Gas conversions

[Tweak'e]

i'll have to go find it again, i think it was an AU crowd. they where advertising a full ECU that monitored boost, TPS, engine temp, rpm etc and fully mappable. not cheap but a whole lot better than these run by boost pressure only systems.

edit: it could be the Sequent II i'm thinking of but i cannot find exactly what sensors etc it uses.

edit2 : found it ! Technical info about gas injection systems
A new feature of DieselGas Sequential II is that it actually allows gas flow at idle. For vehicles that spend a lot of time idling, a substantial amount of diesel can be saved by substituting LPG for extended idle periods. This is only possible with the accuracy offered by a vapour injector. Incidentally, this also reduces engine idle noise.

i saw a bit of info that looked like there is a scrap between a couple of companies. mmmm....two compaines with similar named systems.

[Aussie Frontier]

seems like technology has gone ahead for the diesel engines as far as gas goes but looks like bugger all new in the petrol engine conversions

[Martin from Downunder]

at that site

""An electronic control unit (ECU) controls the rate of injection, optimising performance and ensuring safety. Manifold pressure, throttle position, engine temperature, exhaust temperature and engine speed are all monitored. The ECU then adjusts the gas flow depending on engine load and driver demand. The amount of gas injected (or the ‘gas map’) is completely self learnt - the ECU adapts to your driving style. The system can be monitored and adjusted via a laptop if necessary. This allows a large degree of flexibility to adjust the system to suit your requirements.""

same with the D-gas
M/pressure (load) , temp sender, throttle and boost sensors are hooked up to there control unit, more then likely be a ECU as well.
I did have a look at the other system quite some time ago and the word that I got back was, that they had over fueling issues and some engines self -destructed Boom rattle rattle rattle $$$$
I dont know if they have fixed this on there mark2 version or not but would think that they have.
I will still go for D-Gas its a far neater set up and the figures are the same, like everything these days almost everything is the same!!!

[Tweak'e]

Is the D-GAS wired to the vehicles Ecu or sensors?

No D-GAS is a fully automatic system & only requires the following wiring to the vehicle, 12 volt live under key, negative, 1 wire to the alternator to sense running of engine.

this is what sounds suspect. you can't actually monitor throttle etc without actually tapping into it. don't know if they havn't updated site or just have a load of BS marketing.
also i think d-gas shuts off at idle.

also having an interesting thread on other forum about diesel lpg systems. some dispute as to if the lpg actually ignites before diesel is injected which may or may not be actually doing damage. instead of the lpg burning with the diesel the lpg is burning before hand and increaseing the air temp and press urein the cylinder which helps with the diesel burning. a bit like a bigger version of pilot injection.

[Martin from Downunder]

Stop......I'm not getting drawn into an argument here as I'm not a spokes person for D-Gas
I will see if I can get Rob from D-Gas come here and explain a few things take it up with him ,I'm only the end user not the maker

[D-GAS]

Originally Posted by Martin from Downunder

Stop......I'm not getting drawn into an argument here as I'm not a spokes person for D-Gas
I will see if I can get Rob from D-Gas come here and explain a few things take it up with him ,I'm only the end user not the maker

Thanks for the invite Martin,

Hi Guys. I was asked by Martin to see if I could clear some things up. Hopefully I can ... I'm not the sharpest tool i the shed but I'll have a go

The 4WD kit of ours does not need to look at TPS however we do monitor engine temp. Our truck kits monitor TPS, temps, boost, RPM.

Our 4WD system does not need to look at TPS or have an installer play around withour maps. They are set at the factory for your car. Installers are not engine tuners ... they are mechanics.

Ask Motec, or Haltec or any other ECU manufacturer on the market and they too will tell you the best way to blow up an engine is to let novices dick around with the ECU map.

Granted SOME may know what they are doing but no 2 hour course is going get the average guy up to speed. This stuff takes YEARS to develop the skills.

Our under bonnet kits are fitted in about 10 hours and all the fitter needs to do is FIT THE KIT plus the jets that sit at the manifold, take the vehicle for a drive and check it all works.

In my opinion, systems that inject before the turbo (seen in Moses' day) need better monitoring because if they over fuel the gas can be ignited from the turbo. This is why they have had version 1 through to 28. They are trying to get the right amount of gas in there without things going of in smoke. One kit out there will only inject UP TO 15% LPG because they are worried about the potential risk. We inject up to 30% because there is no risk of pre engine ignition.

Every car manufacturer out there using petrol injection injects at the manifold? Why? Because it is safer. These are just the facts. I'm just the messenger reporting so please dont shoot me for it.

In our system, if the LPG were to ignite in the manifold (somehow), the manifold could contain the blast. Not so a fragile intercooler. All that LPG being compressed by the turbo and going through an intercooler has the potential for disaster.

With the D-GAS system we have very little gas in the intake to start with.

It is harder to inject after the turbo, for sure but that's where it should be injected .. and it must be at a true rising rate. D-GAS is.

Lastly, adding LPG at idle is the easiest thing in the world to do. We don't do it because we figure people want to save the LPG that is used at idle to be used when the engine REALLY needs it ... under load. Please remember, in most 4WDs we have very little room for ANY LPG tanks. We dont have loads of room for big tanks where we can afford to inject LPG at the time. Save that precious little for the real fuel savings or real power needs. Again ... this is just my opinion!

Hope this has helped

Cheers team

Regards
Robert

PS

If someone can host a pic I will send a screenshot of the software we do use to drive the system.

[Tweak'e]

Originally Posted by D-GAS

Thanks for the invite Martin,

Hi Guys. I was asked by Martin to see if I could clear some things up. Hopefully I can ... I'm not the sharpest tool i the shed but I'll have a go

thank you, i'll try not to be too harsh

The 4WD kit of ours does not need to look at TPS however we do monitor engine temp. Our truck kits monitor TPS, temps, boost, RPM.
..................

so basicly what they are avertising and what has been mentioned in the email posted is not true.

edited on request to make it clearer:
4) System injects LPG proportionally to your driving style. The harder you drive it the more it injects, the easier you drive it the less LPG it uses.
5) No Gassing at idle conditions.
This is not just a function of insufficient air being drawn in by the engine or turbo, our system literally shuts off. This built-in safety feature also works to save LPG when it’s not needed. ie when sitting at a set of lights.

EcoGas - Diesel enhancing LPG - Diesel LPG conversions + injection Australia FAQ
The D-Gas System: ......
• Uses tacho and throttle control (ie no LPG is introduced at idle and allows superior control of LPG).........
D-Gas Equipment
Equipment
........
RPM limiter built-in...........

there is basicly no mention that there is two systems and that certain features only apply to trucks system.
the non-truck version dosn't "injects LPG proportionally to your driving style" or have rev limiter or has an idle cutoff (its low boost cutoff).
its all run off boost pressure only, which explains Is the D-GAS wired to the vehicles Ecu or sensors?
No D-GAS is a fully automatic system & only requires the following wiring to the vehicle, 12 volt live under key, negative, 1 wire to the alternator to sense running of engine.

its only the ecogas site that mentions the extra stuff in the truck section.

i hope that clears up what i mean on the rather poor advertising.

In my opinion, systems that inject before the turbo (seen in Moses' day) need better monitoring because if they over fuel the gas can be ignited from the turbo. This is why they have had version 1 through to 28. They are trying to get the right amount of gas in there without things going of in smoke. One kit out there will only inject UP TO 15% LPG because they are worried about the potential risk. We inject up to 30% because there is no risk of pre engine ignition.

Every car manufacturer out there using petrol injection injects at the manifold? Why? Because it is safer. These are just the facts. I'm just the messenger reporting so please dont shoot me for it.

In our system, if the LPG were to ignite in the manifold (somehow), the manifold could contain the blast. Not so a fragile intercooler. All that LPG being compressed by the turbo and going through an intercooler has the potential for disaster.

With the D-GAS system we have very little gas in the intake to start with.

It is harder to inject after the turbo, for sure but that's where it should be injected .. and it must be at a true rising rate. D-GAS is.

petrol manfactures do not inject into manifold due to it being safer. they are many suck through carb and single injector systems in vechiles around the world. they don't use those system now because they perform poorly.
even overfueling the lpg will not ignite from the turbo. the only problem with suck through systems is if you get flame up through the inlet valves (backfire up the intake) which will set off the fuel in the manifolds etc.
injecting gas after the turbo is more effecient. why decompress the gas then put it in for the turbo to compress ?? thats a waste of turbo power. ditto for intercooling. lpg doesn't need intercooling so why take up gas space inside the intercooler. you need to remember that lpg replaces some of the air, so its better to do all the compressing/intercooling on just air only.

Lastly, adding LPG at idle is the easiest thing in the world to do. We don't do it because we figure people want to save the LPG that is used at idle to be used when the engine REALLY needs it ... under load. Please remember, in most 4WDs we have very little room for ANY LPG tanks. We dont have loads of room for big tanks where we can afford to inject LPG at the time. Save that precious little for the real fuel savings or real power needs. Again ... this is just my opinion!

i can understand not injecting at ilde on mechanical systems because it increases the idle which is a waste. however modern ECU's maintain idle reguardless and will reduce diesel to limit rpm.
now if adding lpg makes it more efficent then its worth while at idle as overall fuel (ie diesel+lpg) compsumption should be reduced. as vechiles spend a lot of time at idle i should think its very well worth while.

2nd thing.....if the basic system doesn't have tps input etc how does it know its at idle ?? i suspect it doesn't, the system dosn't turn it off at idle it turns off when there is no boost. so even with mid rpm, no boost, load or not, you have no lpg assist. pity, it would be so handy in takeoff situtions.

Hope this has helped

Cheers team

Regards
Robert

the other interesting thing i've been looking at is the effect on the variable turbo systems. for eg nissan speficly state that fuel (oil) through the intake will make the turbo operate incorrectly which in turn can have some real nasty side effects.
also if the lpg dosn't go in at rate that the motors ecu can handle it can cause some real hassle as the ecu won't learn properly and will either not perform well or fall back to a safer settings.
common rail is proberly easier as you could tap into injection signal and add lpg as a fixed % of fuel. motor ecu cuts back diesel by that fixed amount and will operate correctly. ecu just thinks its got a real good batch of fuel.

also one thing i would love to know is the effect with water injection. a few companies claimin better performnce and economy with water injection than with lpg. a combo could be interesting.

[D-GAS]

Hi Tweak'e

Thanks for that.

Yes we have two systems but the 4WD system works extremely well and I will put the D-GAS system up against any installer tunable system and know we cover all the bases WITHOUT sensers they need to function well.

REGARDING these points

4) System injects LPG proportionally to your driving style. The harder you drive it the more it injects, the easier you drive it the less LPG it uses.
5) No Gassing at idle conditions.
This is not just a function of insufficient air being drawn in by the engine or turbo, our system literally shuts off. This built-in safety feature also works to save LPG when it’s not needed. ie when sitting at a set of lights.

4) Our system uses some equipment that we have patented with ONLY needs boost pressure to measure what the engine is doing. Remember we are putting the LPG in over boost pressure so we need to do things that others dont do ... even those that use boost only to regulate.

If someone wishes to read what, you'll need to read the patent

5) the system senses zero boost (actually we do fit a throttle switch on some models) that tells the D-GAS controller to cut power to the lockoff so we do in fact switch off the system during idle and coast.

We use a map sensor PLUS and pressure switch. These two parts do separate jobs.

We dont inject at idle for the reasons state above.

With turbos having LPG in them, toll, our largest customer, made abig mention of the fact that they use our system for the safetly aspect as 1 of their boxes they need to tick. There is certainly a safety aspect here. A turbo just needs to loose an exhaust wheel and there's your ignition point. Long shot? Mayby, but it does happen.

Re water injection. Good point. We are playing around with all sorts of things including LNG, hydrogen and other fuels (or potential fuels)

In the other bits in your post I agree totally.

Thanks heaps

RGDS
RR

Originally Posted by Tweak'e

thank you, i'll try not to be too harsh
so basicly what they are avertising and what has been mentioned in the email posted is not true.

edited on request to make it clearer:
4) System injects LPG proportionally to your driving style. The harder you drive it the more it injects, the easier you drive it the less LPG it uses.
5) No Gassing at idle conditions.
This is not just a function of insufficient air being drawn in by the engine or turbo, our system literally shuts off. This built-in safety feature also works to save LPG when it’s not needed. ie when sitting at a set of lights.

EcoGas - Diesel enhancing LPG - Diesel LPG conversions + injection Australia FAQ
The D-Gas System: ......
• Uses tacho and throttle control (ie no LPG is introduced at idle and allows superior control of LPG).........
D-Gas Equipment
Equipment
........
RPM limiter built-in...........

there is basicly no mention that there is two systems and that certain features only apply to trucks system.
the non-truck version dosn't "injects LPG proportionally to your driving style" or have rev limiter or has an idle cutoff (its low boost cutoff).
its all run off boost pressure only, which explains Is the D-GAS wired to the vehicles Ecu or sensors?
No D-GAS is a fully automatic system & only requires the following wiring to the vehicle, 12 volt live under key, negative, 1 wire to the alternator to sense running of engine.

its only the ecogas site that mentions the extra stuff in the truck section.

i hope that clears up what i mean on the rather poor advertising.

petrol manfactures do not inject into manifold due to it being safer. they are many suck through carb and single injector systems in vechiles around the world. they don't use those system now because they perform poorly.
even overfueling the lpg will not ignite from the turbo. the only problem with suck through systems is if you get flame up through the inlet valves (backfire up the intake) which will set off the fuel in the manifolds etc.
injecting gas after the turbo is more effecient. why decompress the gas then put it in for the turbo to compress ?? thats a waste of turbo power. ditto for intercooling. lpg doesn't need intercooling so why take up gas space inside the intercooler. you need to remember that lpg replaces some of the air, so its better to do all the compressing/intercooling on just air only.

i can understand not injecting at ilde on mechanical systems because it increases the idle which is a waste. however modern ECU's maintain idle reguardless and will reduce diesel to limit rpm.
now if adding lpg makes it more efficent then its worth while at idle as overall fuel (ie diesel+lpg) compsumption should be reduced. as vechiles spend a lot of time at idle i should think its very well worth while.

2nd thing.....if the basic system doesn't have tps input etc how does it know its at idle ?? i suspect it doesn't, the system dosn't turn it off at idle it turns off when there is no boost. so even with mid rpm, no boost, load or not, you have no lpg assist. pity, it would be so handy in takeoff situtions.


the other interesting thing i've been looking at is the effect on the variable turbo systems. for eg nissan speficly state that fuel (oil) through the intake will make the turbo operate incorrectly which in turn can have some real nasty side effects.
also if the lpg dosn't go in at rate that the motors ecu can handle it can cause some real hassle as the ecu won't learn properly and will either not perform well or fall back to a safer settings.
common rail is proberly easier as you could tap into injection signal and add lpg as a fixed % of fuel. motor ecu cuts back diesel by that fixed amount and will operate correctly. ecu just thinks its got a real good batch of fuel.

also one thing i would love to know is the effect with water injection. a few companies claimin better performnce and economy with water injection than with lpg. a combo could be interesting.

[Tweak'e]

so why run it off boost pressure only ?
its fairly basic and crude. by tapping into ecu/sensors you should be able to provide better performance and economy. ie matching the lpg to the diesel and not pouring in a lot when there is minimal deisel to burn. boost dosn't neccarly reflex how much fuel is being put in (mine varies from 5psi-12psi just going up/down slight rises/dips on a flat road.
should be able to match lpg soloind pulse to injector pulse, no tuning needed just straight forward match a % of lpg to diesel.

the other question is how does the lpg burn react to heavy EGR systems?

[navara-au]

GO FOR IT PAULY!!!!

That's right I told you to stick to your guns and get a Navara at any costs.

I had mine all booked in when they first granted the 2 grand rebate......but then I found out I couldnt get the rebate as mine is registered as a commercial car......and it was only $3200 then.

Don't know of anyone who has the V6, having it done but I'm sure there's plenty. The VQ motor is a good engine and should run OK on the gas. The last vehical I had running on gas did over 200k with out any problems, actually ran better on gas than petrol and the fuel economy wasnt much difference. Plus there are a better system now.

The problem with the tank is if you dont mount it where the spare wheel is or in the tub you wont have a very big tank so you will need to refill all the bloody time.

You will lose any warranty that can be attributed to the gas but the gas installer should have some sort of warranty????

I would run premium unleaded every third tank full to help lubricate the valves and stuff. I ran flash lube directly into the carb which might of helped.

Anyway its your decision, do some more research and get a few quotes .............and dont listen to me.