimes a lot less.

I've been doing some sums.

I think I found LPGC's website (it has the same name at least): http://www.lpgc.co.uk/index_files/Page600.htm

Fully fitted price is from £1300, DIY kit is from £814. Second hand eBay kit is £300.

Guestimated MPG's of 15 for LPG and 19 for petrol.

Break-even mileages are roughly 12,250 for fully fitted, 7,700 for the DIY kit and 2,800 for the eBay kit.

I've owned the car just under 1 year and I've done just under 6K miles for just recreational use. My mileage is jumping up to around 55 miles per day until August at which point it drop again to unknown amount. Unless I buy another car after this, the mileage will increase again.

The LPGC systems are listed as "multi point sequential" but the eBay one is just multi point, so it's not quite comparing apples with apples.

Is sequential significantly/noticeably better than regular multi point?

Are used kits from eBay not even worth considering?

I'd say your MPG figures are about right. These days "zero degree" tanks are about as big as the takes-up-your-boot cylinder - mine is 95 litres and should hold 75 litres but the way the filler valve has been set up it just clicks off at 80 litres from empty. Roughly 250 miles tank range and 50p/litre makes my 4.0 a practical daily driver. As well as being cheaper to run the emissions are a lot cleaner and the oil stays a lot cleaner.

The conversions are pretty easily DIYable by anyone handy enough with the spanners to run a P38. The biggest nightmare of fitting the old systems was running the fiddly copper pipe - new ones use plastic pipe that you could tie your boots with.

I wouldn't buy a used one from eBay because you don't know what kind of condition it's in and the tank will likely be nearly out-of-date anyway.

Out of date tank?

Do the tanks need renewing at certain intervals?

LPGC would tell you more but they're only meant to be used for ten years or something.

RutlandRover wrote:

I've been doing some sums.

I think I found LPGC's website (it has the same name at least): http://www.lpgc.co.uk/index_files/Page600.htm

Fully fitted price is from £1300, DIY kit is from £814. Second hand eBay kit is £300.

Guestimated MPG's of 15 for LPG and 19 for petrol.

Break-even mileages are roughly 12,250 for fully fitted, 7,700 for the DIY kit and 2,800 for the eBay kit.

I've owned the car just under 1 year and I've done just under 6K miles for just recreational use. My mileage is jumping up to around 55 miles per day until August at which point it drop again to unknown amount. Unless I buy another car after this, the mileage will increase again.

The LPGC systems are listed as "multi point sequential" but the eBay one is just multi point, so it's not quite comparing apples with apples.

Is sequential significantly/noticeably better than regular multi point?

Are used kits from eBay not even worth considering?

You have the right website for Simon (LPGC) there.

The kit your looking at will need at least some bits if you go the eBay route - and bear in mind its a used kit at that with no comeback if it fails a few months down the line. Tank may or may not be OK, but they do only have 10 years life if you need it certified. Injectors and vapourisers wear out, and new ones will perform better (and are cheaper to replace with new ones than trying to find older compatible ones). The kit your looking at with the manifold will need a spud removing from the manifold as its been broken, not major but thats just what i can spot from the photos to start with. You'd also want to consider replacing all the hoses etc plus supply your own run from the tank to the engine bay.

The lpg forum http://www.lpgforum.co.uk/index.php (which many of the users here are on as well) is worth a look through. Also worth a look for prices on the likes of TinleyTech and LPGshop to get an idea of prices for kits etc.

Its worth contacting Simon (I've got a kit working on my Focus from him, and another kit ready to fit to the Discovery once its got its MOT sorted) as he will be able to advise more precisely what to do and where to place stuff if you wish to do most of the work yourself. Either way it still needs calibrating/setting up, and thats where your most likely to hit problems later.

There was a few systems which were halfway between single point and sequential. Would have used a distributor arrangement to supply gas to each cylinder rather than filling the manifold with gas via a carb-like arrangement. These would be very out of date now but what your looking at on eBay just looks like an older sequential system nothing more.

RutlandRover wrote:

Out of date tank?

Do the tanks need renewing at certain intervals?

gordonjcp wrote:

LPGC would tell you more but they're only meant to be used for ten years or something.

They are supposed to be pressure tested at 10 years, the cost of doing so (and removing tank etc to do so) is supposed to outweigh the cost of replacing the tank outright. To get the installation on the drivelpg (uklpg) register it needs to be certififed, to certify it the tank should be within its test date. If your insurer requires it to be on the register this may be an issue with a used kit.

As above LPGC will probably elaborate on this point.

My experience of LPG is that if you like fidding with stuff and tend to obsess over whether probably nearly perfect can ever be quite good enough, then an LPG kit is the ideal birthday present. If you've got a car that needs to just work* then get a professional to do it.

*or someone else drives it, especially someone who isn't going to listen to lengthy theories about ambient air temp or O2 sensors.

I run a single point on mine but it is a bit low tech and not recommended for a GEMS and far too low tech for a Thor like yours. Multipoint uses, as the name suggests, an LPG injector per cylinder and can be batch fired, or sequential. They piggy back onto the petrol system so instead of firing the petrol injectors, the engine ECU fires the LPG injectors (via the LPG ECU). Some earlier systems only picked up the pulses from one cylinder per bank so effectively batch fired the LPG injectors so not true sequential (much like some earlier petrol systems, such as the Lucas 14CUX system on a Range Rover Classic, which has all petrol injectors per bank firing simultaneously). Modern systems are truly sequential so fire the individual injectors just as the petrol system does.

The problem with buying secondhand kit is that you have no idea if it was working properly when removed. The wiring loom will have been chopped about, the injectors may be worn, the reducer diaphragm may be on it's last legs and you won't get everything so you can just whack it in. You'll almost certainly find bits missing or that you can't reuse. Tanks have a certified life of 10 years as already mentioned but the main gas feed from tank to the engine bay will also need new pipe and fittings. Then there will be the little things like the nozzles for the inlet manifold and hose clips that you won't want to reuse even if they come in the box of assorted bits. So really, not worth going for unloess you like to spend a lot of time fiddling.

It is perfectly feasible to install it yourself. Plan out where you are going to fit the bits, pipe runs and the like. The only real mechanical work is drilling and tapping the inlet manifold to fit the nozzles. If you think you are going to have the time, get the kit of bits from Simon (other suppliers are available), if you think you are likely to be up to your neck in nappies in the very near future and won't have the time to do it yourself, drop it off with him and let him do it for you. Agreed, payback time will be a bit longer but you get a really nice, warm, almost conceited, feeling inside whenever you hand over a mere £35 for a tank full of fuel that is going to last you appreciably over 200 miles.

As far as I see it, multipoint and sequential are the same thing.

Multipoint systems are where you have an injector for each cylinder which is sequentially injected at the right time (IE when the petrol injector would normally fire)

As far as I was aware, the more expensive systems were Direct Injection - which is higher pressure and directly injects liquid LPG into the inlet, rather than the lower pressure gas which has been through the vapouriser/reducer.

If you are a DIY'er, then go for a kit and install it yourself... If I were doing a fresh install, I would get a brand new kit, rather than someone's old stuff. Whilst it might be cheaper to get a second hand kit, it's always going to be hit and miss, as you don't know how they've wired it, if the injectors are old/worn, and also as mentioned would need re-setting up and calibrating to your vehicle anyway - so you would also either have to take it somewhere or get the software/cable to do it yourself.

I've just been through and replaced pretty much the whole front end of my system - new injectors, pipework, filter, vapouriser - and most recently ECU as the old one (was originally installed in 2008) decided to start playing up, just as I had finished the rest of the gas install and got it calibrated again. About the only bits I haven't changed is the tank, valves, and the gas line from the wheel well to the vapouriser.

IMO, if you an get an eBay kit for cheap, then great - but don't be surprised if you have to start replacing bits of it sooner rather than later - at about 6yrs on my Zavoli system (fitted about 4yrs before I bought the RR - so a couple of years after I bought it) one of the injector wires failed, which I repaired, then another went, so decided to replace them all - which then lead to redoing pipework, filters etc. vapouriser was done when we swapped the engine as the cooling system was drained, and I figured the rubber diaphragm at 8yrs old was probably going to need replacing at some point.. I'm not saying that you won't have half of what I've done - to do to an eBay kit - but it could be a false economy if you get it cheap, and have to replace parts in a couple of years, vs buying a new kit which will last the next 8-10 yrs with just normal servicing.

I'd get in touch with Simon about a kit price if you're happy to install it yourself - or look at something like this:
LPG Shop 8 Cyl Kit

And then you would just need the tank/valve/filler etc - which you can get from LPGshop aswell, to suit where/how you want to mount the tank.

A bit more than the eBay second hand, yes - but cheaper than a full install..

My 0.02 :)

I wrote most of the following before anyone else had replied, just never clicked to post, so sorry if if it goes over the same ground as other people's replies or doesn't address some of their points.

Thanks for the mention Oldshep, got to agree you don't do anything near enough mileage to make an LPG conversion financially worth it.

RutlandRover - Don't buy that front end from Ebay. It is an old OMVL system, judging by the spud location I might even have originally fitted that system to the Rangerover the guy on Ebay removed it from! I would now expect the pictured OMVL injector rails with black coils (a very old type) to have a lot of wear on them (the new OMVL Superlight type with plastic rails and blue coils last a lot longer and are far more reliable), the reducer will have seen better days, as will the pressure sensor and ECU. The pictured parts wouldn't cost a great deal more to buy new than the old parts pictured, but all new parts would mean you would have to drill and tap your manifold (which isn't a big deal and in no way should be considered a plus point for buying second hand).

Front end parts mean just the parts that go under the bonnet, no tank, filler or any piping and wiring that run under the vehicle between the filler, tank and engine components. You would be well advised to fit new piping everywhere anyway rather than piping of that age.

Not a bad brand at all though, when I first started fitting sequential LPG systems I fitted nothing but OMVL because it had comparatively decent performing injectors and a reducer that could handle big power (far better than modern day OMVL reducers in fact) and back then front ends were bought as a complete set (ECU and loom, injectors, reducer), where these days we tend to buy individual components. The components in the second hand system are older spec than a new OMVL system though, the injectors are not as reliable and the ECU though sequential isn't truly sequential.. That's all I'll say here about sequential but not truly sequential or I'd be going into too much detail! The old ECU can give just as good results on a P38 as a new truly sequential ECU.

These days you'd have trouble buying a new front end that was mutlipoint but not sequential (but such systems do exist and were commonplace at one time... Tartarini Etagas is one example of such a system), you could easily get hold of a single point mixer system but I would only advise a multipoint sequential system.

I could sell you a complete (including tank, filler, piping, etc etc) brand new DIY kit for about £800, or you could buy the same bits from a supplier for less, but I give very detailed tech support with my DIY kits while the customer fits the system, and then the customer can bring the finished install to me and I will sort any minor problems and calibrate it properly without charging any extra. Don't forget the £800 includes the tank etc, I sell new front ends for P38s for £500. To supply and fit job done I'd be looking at £1400. To be honest I didn't join this forum with intention of making money out of being here, I'm here out of interest and won't think anything if you buy bits elsewhere etc.. Gilbert and a few other forum members could talk you through the install if you bought bits elsewhere and I would still chip in with tips and help on forum. The front end parts I'd generally supply for a P38 would be much the same as those in the LPGShop link above, though I may supply a different reducer. The reducer in the link is the modern version of OMVLS Dream unit, which (as said above) won't flow anything like the same amount of gas as the old spec Dream reducers (won't go to the same bhp level) but is capable for a P38, the old spec Dream reducer would be capable or at least just about capable for a supercharged L322!

Seems ages since I last did any major LPG work on a P38, in reality it's probably only about 5 weeks, but I've got one coming in on Thursday and will at least be removing it's OMVL Piro ECU and loom to fit a different ECU and loom. Piro was supposed to be OMVLs replacement ECU for the AEB2568 spec OMVL Dream ECU like the one being sold on Ebay (and one from LPGshop) but they never did manage to get Piro working properly and it was a short lived system, even OMVL went back to AEB2568.

Simon

Yeah, we've ruled out a used kit. Doesn't sound worth it in any way. I figured that would be to the case to start with.

That the calibration is included with your DIY kits is brilliant. I really didn't expect that. What's involved in the calibration?

Can you do the certification too? How much does that cost?

What kind of on-going maintenance is involved with an LPG set up? Looking at Marty's ECU thread. it looks like investing in some kind of diagnostics could be useful too.

I'm not against paying a bit more to cover good service :) With most things, you get what you pay for and if you know literally nothing about a subject, someone else's knowledge and experience is a valuable thing.

You'll need the appropriate software (config/ diagnostics) if you're doing a DIY install anyway. With the appropriate interface cable to a suitable laptop the software is usually available as a download with a bit of Googling.
As far as maintenance, once it's calibrated and running sweetly, just a couple of filters to change periodically and a look over all pipes and joints to check condition is all it needs.
Car will need to be running correctly on petrol (trims etc) with good leads and plugs before you do the conversion. As explained above, the LPG system takes its cues from the petrol system injector timings so if they're out for any reason, the LPG will be too.

You'd need to bring the car to me to take advantage of my free calibration. I don't include an interface cable in the prices above but can supply the proper one for around £30 (I just pass on the price to me), you might want the cable just in case you fancy a dabble yourself in future or for diagnostic purposes in future but would need one from the outset if you didn't intend on bringing the car to me for calibration.. in which case my tech support extends to talking you through calibration (but would be best if you could bring it to me for calibration). My price includes a cert I produce, it doesn't mean much but is good enough for DVLA and some insurers but not all insurers as some insurers will only offer cover if a converted vehicle is on UKLPG's database. I can register a vehicle on UKLPGs database but it costs me £80 to do so, if you want your car on UKLPGs database I just pass on the £80 to you. I make sure your install is fitted safely before I'll issue my cert or register it on UKLPG's database. If you were to buy a kit from elsewhere and wanted it on UKLPG's database you would need to take your finished install to a UKLPG registered installer for a safety check, and could expect them to charge you more than the £80 I charge only to fail it, because by failing it they may hope to charge you for 'remedial work' to 'bring it to spec'. Bit just like if your car fails an MOT on brakes.. most of us here won't have a problem sorting brakes, but if you pay the MOT man to fix brakes he's then got to pass the vehicle on the brakes aspect lol. If you bought a kit elsewhere I could still register your car on UKLPG's database but I would then also charge more than £80 to do so, though I wouldn't want to fail it and wouldn't charge more than once for inspection until it passed. At this point, if you are considering coming to me for a kit or conversion, don't mention your registration or chassis number on forum - I'm not a member of UKLPG and the information could be used by someone to discover which UKLPG members are willing to register a vehicle on UKLPGs database on my behalf, which could result in them losing membership of UKLPG. The irony is that anything I fit or approve is likely to be safer than if fitted by a UKLPG member, particularly if drive-ability is also considered a safety aspect.

Simon

Oh, yeah - I realised the calibration was your place, not at my house :)

You're only an hour and a half away so it's not a problem.

The runs great on petrol at the moment so that shouldn't be a problem.

Is the software for DIY diagnostic in the future kit specific and supplied with the kit or is it a universal type thing available elsewhere?

My post and OB's post crossed, like he says the software is free, it isn't universal because each make of LPG ECU uses specific software. I can give you the software for just about any system including of course the systems I supply / fit, and the specific software for any system I supply is available for free download from many places on the internet. I even have quite a bit of LPG software behind the scenes on my website, so can send people a link to download from my website or dropbox..

Simon

Ok, great. Thanks for all the info everyone!

Time to go home and discuss.

Spent a bit of time looking around Gilbertd's LPG installations yesterday. I think I've ruled out fitting any kind of LPG now.

I'd only be interested in a spare wheel well tank but I don't like the pipe work coming through the bottom of the well. It's too vulnerable for the offroading we do.

The pipes don't have to come out of the bottom like on both of mine, it's just that is the easiest way of doing it. If you used a hollow toroidal tank as on my white one then the pipes, cabling and vent does need to come out of the centre but with a filled toroidal the connections are on the outside of the tank so there is nothing to stop the pipes coming out of the side of the wheel well higher up. They could then run along the inside of the chassis rails (or even along the top as the petrol pipes do). The biggest advantage would be that your 52 mile a day commute to work would cost you around £7 a day (especially as you have the cheapest LPG supplier for miles less than half a mile from work).