LPG economy rates

[mrdenn1s]

The injection systems are a massive improvement over the vapor systems.
Vapor systems are down on power and constrain petrol power also. Injection systems use the same ECU and are difficult to tell what fuel you are running as they mix in the cylinder rather than external to the engine.

 

[typhoeus]

Yes, I have an Emer gas injection system on my 3RZFE and it has been good. It changes from petrol to gas seamlessly, and the power is only just noticeably different. on petrol, it revs out smoother. I have the program and the interface cable so I can adjust the mixture etc with my laptop

 

[muc the truck]

Hi guys/girls!!
Just wondering what sort of kms per Lt you get from your LPG? My 80 series has a roof tent, but I suspect something is up as my 85lt tank yielded just over 300km, and I don't think this is right. Am I wrong? Cheers

I don't have my v8 disco anymore thanks to a druged driver . It was lifted and 7foot tall at the roof . cost the same to drive a v6 vs commodore sedan on petrol . 300kms on 85 ltrs is not bad but it can be improved .

Iridium denso power spark plugs are the only ones to use. It pays to buy them from ebay usa. it will return you savings owning them.
Have you dizzy regraphed to suit lpg or use an ignition advance device like this http://autoparts.rasoenterprises.com/timing-advance-processor-patinos

 

[muc the truck]

The injection systems are a massive improvement over the vapor systems.
Vapor systems are down on power and constrain petrol power also. Injection systems use the same ECU and are difficult to tell what fuel you are running as they mix in the cylinder rather than external to the engine.

injection of any fuel is better than sucking any fuel because its delivered more accurately . but how do believe lpg constrain petrol power output aswell. Both injected and draw though systems deliver lpg to the intake manifold its just injected is closer to the intake valves. Its still possible to get extremely powerful systems out of a draw through lpg gas system . I have a old 2.2 ton sandman that by gps has sat on 233kms per hour on a 20 year old sprint gas set up. Stuart Highway Unlimited speed limit .

Compression is the biggest killer on lpg performance . the lower you go the worse it is . above 10:1 lpg loves delivered anyway you want.

 

[muc the truck]

22 lp100, 4.5 80 series, 33"muds,3"lift roof rack, bar, winch, draws yada yada yada.
Old style mixer system tune advanced 2 degrees on dizzy, without this it pings its head off.

Heads ****ed after 10yrs on lpg but still goes ok, 300k on engine.
Gunna wack a new head on it and see Iuf i can get 600k out of the ol girl.

any head built for unleaded is suitable for LPG and despite what people have told you , Lpg does less damage and casues less wear to an engine than petrol . There is no cylinder wash that dilutes the oil like petrol causes , oil stays cleaner so lubes better . So if you never ran petrol ever again your engine will last longer . its just that running lpg all the time tends to make fuel injectors sieze as there not getting lubed by petrol additives . It cost me 8 injectors for running on lpg for 3 years .

 

[muc the truck]

my Disco has a high torque cam and cam timing is advanced by 3 degrees and dizzy is also advanced by 9 degrees so its awesome on LPG but I do need to run 95+octane fuel so it doesn't ping its head off. Around town and cruising it averages 22l/100 on fuel or petrol towing and average 4wding its up to 25l/100 worst I have seen on soft sand towing over a ton of camper it is up to 35/100
most of the time with fuel cost and maintenance costs all taken into account its about same as old diesel to run and half the cost of a modern diesel.
I have kept all fuel and maintenance cost because its also my work car so its a tax deduction and over 100,000km it averages $17.00 / 100 km
A modern diesel over 100,000 will cost on average 7k just in injectors, pumps and turbo replacement costs and that's without servicing or fuel so after all the other costs LPG is way cheaper.
That is comparing a 18 year old car to a new car so totally irrelevant
As far as "you cant get LPG no range" bla bla bla I have a range of 1000km and have never had an issue of getting LPG in 99% of places so that's also a irrelevant comment

get one of these http://autoparts.rasoenterprises.com/timing-advance-processor-patinos

 

[80lover96gxl]

any head built for unleaded is suitable for LPG and despite what people have told you , Lpg does less damage and casues less wear to an engine than petrol . There is no cylinder wash that dilutes the oil like petrol causes , oil stays cleaner so lubes better . So if you never ran petrol ever again your engine will last longer . its just that running lpg all the time tends to make fuel injectors sieze as there not getting lubed by petrol additives . It cost me 8 injectors for running on lpg for 3 years .

Thats interesting to know muc, cheers for the info.mate.

 

[GUnka]

The injection systems are a massive improvement over the vapor systems.
Vapor systems are down on power and constrain petrol power also. Injection systems use the same ECU and are difficult to tell what fuel you are running as they mix in the cylinder rather than external to the engine.

You sure about that? Am pretty sure most LPG injection systems are in the manifold just like most EFI petrol engines and are not direct injection as it's better known into the combustion chamber/cylinder.

 

[mrdenn1s]

You sure about that? Am pretty sure most LPG injection systems are in the manifold just like most EFI petrol engines and are not direct injection as it's better known into the combustion chamber/cylinder.

http://www.ls1.com.au/forum/archive/index.php/t-96418.html

 

[GUnka]

http://www.ls1.com.au/forum/archive/index.php/t-96418.html

That is not direct injection, it is still injected external to the cylinder via the manifold as per the below quote from the link you posted.

Quote "The injectors deliver liquid LPG directly into the manifold via a small tube. This is installed much the same as vapour injection. A hole is drilled in the manifold as close to the petrol injector as possible and a nozzle is taped in. The difference is that the liquid is passed through a small inner hose that is inserted into the nozzle. An outer hose is then placed over the smaller hose and onto the outside of the nozzle."

 

[typhoeus]

My emer system has its own ecu, and the injector nozzles are drilled into the manifold very close to the head. the advantage is more precise metering of the gas. The old style " bolt to the carby" ones were very vague in the mixture control, especially as temps vary.

 

[muc the truck]

If you only new the horror of injected lpg kits . I had the choice to put my v8disco on injected gas but no way was I going to let some mug drill 8 holes in my intake while the manifold was fitted to the engine then run a tap into those holes to make threads , (that's how its done) dodgy pricks put grease on the drill and hope the aluminium swarf doesn't fall into the combustion chambers . ( it does) How do they get rid of any that do . well on first start up a fast stab on the loud pedal sorts it out apparently . Don't believe me ring up and get quotes for lpg injection and then once they give you a figure ask them if that's including machine work to the manifold off the engine to ensure metal doesn't go into the engine? you will be dumfounded. I have a mate that lost his xr6 nonturbo to lpg injection cowboys . weeks after the installation the oil light came on and this was after he complained of the car having lost power on both fuel and lpg . the car was 12 months old. the oil light never came on between oil changes before . Ford said straightaway you have rings bound up by aluminium shards from the injected lpg installation . And sure as hell they were right . 3 pistons has rings frozen stiff scoring the bores , all six pistons has aluminium pounded into the ring gaps . Cost the blokes mum a new engine at a point of time when he was still an apprentice and borrowed money for the lpg to cut his travel cost to work , his finances were maxed out on the car and lpg . Lpg installer wiped his hands of it and got really nasty and accused the guy of blowing his own engine up by mishandling it .

This is the reason I had suck through system fitted.

 

[typhoeus]

Yes, I see your point about dodgy installers, but the actual principle is sound. Now that fuel is cheap, its hardly worth the cost to fit lpg, but petrol will go up eventually, and then maybe it will be economically viable for people to fit them again. I had different issues with my install so if I had one installed again, I would do as much of it as I could myself, and if that wasn't permitted for licencing reasons,, I would supervise the job till I was happy with it.

 

[4runnerSteve]

If you only new the horror of injected lpg kits . I had the choice to put my v8disco on injected gas but no way was I going to let some mug drill 8 holes in my intake while the manifold was fitted to the engine then run a tap into those holes to make threads , (that's how its done) dodgy pricks put grease on the drill and hope the aluminium swarf doesn't fall into the combustion chambers . ( it does) How do they get rid of any that do . well on first start up a fast stab on the loud pedal sorts it out apparently . Don't believe me ring up and get quotes for lpg injection and then once they give you a figure ask them if that's including machine work to the manifold off the engine to ensure metal doesn't go into the engine? you will be dumfounded. I have a mate that lost his xr6 nonturbo to lpg injection cowboys . weeks after the installation the oil light came on and this was after he complained of the car having lost power on both fuel and lpg . the car was 12 months old. the oil light never came on between oil changes before . Ford said straightaway you have rings bound up by aluminium shards from the injected lpg installation . And sure as hell they were right . 3 pistons has rings frozen stiff scoring the bores , all six pistons has aluminium pounded into the ring gaps . Cost the blokes mum a new engine at a point of time when he was still an apprentice and borrowed money for the lpg to cut his travel cost to work , his finances were maxed out on the car and lpg . Lpg installer wiped his hands of it and got really nasty and accused the guy of blowing his own engine up by mishandling it .

This is the reason I had suck through system fitted.

Based on what you are saying the biggest problem with an injected system is that the insulation is often done poorly. Am i right in thinking then that if you could find and installer that was going to remove the manifolds and do the whole job properly then injected is the better option? I don't know much about it I'm just interested.

 

[typhoeus]

I am very happy with the performance of my system, just not happy with the way it was installed. Like Muc said, they chuck 'em in quick to get the $, and don't really do a professional finish.. . Altho I'm sure there are good installers out there, ones who take pride in their workmanship, but I haven't found one yet, I've been over mine refitting, rerouting pipes & wiring etc to make it neat, moving them away from heat, or sharp edges, etc etc.

 

[discomatt]

There are now 2 types of LPG injection, liquid and vapour, I have no idea what is better or any performance details so a another bit of useless info
One thing I do know for certain is the type of system needed to get the best depends on the car and model, the old style mixer and converter works very well on a series 1 Disco but will not work on a series 2 Disco, they must have a computer controlled injected system or you have nothing but
tuning issues with constant back firing unless the plugs and coils or brand new. Yet the injected system is a total waste of time and money on a D1.
It all depends on the ECU system in the car and how the LPG computer talks to the car, if there is no oxy sensor, crank angle and knock sensor stick with the basic draw system

 

[mrdenn1s]

Mine is vapour sequential injection. Just installed last week. Replaced the existing mixer system that was gutless.

The installer put the gas ECU behind the firewall to keep it away from heat in the engine bay. Ran it on the dyno. Wants it back in 4 weeks time to ensure it is doing as it needs to. It's a Prins system from Netherlands. Can't fault it so far. Can only marginally tell the difference between gas and petrol at higher revs. Starts on petrol, automatically shifts to gas and back again when the tank runs dry. Seamless.

Ran my gas tanks dry and refilled today.

72 useable litres from the 80 litres available in the tanks.

Got 300 kms from first tank driving from the Dandenong ranges to Queenscliff and back. Massive headwinds, 5 passengers, gear and approx 90 litres of petrol in the tanks. A little bit of weight.

But let's do the maths.

I got 24 litres / 100kms on gas.
On petrol, my 105 series 6 cylinder Landcruiser does about 16l/100 at best
Conservatively 55c / litre v $1.10 for petrol at today's rates in Vic.

Maths stack up if you are holding the car for any amount of time.
Past your breakeven date, every year you might be banking $1k plus. Think of the new accessory you can buy with that

 

[muc the truck]

Based on what you are saying the biggest problem with an injected system is that the insulation is often done poorly. Am i right in thinking then that if you could find and installer that was going to remove the manifolds and do the whole job properly then injected is the better option? I don't know much about it I'm just interested.

exactly , but what I found after ringing half dozen installers that could accommodate a week end pick up as I lived 300kms away all I found were installers that never removed the intake at all , since then I have still not come across a workshop that removes the intake . Yes the injection system is better but you had better stand behind them when they drill holes in your intake and watch .

 

[vladau]

5vz-fe
BRC AT90E ("carby type")
70L tank (appx 55L usable?! wtf)
20-24L/100km
savings for 2 years, 25K km, appx $1500 (actually, I replaced a rusted tank for $400 so it's $1100)

 

[tankbloke]

5vz-fe
BRC AT90E ("carby type")
70L tank (appx 55L usable?! wtf)
20-24L/100km
savings for 2 years, 25K km, appx $1500 (actually, I replaced a rusted tank for $400 so it's $1100)

55l for that tank means it is so close to the 80% max allowed by the standards.
Plenty of cowboys out there will bend the float arm up to allow it to overfill for you if you don't give a ..