rangerovers.pub
The only place for a coil spring is up Zebedee's arse
Member
offline
1345 posts

Above I mentioned the P38 I'm working on at the moment. No problem regards what I'm doing with the LPG... but sat in it in the yard with my foot on the brakes there was a sudden noise from under the bonnet which then continued, sounded like a PAS pump low on fluid. Got out to check and there's a pool of brake fluid near osr wheel! Noise would be ABS unit? I was late picking the missus up after tea from her mums so haven't even been under it yet to see where the leak is from, hopefully the flex pipe. Topped up the brake fluid reservoir and the noise went as expected. I've previously read comments from I think Gilbert about just turning the ignition on and ABS unit will prime the rear brakes, comments welcome in case it lands on me to sort this aspect out! How soon will ABS unit fail with lack of fluid to that corner, say should the owner decide to risk driving it away to repair elsewhere? How much of a bugger is routing new copper pipe in case it's the main pipe that's failed? Sods law this is gonna land on me over yet another weekend!

I realise I should maybe have started a new thread or posted this on a more relevant thread, might do that myself or won't mind if mods do it.

Simon

720mm diameter x 270mm height are the biggest dimensions that will fit while keeping the boot floor flat at the original height. Tank of those dimensions will be around 93L with side exit or 85L with middle exit, you should be able to fill to 80% of those capacities with LPG or 90% if the tank valve float arm is bent a bit. There is also a '4 hole' tank option, where the pipes can enter / exit the vehicle in just about any position you wish but they are more expensive and typically hold a couple of litres of gas less than the side exit full toroidal type.

I am very close to Frickley off-roading centre (otherwise known as Frickley pit tip) and have converted quite a few 4x4s including P38s that frequent the place. Like Gilbert said there will be no problem off-roading, and if you should ever roll an LPG converted vehicle the LPGl can't escape.

Working on a P38 at the moment, removing it's Piro LPG ECU and fitting a King, which involves changing the LPG wiring loom and interior switch, then we'll see how well the 10+ year old injectors and reducer work... parts have got better since then.

Simon

Got to be easier when you've done it many times, can also pick up a lot of insight into what's going on. I don't much get involved in fixing any others aspects of cars other than LPG installs and engine management / fuel injection problems but concentrating on those aspects will have concentrated my skills on those aspects. I'm not bad at general mechanical stuff but my mates who run garages in the area are far more likely to know all the ins and outs of most usual type mechanical jobs for a random model of vehicle than I am... I recently ummed and ahhed whether to change my son's Mondeo clutch myself (son helping) or to stick to what I do best and let mates garage change his clutch. We bought all the bits, or so we thought, then decided on letting mates garage fit them, mostly because I was too busy with LPG work. The garage said 'Ooh I'd really rather change the hydraulic release arm at the same time, when the clutch is nearly worn out the arm can in effect get stuck at the full extent of it's movement, or even if it isn't stuck it may fail soon due to being worked at the full extent of movement. Mondeo's subframes have to be lower to change the clutch and the bolts are often seized, it may involve some cutting and welding of the subframe'. We bought the arm and had him fit it at same time as the clutch, turned out he did have to cut and weld the subframe - I could still have done it all but was pleased we let him do it. If my mate at the garage were to fit his own LPG system I doubt he'd second guess me but if he did I would liken the situation to role reversal but where I decided to crack on and not change the hydraulic clutch arm and not anticipate the problems with subframe... and I could be oblivious to the pending failure of the arm until it failed.

Fuel trims will always bounce about just + and - of 0, they're supposed to do that as management never reaches a steady state, it is designed to flick lambda slightly rich and slightly lean constantly, on engines that meet usual OBD2 standards with narrow band probes the stft will always flick at least around +-0.8%. Calorific value of fuel doesn't effect calibration, if the engine doesn't make as much power due to lower cv the driver simply puts his foot down more so pinj increases to match... stochiometric ratio does effect calibration but would result in lower ginj than pinj, though the difference between 14.7:1 and 15.4:1 is only 5% and petrol trims could cope with this easily. The difference between petrol injector and LPG injector properties is the biggest reason we need an LPG ECU at all, followed by need to more accurately account for fluctuating density of fuel (pressure and temperature, due to LPG being a vapour not a liquid, which again is why we can't use petrol injectors for vapour LPG). In some respects it could all be easier for direct injection engines - supply the di injectors with LPG at the same pressure as petrol and an LPG ECU isn't strictly necessary because no calibration is necessary.

Engines running on petrol are far more likely to deliver more power with a rich mixture than engines running on LPG, you don't get the charge cooling (charge density increasing) effect from injecting vapour LPG and the LPG vapour takes up more of the volume of airlfow, so you lose volumetric efficiency. It is safer for the engine to go too rich rather than too lean but max power will usually occur a bit leaner than on petrol, implications of which will effect fuel consumption while booting it. Closed loop single point LPG mixer systems generally aim for about 0.75v lambda 4000rpm+ with wide throttle where petrol lambda reading would max out at 0.9v because petrol mixture would be a lot richer than the probe could measure. Some of the NecamKoltec engines continue to aim for stochiometric (0.5v) lambda even during flat out conditions and f they make any less power on LPG because of this it is negligible.

All AEB ECU's have temperature correction which can be adjusted in software settings if software allows it. To access those settings you need the correct dongle, dongles were originally parallel port types but later on USB types became available. I have a range of dongles for different AEB systems, they also allow you to make changes to the full map in pre V6 versions of software, set the ECU to start on gas everytime even with a cold engine (in case of monofuel i.e. no petrol tank even fitted), adjust lambda emulation waveform on the grey lambda wires (aka AEB175s), etc etc. You can probably do more with V5 software than with V6 if you have the correct dongle. I have been known to bring an old desktop PC outside with a parallel port dongle attached to access those settings on an older ECU, even run the desktop and monitor from an invertor to calibrate lol.

If LPG calibration is rich petrol trims will of course go negative, and then if engine management applies trims during cranking it can lead to problematic starting.

Simon

If you're happy it runs properly on petrol, lambda flicking well and going rich during high load open loop operation, all you've got to do is match pinj while running on gas to pinj when running on petrol - then fuel trims will be the same under all circumstances as they are on petrol. P38s are particularly easy to achieve this on even without looking at fuel trims, but fuel trims can be used to confirm.

There are a few schools of though on calibration - 1 calibrate so trims are close to zero on LPG, but I'd only do that if trims were close to zero on petrol or on specific models of vehicle such as a supercharged L322's / 2 aim for trims to be the same as on petrol (which is what I just suggested above, and I'd only do that usually if petrol trims were reasonable i.e. not sailing close to being minned/maxed out), / 3 aim for trims somewhere between zero and petrol trims.

Many older vehicles only have one ltft, as vehicles get newer they tend to have more and more ltft;s each covering a specific range of rpm versus airflow (or map or less commonly TPS). Some have a different set of trims for different coolant temperatures. On some there is an underlying trim for idle before ltft is even applied which is learned on the basis of something like average trim for off-idle conditions (e.g. BMW). BMW's even have a trim for each individual cylinder called 'smooth running.value'. Out of all the Rover V8 engine'd vehicles I've worked on regards LPG, as memory serves only the late model Rover engine'd D|isco's with EGR have fuel trims which are much like the norm but they are all a low demand engine and very forgiving regards fuel trims and LPG calibration.

It is quite usual for installers such as myself, Dai and Andy to calibrate a system to be close to petrol trims, steering slightly to the side of zero, until the engine goes open loop and then our maps go a bit leaner.if we want more power on an engine that runs enough ignition advance because in this case there is no advantage to high load enrichment when running on LPG which would only start to impart on volumetric efficiency (especially on turbo vehicles with chipped woefully rich maps), or the same mixture if not quite enough advance (for LPG) means running a lean mixture would degrade power due to slower burn and overheat the valves, or a bit richer mixture if it is an engine with soft valves to protect the valves.

The default temp compensation values in AEB are exaggerated, you only really want a range of about 12% from 0c to 60c with zero comp at around 40c. Hardly any systems except AEB compensate for reducer temperature by default and on vehicles with AEB where under bonnet heat doesn't affect gas vapour temp readings I zero all reducer temp related compensation... but it can be handy on installs where under bonnet heat does incorrectly affect vapour temp readings.

It can be best not to obsess about trims on P38s, far better to get ginj suitably above pinj by selecting suitable pressure and nozzle size. Smaller nozzle with higher pressure, and the opposite, can do much the same thing when you get away from idle but at idle things work a bit differently, and Boyle's law works perfectly for an ideal gas but LPG apparently isn't an ideal gas, and you don't need as much relative pressure when manifold pressure is higher.. .

Got a P38 coming in for at least a new ECU on Thursday, and since it currently has a Piro fitted it will also at least need a new loom... but I'll have it calibrated about as good as it could within about 10 mins of changing components without using a Nanocom ;-) I'v e just converted about 10 Nissan Elgrands almost back to back, mostly 3.5L E51's but some 3.3L E50's, my first guess on pressure, shape of map and map levels was almost spot on. Nearly finished conversion of an Elgrand E51 2.5L, and dare say my first guess on pressure and map will be just about spot on for that too! ;-)

Simon

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

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

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

I'm not at all familiar with Nanocom but going on what you've said it's fuel trim readings seem similar in concept to Jap import stuff where 100% Alpha would equate to Euro ltft=stft = 0, one of your trims at 1.50 might equate to Alpha 150% or ltft=sftf = 50%. I'm converting a lot of Jap import stuff these days!

Using the scope in software would have to be done at the same time as monitoring trims, because during proper closed loop operation ginj will remain the same when you adjust calibration while pinj figures change.. Suppose If trims were highly negative, then for a given pressure and nozzle size ginj might be suitably higher than pinj but only because of the negative trims, if calibration were then adjusted to bring trims close to zero ginj might be below pinj... Got to compare ginj with pinj when trims are about right to know if pressure and nozzle combination are about right, though tbh it won't make a great deal of difference on a P38 if ginj is a bit below pinj, all it will do is momentarily slightly richen mixture during positive throttle movements. The switching method can be used instead of the trims method, I use a combination of trims monitoring and switching method during the same run.

Simon

Hehe, It is for reasons like this that I tend to be a bit over-explanatory.

Won't hurt to try the 4k7 setting mate..

All coming back to me now about your ex Zavoli P38 install on the other thread - I sometimes forget due to seeing so many cars and talking LPG so much!

Next question following post above might have been how does ginj compare to pinj when you put your foot down and mixture is suitably rich?

Simon

@OB, Just out of interest do you go to Glastonbury as a punter or more involved?

What temp readings are you getting now? I think the default 4.7K setting should work.

It is normal for the changeover switch not to light the first few times you turn ignition on if the ECU hasn't been calibrated, it usually stays lit while ignition is on after then if firmware is new enough to have the rpm box unticked by default, yours should be like this. Another strange aspect of AEB ECUs is that there can be a bit of misfiring on petrol the first time the engine is started with a new ECU fitted that hasn't been powered up before, can only put this down to ECU not making the connection across the petrol injector loom break at that point for some reason.

What nozzles did you fit in the Hana's? Hana's selected in firmware? Using a Zavoli reducer at 1.4 bar?

Simon

I've only just noticed this thread...

Most AEB system temp sensors are the same spec except Tartarini.

King ECU with latest software and that firmware allows you to select between a couple of temp sensor specs for both reducer and vapour...

Yes the later ECUs won't show current data with ignition off. Some won't show current data if the interior switch is broke either.

If temps were incorrectly reading 110c it wouldn't throw mixture off much during most conditions but would throw mixture off a lot if temp readings were -40c. Default temp correction goes wildly negative for -40c but is maybe only +8% for 110c.

I wouldn't connect to OBD.

SImon

I know a bloke who paints every vehicle he gets matt black and mounts a plastic skull either in the front window or on the bonnet. He was into 4x4's a couple of years ago, didn't buy it from Yorkshire did you?

Changed my signature anyway :lol: Now to see if this works...

Simon

Done the thread on the car on LPGforum Maserati

If anyone posts on that thread, no mention of the vids please ;-)

I'm certainly not a virgin mate but yeah I've been on a couple -) Sky.

I'll be doing a thread on LPG forum on a Maserati Grand Turismo I just converted, but I dunno if I'll be including the following content, or if I do it may be with a disclaimer!

Those that know me may be interested ;-)

Dropbox links 190mb and 100 mb respectively::
.
vid 1

vid 2

I thought I was the first to convert one of these, at least properly, at least to run totally on LPG at full throttle up to the red line in sport mode, so what a shame when as a coincidence I receive these anonymous mental videos via email (or something, I forget how I obtained them now) from some other at least half decent LPG pro who seems to have achieved just that. Obviously I wouldn''t be crass enough to film such stuff on phone, especially while I was driving. Man after my own heart, though... . ;-)

Simon

No probs Marty.

Yeh I thought the figures you mentioned seemed to point to bigger than 2.1 nozzles. Hanas without nozzles flow a little bit more than Hanas with 3mm nozzles, I think you'd be good with 3mm or no nozzles if you can turn pressure down a bit (1.2). Or you'd be OK with current nozzles if you could turn pressure up to 1.7 bar..

Yes the late spec P38 / Disco Bosch ECUs are more OBD2 compatible and show trims correctly (as you'll know maybe better than me) so an LPG ECU's OBD facility should read trims properly on that, but still I wouldn't advise connecting. There are pros and cons to connecting to OBD and I reckon the cons outweigh the pros on most vehicles - I hardly ever connect OBD.

Matrix setting will be best for Hana's, but the map figures with Hanas are pretty much a straight percentage so 180's in the screen represent a multiplier of 1.8 which points to too small combination of nozzles / pressure.

The problems with low resistance Hanas with AEB would apply to the King ECU too. The King may have an option for Hanas but still the AEB ECUs can have problems driving them consistently at low pulse duration, but low pulse duration isn't seen on a P38 so this won't be an issue. The reliability of AEB with Hana's isn't a big deal, among those of us with enough experience to attribute ECU failures to low resistance injectors the rate of failure noted has been very small.

Over the years Zavoli have used various types of injectors - Matix wearing Zavoli stickers, Zavoli pan type and a couple of types that are of a similar design to Valtek type 30's. I have all types here that I've removed from vehicles in the past but out of those wouldn't consider using anything other than Matrix and perhaps pan as part of any install or repair. Pan were probably the best Zavoli own brand injectors, Matrix best out of the lot, the other types would probably rate poorly to most modern injectors and the firmware settings for them would be a bad match for Hanas.

Simon

Hi Marty, Yeh I've fitted loads of Hana2002's lately on stuff like Nissan Elgrand 3.5's. Would advise at least 2.5 nozzles on the P38 (I used 3mm on the Elgrand 3.5 engine at 1.4 bar..) - You don't really want numbers above around 150 in the map, especially if you selected some types of injector such as Matrix in firmware. Wouldn't advise the LPGtech ECU, if you intend to go anything other than AEB I would suggest KME Nevo (the top version has OBD adaptivity built in), or even Stag in preference to LPGTech. You could even just buy a King ECU and swap it in, you can buy an OBD loom to add to your existing loom, you just push female pins into relevant pin holes in your existing AEB ECU connector)... But I wouldn't advise connecting OBD anyway.. even if it would read your trims properly given the P38's none standard OBD (that means some OBD readers including LPG ECU readers return trims of 99% even if trims and everything else are perfectly normal). Nearly a quid a piece for Hana Gold nozzles - just drill them out! I grip them in the round grip section of pliers in one hand and use a small chucked battery electric drill in the other, when you get the knack of it you can feel if the drill is following the existing hole, takes me about 10 seconds each nozzle.

Simon