Discussion
I have just LPG converted another Monaro, same year and same colour!
Not much point posting any pics of this one, the install is exactly the same as the previous conversion that I posted pics of above.
The owner of this latest Monaro saw the pics of the last Monaro conversion I posted on this forum thread and wanted his converting exactly the same. He is Romanian but living in Essex and working in London. Like the previous Monaro owner, he also wanted the filler low and central at the back of the car, to both avoid any holes being made in the car for the filler and to allow filling from either side of the vehicle (can avoid having to wait for an LPG pump to be free at the forecourt - and allows a much faster fill than a fill point fitted behind the petrol fill door). Again like the other Monaro owner, he didn't want the car to use any petrol when he put his foot down - the components fitted are on top of the job so do allow that.. (unlike other Monaro installs I have seen!).
Owner reports the car is running great. He also had me supply adaptors for the various countries he will pass through when he drives the car back to Romania in a couple of months.
Simon
Not much point posting any pics of this one, the install is exactly the same as the previous conversion that I posted pics of above.
The owner of this latest Monaro saw the pics of the last Monaro conversion I posted on this forum thread and wanted his converting exactly the same. He is Romanian but living in Essex and working in London. Like the previous Monaro owner, he also wanted the filler low and central at the back of the car, to both avoid any holes being made in the car for the filler and to allow filling from either side of the vehicle (can avoid having to wait for an LPG pump to be free at the forecourt - and allows a much faster fill than a fill point fitted behind the petrol fill door). Again like the other Monaro owner, he didn't want the car to use any petrol when he put his foot down - the components fitted are on top of the job so do allow that.. (unlike other Monaro installs I have seen!).
Owner reports the car is running great. He also had me supply adaptors for the various countries he will pass through when he drives the car back to Romania in a couple of months.
Simon
aalveris said:
Nice write up Simon,car runs great,I get around 200 miles out of a tank of lpg and it's costing me 30 quit to fill it up,so not bad at all.
Replying on an old thread I know but hope you're still around.. £30 for 200 miles in a 5plus litre V8 sports car isn't bad going at all.I've converted a few more Monaro's since I converted yours and the other one on this thread.
Not long after I converted yours I converted a Merc CL65 AMG (6 litre V12 twin turbo), uprated from the standard 630bhp with a full stainless straight through exhaust system and more boost pressure to nearly 1000bhp and with a full wide bodykit to make it look the part. The car has the widest tyres I have ever seen filling out the wide bodykit! It runs totally on LPG even flat out and has been derestricted from the usual Merc 155mph speed limit so is capable of well in excess of 200mph. Yet running on LPG it costs about as much to run as an average Ford Focus.
mfp4073 said:
I'm not an expert on LPG, but are there any updated kits coming out that would be easier to install and not take up as much space.
Some of the more recent ECU's, reducers and injectors are much smaller than older types. Particularly in the case of ECUs and injectors the smaller size doesn't mean less performance, actually the opposite is often true with some of the smaller ones also being among the best performers. Comparatively small size reducers are available that are supposedly good for 350bhp but for high power applications a reducer somewhere in physical size between the smallest reducers and old type reducers are often the best bet. It is possible to fit more than one reducer, which can be handy if fitting two small reducers would make for a neater way (or even only way possible) of getting a great enough supply of gas to injectors in a very tight engine bay. Smaller size of components can mean both easier fitting and more technically correct fitting because they can allow shorter pipe runs between such as the manifold port runners and the injectors themselves, and/or allow the ECU / reducer to be fitted in a better position. There is just as much wiring etc to do as there ever was and because car engines are becoming more complicated at the same time as LPG parts advance it wouldn't really be true to say it's easier now with the newer components than it was before. Some of the more recent ECUs have features which on the face of it should mean easier calibration for an amateur but such features don't make up for a proper job of calibration by a good pro.
SimonYorkshire said:
Some of the more recent ECU's, reducers and injectors are much smaller than older types. Particularly in the case of ECUs and injectors the smaller size doesn't mean less performance, actually the opposite is often true with some of the smaller ones also being among the best performers. Comparatively small size reducers are available that are supposedly good for 350bhp but for high power applications a reducer somewhere in physical size between the smallest reducers and old type reducers are often the best bet. It is possible to fit more than one reducer, which can be handy if fitting two small reducers would make for a neater way (or even only way possible) of getting a great enough supply of gas to injectors in a very tight engine bay.
Smaller size of components can mean both easier fitting and more technically correct fitting because they can allow shorter pipe runs between such as the manifold port runners and the injectors themselves, and/or allow the ECU / reducer to be fitted in a better position. There is just as much wiring etc to do as there ever was and because car engines are becoming more complicated at the same time as LPG parts advance it wouldn't really be true to say it's easier now with the newer components than it was before. Some of the more recent ECUs have features which on the face of it should mean easier calibration for an amateur but such features don't make up for a proper job of calibration by a good pro.
OK, thanks for that.Smaller size of components can mean both easier fitting and more technically correct fitting because they can allow shorter pipe runs between such as the manifold port runners and the injectors themselves, and/or allow the ECU / reducer to be fitted in a better position. There is just as much wiring etc to do as there ever was and because car engines are becoming more complicated at the same time as LPG parts advance it wouldn't really be true to say it's easier now with the newer components than it was before. Some of the more recent ECUs have features which on the face of it should mean easier calibration for an amateur but such features don't make up for a proper job of calibration by a good pro.
There are a lot of things to consider with LPG. I have to say this is a very interesting topic.
John
maccavvy said:
more than welcome for a spin in mine to compare /figure out.. youll not say no though
How do mate! Been a while since I converted yours now isn't it (when was it again)? How much do you reckon you've saved in fuel costs since I converted it? Nice to 'see you around' again!
Cheers,
Simon
ill be seeing you the beginning of year for a service mate.
its been over 3 years now mate.... everyone is impressed with the face you cant tell which fuel its on .
I didn't note the exact mileage but ive easy done 25k so a rough guess is 2.5k-3k savings
so paid for itself and nearly double
its been over 3 years now mate.... everyone is impressed with the face you cant tell which fuel its on .
I didn't note the exact mileage but ive easy done 25k so a rough guess is 2.5k-3k savings
so paid for itself and nearly double
SimonYorkshire said:
Some of the more recent ECU's, reducers and injectors are much smaller than older types. Particularly in the case of ECUs and injectors the smaller size doesn't mean less performance, actually the opposite is often true with some of the smaller ones also being among the best performers. Comparatively small size reducers are available that are supposedly good for 350bhp but for high power applications a reducer somewhere in physical size between the smallest reducers and old type reducers are often the best bet. It is possible to fit more than one reducer, which can be handy if fitting two small reducers would make for a neater way (or even only way possible) of getting a great enough supply of gas to injectors in a very tight engine bay.
Smaller size of components can mean both easier fitting and more technically correct fitting because they can allow shorter pipe runs between such as the manifold port runners and the injectors themselves, and/or allow the ECU / reducer to be fitted in a better position. There is just as much wiring etc to do as there ever was and because car engines are becoming more complicated at the same time as LPG parts advance it wouldn't really be true to say it's easier now with the newer components than it was before. Some of the more recent ECUs have features which on the face of it should mean easier calibration for an amateur but such features don't make up for a proper job of calibration by a good pro.
Which of the injectors and ECU's do you recommend? I'm looking to convert my E46 330i so would be interested to know what you'd recommend for a 231bhp 6cyl engine. I've heard Kehin injectors are good, but Hana and LPGTech ones look a similar package for a lot less money! Our last car (L322 Range Rover with the M62 engine) was running on a King ECU and I think OMVL injectors. The calibration on it was impeccable, you couldn't detect it switching over, ever. Smaller size of components can mean both easier fitting and more technically correct fitting because they can allow shorter pipe runs between such as the manifold port runners and the injectors themselves, and/or allow the ECU / reducer to be fitted in a better position. There is just as much wiring etc to do as there ever was and because car engines are becoming more complicated at the same time as LPG parts advance it wouldn't really be true to say it's easier now with the newer components than it was before. Some of the more recent ECUs have features which on the face of it should mean easier calibration for an amateur but such features don't make up for a proper job of calibration by a good pro.
maccavvy said:
ill be seeing you the beginning of year for a service mate.
its been over 3 years now mate.... everyone is impressed with the face you cant tell which fuel its on .
I didn't note the exact mileage but ive easy done 25k so a rough guess is 2.5k-3k savings
so paid for itself and nearly double
Hi Mac, its been over 3 years now mate.... everyone is impressed with the face you cant tell which fuel its on .
I didn't note the exact mileage but ive easy done 25k so a rough guess is 2.5k-3k savings
so paid for itself and nearly double
Nice one mate! Yeh just get in touch near when you're nearly ready for the service.
Sorry the late reply.
Cheers,
Simon
ndg said:
SimonYorkshire said:
Some of the more recent ECU's, reducers and injectors are much smaller than older types. Particularly in the case of ECUs and injectors the smaller size doesn't mean less performance, actually the opposite is often true with some of the smaller ones also being among the best performers. Comparatively small size reducers are available that are supposedly good for 350bhp but for high power applications a reducer somewhere in physical size between the smallest reducers and old type reducers are often the best bet. It is possible to fit more than one reducer, which can be handy if fitting two small reducers would make for a neater way (or even only way possible) of getting a great enough supply of gas to injectors in a very tight engine bay.
Smaller size of components can mean both easier fitting and more technically correct fitting because they can allow shorter pipe runs between such as the manifold port runners and the injectors themselves, and/or allow the ECU / reducer to be fitted in a better position. There is just as much wiring etc to do as there ever was and because car engines are becoming more complicated at the same time as LPG parts advance it wouldn't really be true to say it's easier now with the newer components than it was before. Some of the more recent ECUs have features which on the face of it should mean easier calibration for an amateur but such features don't make up for a proper job of calibration by a good pro.
Which of the injectors and ECU's do you recommend? I'm looking to convert my E46 330i so would be interested to know what you'd recommend for a 231bhp 6cyl engine. I've heard Kehin injectors are good, but Hana and LPGTech ones look a similar package for a lot less money! Our last car (L322 Range Rover with the M62 engine) was running on a King ECU and I think OMVL injectors. The calibration on it was impeccable, you couldn't detect it switching over, ever. Smaller size of components can mean both easier fitting and more technically correct fitting because they can allow shorter pipe runs between such as the manifold port runners and the injectors themselves, and/or allow the ECU / reducer to be fitted in a better position. There is just as much wiring etc to do as there ever was and because car engines are becoming more complicated at the same time as LPG parts advance it wouldn't really be true to say it's easier now with the newer components than it was before. Some of the more recent ECUs have features which on the face of it should mean easier calibration for an amateur but such features don't make up for a proper job of calibration by a good pro.
Compensation for manifold pressure itself isn't of direct benefit for this engine, but it is very much a great indirect benefit for this engine because the engine's petrol pressure isn't relative to manifold pressure (as is the case on most vehicles), instead petrol pressure is relative to atmosphere (if you follow the pipe from the mechanical fuel pressure reg on this engine it doesn't go to manifold vac, it goes to the air filter). This implies that as manifold pressure increases, petrol pressure (relative to manifold pressure) decreases, yet the LPG system pressure will (at least for best results) itself be relative to manifold pressure and the LPG system map will (usually) rely on petrol pressure being (similarly to LPG pressure) relative to manifold pressure... If we pulsed a petrol injector for 5ms with 3bar fuel pressure relative to manifold pressure we'd get the same total flow of petrol through the injector in 5ms regardless of manifold pressure but if we pulsed a petrol injector for 5ms with 3 bar fuel pressure relative to atmospheric pressure the total flow of fuel through the injector in the 5ms would depend on manifold pressure (more fuel flow at lower manifold pressures and less fuel flow at higher manifold pressures) - Most LPG ECU's (including King / AEB) can only calculate LPG injector pulse length on the basis of the petrol injector pulse length, they cannot compensate fuelling for manifold pressure. If we don't compensate to correct for the relative drop in petrol pressure as manifold pressure increases we end up with a strange shaped LPG map (and then in the case of most mediocre installers they'll be wondering why the LPG map on these engines seems to have to be such a strange shape!). Even if the installer realises that the map has to be the strange shape and correctly sets up the strange shape map, it could never be quite correct over the engine's entire rpm range without addressing the fuel pressure (relative to atmosphere / relative to manifold vacuum) points (this is related to the fact the engine breathes differently at different rpms due to charge trapping capability of the cam/valvetrain, i.e. volumetric efficiency at specific rpms). I don't know of any other installer who has addressed the none manifold referenced petrol pressure issue on these engines... which will be why on most LPG converted BMW 6's of this sort of year we see fuel trims all over the place and/or strange things happening with mixture during acceleration. But if we (or I) correctly dial in manifold pressure compensation in Nevo we end up with a map shape that looks just about totally normal, and the map shape is (as it should be) correct regardless of rpm. In this paragraph I use the term 'indirect compensation' because compensating for manifold pressure on an engine with petrol pressure that is relative to atmosphere rather than to manifold pressure is the exact opposite of compensating for fuel (petrol) pressure.. We can't read petrol pressure but we know what it is on these engines (and it is a constant but relative to atmosphere instead of relative to manifold pressure), so by compensating for manifold pressure instead we can compensate the changing petrol pressure relative to manifold pressure.
Keihin injectors are good but are stupidly expensive, they also have the disadvantages of being physically too large to allow mounting in a neat position, which then has the knock on effect of not allowing pipe lengths to be kept as short as with most other injectors (long pipe lengths are a negative for performance regardless of spec of injectors so an injector that can't be mounted in the ideal spot because of it's sheer size starts with that disadvantage regardless of it's on paper spec). Hana's are good but not as good as the hype that they seem to attract, in my book they're around on a par with OMVL injectors in terms of performance (open/close time, flow rate) and longevity, which is a good thing to say in itself.. and they can work ideal on most installs, but for the utmost in accurate fuelling at short pulse times (that should be seen on these engines due to petrol pressure relative to manifold pressure being relatively high near idle) faster opening/closing injectors (in the real world.. don't go on on-paper specs or you'll be buying the hype) some of the best performing injectors are MJ injectors. MJ's also have the advantage of being physically smaller than most injectors and I find them ideal for use on BMW 6 cylinder engines. It is even possible (if we get rid of the rectangular tray like petrol rail cover) to mount MJ's pointing downhill directly above the petrol rail and run very short pipes from the MJ's, I did this on a recent BMW 6 pot I converted. But it's not just about what components are installed, it's just as much about how they are installed, setup (pipe runs, nozzle sizes, working pressures, manifold nozzle locations and calibrated as what components are fitted. If I provided an ideal list of components for a particular vehicle which someone else went on to fit, chances are I could get better results fitting less ideal components... but of course could do better again fitting the ideal components.
The pressure compensation ability of Nevo really comes into it's own when we start talking Valvetronic engines, but even on certain year none-Valvetronic BMW 6pots or any other engine that has none manifold vacuum reference petrol pressure the ability is still a very distinct advantage. And incidentally... ticking the 'Valvetronic' box on most ECU's simply doesn't cut it in terms of correct compensation for relative fuel pressure, but Nevo's compensation abilities can do a very thorough job of proper compensation.
Edited by SimonYorkshire on Thursday 14th December 19:19
ndg said:
Interesting that the M54 fuel pressure isn't manifold referenced.
If the petrol supply is ambient referenced, is there a reason that the gas system can't also be ambient referenced? Surely this would keep the LPG and petrol systems in line and give a 'flat' map?
Yes there are a few good reasons the LPG pressure can't also be ambient referenced.. In short, it's because petrol pressure is different (much higher) than LPG vapour pressure. Say petrol pressure is at 4 bar, LPG pressure couldn't approach 4 bar because LPG injectors won't work at 4 bar and because LPG could (in really cold conditions) remain a liquid at 4 bar. Also, if petrol pressure is 4 bar and manifold pressure is 0.3 bar at idle then relative pressure becomes 3.7 bar, or if the engine is driven flat out manifold pressure becomes 1 bar so relative pressure becomes 3 bar - petrol pressure thus fluctuates between 3.7 and 3 bar. If LPG pressure is set to a relatively high pressure above ambient, say 1.8 bar, then relative LPG pressure range fluctuates between 1.8 bar (flat out) and 2.5 bar (idle)... Petrol pressure fluctuates between 3 and 3.7 bar (23% range), LPG pressure fluctuates between 1.8 and 2.5 bar (nearly 40% range)... 40%-23% Is a 27% difference, which is worse than the 23% difference that would be present if LPG pressure was referenced to manifold vacuum. Not only that but for the LPG injectors to flow enough gas for top end power we might need that 1.8 bar pressure but then pressure at idle being 2.5 bar could easily push LPG injectors to have to work below the minimum pulse duration ability. If the petrol supply is ambient referenced, is there a reason that the gas system can't also be ambient referenced? Surely this would keep the LPG and petrol systems in line and give a 'flat' map?
Edited by SimonYorkshire on Friday 15th December 14:44
Make sense to give the LPG injectors a helping hand at keeping in the linear region.
One other thing is been wondering about was the whole OBD connection thing. I can see the advantage of being able to adapt the map corrections on the fly, but do the LPG ECU trims not end up fighting the petrol ECU trims?
One other thing is been wondering about was the whole OBD connection thing. I can see the advantage of being able to adapt the map corrections on the fly, but do the LPG ECU trims not end up fighting the petrol ECU trims?
ndg said:
Make sense to give the LPG injectors a helping hand at keeping in the linear region.
One other thing is been wondering about was the whole OBD connection thing. I can see the advantage of being able to adapt the map corrections on the fly, but do the LPG ECU trims not end up fighting the petrol ECU trims?
Getting the injectors to operate within the range in which they can work properly at all in many cases...One other thing is been wondering about was the whole OBD connection thing. I can see the advantage of being able to adapt the map corrections on the fly, but do the LPG ECU trims not end up fighting the petrol ECU trims?
I don't think it'd be true to say LPG OBD correction based on petrol fuel trims fights against petrol fuel trims (*although this can happen as I'll explain below) because such LPG OBD correction works in the same direction as petrol fuel trims. E.g. if petrol LTFT+STFT = +10% the LPG ECU will start with a correction factor of 0%, then in a few seconds add 1% (so now we'd expect petrol LTFT+STFT to equal +9%), then in another few seconds add another 1% (so now we'd expect petrol LTFT+STFT to equal +8%) and so on and so on until petrol LTFT+STFT = 0% (or some figure usually close to 0% set by the installer as the petrol fuel trim figure to aim for) .
- It can and will fight against petrol trims (at least temporarily) if the LPG map is lean at some points and rich at other points - Say petrol LTFT+STFT was +10% at idle (because LPG idle was lean due to incorrect LPG map at idle), so the LPG OBD correction slowly steered to +10% to compensate which eventually brought petrol LTFT+STFT back to 0%, but now the engine is put under load but the LPG map is also incorrect at this load point (at this load point let's say the LPG map is 5% rich)... If we didn't have the OBD compensation active at this point the fuelling on LPG would only be 5% rich, but because of the slow to change +10% of LPG OBD correction that is still being applied by the LPG ECU the mixture is now +15% too rich.. So under this condition the trims are fighting each other, however the situation is only temporary because the LPG ECU will see the now negative petrol trim and start to steer it's own trim factor towards a more negative value. But nevertheless, mixture will take more time to become correct than it would have if the OBD wasn't connected.
SimonYorkshire,
After reading you posts on Pistonheads, and seeing you know your stuff, could I ask you a few questions.
Replying is disabled on Pistonheads at moment, but shall share when available.
--NOW---
I bought an Audi 2.4l v6 125kw with BRC system installed.
Have serviced all I can, including Genius 1500 diaphragm, but injectors are unserviceable.
I recall someone, somewhere using other injectors on a BRC system, is this advisable/possible?
1.7-8 ohm so replacements wouldn’t be a problem, but am I flogging the proverbial, with using the BRC ecu?
Was planning on getting upgraded kit and fitting by self, whilst doing the timing belt, etc.
Original planned parts:
LPGTech 326 (non-obd)
Valtek 3ohms
Reuse reducer
New multivalve as old float sticking.
LPGTech Diag. cable
After reading your info I guess a revised part list would be:
KME Nevo Pro 6cyl
MagicJet 3cyl strip (45kw/cyl)
Maybe a combined cut-off/reducer like Tomasetto AT-09 Nordic (170kw)
Multivalve
KME Diag. cable
Also system has metal pipes, is it advisable to change to Faro?
One final question (sorry): Initially wanted LPi/LSi kit, but lpgshop quoted eye-watering amount.
Are the main differences:
multivalve with return line,
no pump needed (or pump integrated into multivalve)?
no reducer needed,
injectors in fuel-rail setup with return
Vialle or Prins ECU (can’t find others)
Thanks again, and I understand if you don’t want to answer.
Cheers
Leo
After reading you posts on Pistonheads, and seeing you know your stuff, could I ask you a few questions.
Replying is disabled on Pistonheads at moment, but shall share when available.
--NOW---
I bought an Audi 2.4l v6 125kw with BRC system installed.
Have serviced all I can, including Genius 1500 diaphragm, but injectors are unserviceable.
I recall someone, somewhere using other injectors on a BRC system, is this advisable/possible?
1.7-8 ohm so replacements wouldn’t be a problem, but am I flogging the proverbial, with using the BRC ecu?
Was planning on getting upgraded kit and fitting by self, whilst doing the timing belt, etc.
Original planned parts:
LPGTech 326 (non-obd)
Valtek 3ohms
Reuse reducer
New multivalve as old float sticking.
LPGTech Diag. cable
After reading your info I guess a revised part list would be:
KME Nevo Pro 6cyl
MagicJet 3cyl strip (45kw/cyl)
Maybe a combined cut-off/reducer like Tomasetto AT-09 Nordic (170kw)
Multivalve
KME Diag. cable
Also system has metal pipes, is it advisable to change to Faro?
One final question (sorry): Initially wanted LPi/LSi kit, but lpgshop quoted eye-watering amount.
Are the main differences:
multivalve with return line,
no pump needed (or pump integrated into multivalve)?
no reducer needed,
injectors in fuel-rail setup with return
Vialle or Prins ECU (can’t find others)
Thanks again, and I understand if you don’t want to answer.
Cheers
Leo
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