600h on LPG

Jake430 · October 9, 2017

Can a 600h run on lpg.

Britprius · October 9, 2017

I have been looking into this for GS450H, and there are conflicting views.

If the engine in the 600H has duel injection that is port, and direct cylinder injection as with the 450H the answer appears to be yes providing you also inject some fuel through the direct injection injectors. This is to stop the injector tips being overheated being cooled by the fuel. This means you loose much of the benefit of using LPG. It also means a much longer period before recovering the cost of conversion.

John.

Bluesman · October 9, 2017

Give Profess a ring they will tell you one way or the other. 01443812893

dendonc · October 9, 2017

6 hours ago, Jake430 said:

Can a 600h run on lpg.

Yes, as far as the drive goes its the same as petrol, there is a BUT, the but is where to get it converted, properly, the answer is Profess of Glam, S Wales, many members here got their LS400'S converted by profess S Wales including me in June 2013, since then I had done 34k miles & its been perfect, LPG is also cleaner.

Beware of other so called conversion places & avoid any London based completely, you also get a courtesy car for the day at profess.

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

Jake430 · October 10, 2017

Thanks for all the replies, I will contact the above company.

Jake430 · October 17, 2017

Contacted Profess, there is no unit for the 600H.

sorcerer · October 17, 2017

And if you want the technical explanation, here it is:

Several firms make systems to convert DI engines including AEB (OMVL / Emer), AC(Stag), KME, Prins. Most of the systems are LPG port injection and very similar to LPG port injection systems we fit on petrol port injection engines, using the same injectors, reducer, etc, except the electronics are special... electronics have to be special to interpret DI injection pulses and emulate DI injectors. Port injectors are usually pulsed only once (sequential injection) or twice (group injection) per cylinder intake cycle but DI injectors may be pulsed several times per cylinder intake cycle and the various pulses per intake cycle can be of different lengths (hence 'interpret'). DI engines may even pulse injectors during the compression stroke.

The LPG systems referred to so far involve fitting an LPG port injection system onto a petrol direct injection engine. DI engine cylinder heads are designed around the petrol DI injectors, we cannot fit a second set of DI injectors inside the cylinder head, the tips of DI injectors fire directly into the cylinder / combustion chamber. When we convert a port injected petrol engine we can fit the second set of injectors (the LPG injectors) very close to the factory petrol injectors and can achieve results that are indistinguishable from driving on petrol because the principals/methodology between port petrol injection and port LPG injection are much the same. But if we fit an LPG port injection system onto a petrol DI engine the principals/methodology isn't the same (port versus direct, single LPG injector pulse on the intake stroke versus multiple DI pulses that may occur during the intake and/or compression stroke) - So for example, the special LPG electronics have to add up the total duration of DI pulses per intake cycle to derive a pulse length for LPG port injectors / fitting port injection onto a DI engine means you lose any advantage that direct injection might give (local/pocketed correct mixture in the combustion chamber which allows di engines to run what would otherwise be a cylinder wide very lean burn) / the DI injectors must in any case still flow some fuel (petrol in this case) because the flow of fuel is what prevents the DI injectors being damaged by overheating (DI injector tips inside the combustion chamber) / so they don't run on 100% LPG even when running on LPG.

Then there are fuel shunting type systems, where either petrol or LPG is fed to the vehicle's factory fitted petrol direct injectors. The greatest challenges for manufacturers of this type of system seem to be more plumbing related rather than calibration related - Two fuels both use the same set of injectors (the vehicle's original DI injectors), so there could be potential for backflow of one type of fuel into the other type of fuel's tank via the other tank's fuel lines etc. A bit of petrol finding its way into the LPG tank might not have ill effect but a bit of LPG flowing into the petrol tank via petrol lines could be disastrous, a petrol tank cannot take LPG pressure. Some vehicles with this type of system have cold start problems if the engine was turned off when running on LPG.

Prins make both types of system (port injection and fuel shunting). Another manufacturer of the fuel shunting type system apparently went under a year or so ago, not many manufacturers make shunting systems.

The above information was found on the LPG Forum website. In its original context, it was an answer to a question posed by another forum member - it is not my work and I claim no ownership of it but thought it of interest in this topic.

dendonc · October 17, 2017

15 minutes ago, sorcerer said:

Prins make both types of system (port injection and fuel shunting)

Oh, Profess use a stag system...........

sorcerer · October 18, 2017

11 hours ago, dendonc said:

Oh, Profess use a stag system...........

Do they only use Stag or do they use other systems too?

I'm no expert by any means but when I was looking to have my first LPG conversion done many years ago, I literally spent months researching who and what was out there before entrusting my car and my hard-earned cash to an installer.

It was very much a 'catch 22' situation in those days. You may find an installer with a brilliant reputation but they were only qualified to install one system and they could not guarantee that it was the best system for my car, or you found the complete opposite in that you found the best system for the car but the installer wasn't great. It took me six months before I was confident that I'd found the right combination of reputable installer who knew his stuff and could fit the best system to suit the car.

However, much has changed in the last decade and now the technology exists to enable installers to 'mix and match' systems, picking the best individual components (say, a NEVO ECU, matched with an AEB reducer, matched with injectors from someone else as an example) to create a bespoke system that is best suited to any situation, rather than just a kit of parts from one manufacturer. Of course, it means that the installer must really be on the ball to ensure the best results but the LPG arena is very different now to when I first entered it. You still have to research things to make sure you're getting the best installation but very good places can be found (along with very bad ones too, of course, hence the need for research).

Malc · October 18, 2017

just remembering a couple of years ago, and comments on here too, that the Govt was going to find a way to " fuel tax " LPG a little more .............. I suppose much like it will with electric charging ........... there's bound to be the inevitable " fuel tax "

Malc

dendonc · October 18, 2017

Ive just sent this to Profess, but, I think Profess only install the one system and all instillation staff are sent to Poland for training (or are already there, are trained, then come here) so I >guess< they are all only trained on the one system.........

Just sent to Profess

Can you tell me which make LPG system you install or do you only install one system, if so which

sorcerer · October 18, 2017

51 minutes ago, Malc said:

just remembering a couple of years ago, and comments on here too, that the Govt was going to find a way to " fuel tax " LPG a little more .............. I suppose much like it will with electric charging ........... there's bound to be the inevitable " fuel tax "

Malc

Yes and no. LPG is unique in that most people pay for a conversion to an existing car rather than it being LPG-powered from the factory so there has to be a certain margin to make that viable. If the government slap too much tax on the gas they will kill the LPG industry stone dead in one fell swoop and I'm sure they would prefer getting some revenue in rather than none at all. If manufacturers started making cars with LPG engines in any significant numbers then yes, I'm sure they would raise the tax and duty on gas much higher, but I don't think they'll bother for now.

As for electric vehicles, yes, electricity prices will shoot up sooner rather than later, probably under the justification of having to provide charging infrastructure, as well as generation and transmission costs. Oh, and don't forget the old 'Economy 7' tariff. Overnight electricity is only cheap at the moment because not much is used during that time period - once you have a nation of electric vehicles charging overnight, it won't be cheap anymore.

dendonc · October 18, 2017

Below is the reply I got from Profess:

Thank you for your e-mail.
We service/repair almost all of the lpg systems but fit only one.
It is STAG make from www.ac.com.pl

.I notice their telephone code is Poland, so their workers must actually do an instillation course with Stag, poland branch.

sorcerer · October 19, 2017

14 hours ago, dendonc said:

Below is the reply I got from Profess:

Thank you for your e-mail.
We service/repair almost all of the lpg systems but fit only one.
It is STAG make from www.ac.com.pl

.I notice their telephone code is Poland, so their workers must actually do an instillation course with Stag, poland branch.

Thanks for that info Denis, it's interesting but also disappointing in a way. They may be the best installers in the world but there will be times when the STAG system is not the best or most appropriate one for a given application, which is the exact situation I was finding (and trying to avoid) years ago.

Given that, the OP may find that other companies / installers could indeed convert a 600h, I don't know.

Jake430 · October 21, 2017

So far I have not found any company that can convert a 600h.

Britprius · October 21, 2017

7 minutes ago, Jake430 said:

So far I have not found any company that can convert a 600h.

As in my earlier post I came across the same problem. As with sorcerer's post (John) in red it states as I did that fuel "petrol" still needs to be injected to keep the direct injectors from being destroyed making the system less viable than it normally would be. Unfortunately for the moment anyway there seems to be no way round the problem.

I am now looking into the possibility of electric assist conversion to make more use of the 186 HP electric motor fitted in the GS450H transmission. This could be along the same lines as the Prius conversions. The problem with the Prius conversion is the relatively small electric motor in the Prius "50 HP" severely limited it's performance, but no such problem with the GS. This used in blended mode would give a considerable boost to MPG figures.

John.