LPG - Pros V Cons

[mulligan-can]

So, I'm interested in hearing about the pro's and con's of running LPG/Gas in a VN. I don't know much about it but I know some people swear by it and some people swear at it.

Is is possible to run both gas and petrol and have like a switch to change between the two? How much power do you generally lose? Is it actually worth putting gas into a VN? Does the engine wear faster? Is a well maintained engine with say 250 000 on it a decent candidate to having gas installed? What about with 150 000 on it?

Interested in knowing anything and everything

[kniever]

when they put the lpg in ure car they always put a switch in to change from lpg to petty cos its always good to run ure car on petty every now and then

also i personally dont like gas cos in the cars that i have had with gas i have found that the engine hasnt been at its full potential and its worn out fast but they were pre 1990's car but a few mates that have gas in their 2000+ cars seem to run pretty good but thats my opion and experience but im sure someone else will say differant

[V8 Berlina]

GAS injection is good, better l/100km, with the same power out put.
Tuned by a comp. Gas cuts in when the engine is at a set temp say around 35c. Carnt even feel the change over, just hear the relay click on. Im my opinion gas injection is very good.

[V8 Berlina]

Also our fleet all run gas now with a huge saving each month. The money we save on fuel for 2 cars covers the lease cost of another 1. Well worth it.

[mulligan-can]

I'm more interested in how an older car like a VN with 250 on the clock will handle it. Any dangers?

[TUF UTE]

used to be a gas fitter, the cost of having gas fitted... it will take u 2 years before u actually start breaking even from the 2+ grand u spent to get it fitted

gas is harder on your motor, takes a different tune, stronger spark, more weight in the boot, ur leads have to be thicker, u need different gaps in your spark plugs.... u will always have one source of fuel running abit lousy to have the other source of fuel run good due to tuning. also gas has to be tuned fairly regularly especially on commos as once it starts getting out of tune it will start running like **** and back firing and blowing up airboxes which are about 30 each...

con's of gas ITS CHEAAAAP !! lol

[Pimpt6]

I recently fitted a new gas system to my vr commo with about 210 000 kays on the clock. Yes I have lost a little power but when you get nearly 500 kays to $40 of gas you think hey thats not bad considering before i use to only get 200-250 kays to $50 of juice if that! When I want the power I just flick the switch back to petrol. I havnt had a problem. . No back firing no nothing. It runs Sweet as

[skyper]

my vn i put on gas not long after the deal from the goverment came out ,it had 250,000 on it ,and likes some of the others have said it has more than cut my fuel bill in half,now, my car runs like a dream,there is NO difference in power which was my biggest worry but no i am very very pleased i hardly ever run it on petrol ,it cost $2700.00 to fit and then $2000 back from the goverment,the brand is empco or something like that,and the man who fitted it had 30 years experience and he liked this brand the best, now when u turn it back to petrol there is a difference but i can't explain what it is,i think it is smoother on gas ,i have not changed a thing,yes i put new leads on it and plugs ,but after 250,000 u do that anyway,i thought i was making a mistake ,but no very happy

[DavoVP]

yeah gas is good if its set up and tuned properly, But it does require maintenece etc and all that.

LoL if you have a weak ignition system or its outa tune, you will detonate air boxes, trust me :P

[TUF UTE]

would have been impco and from experience thats one of the most annoying brands for faults with the gas convertor

[skyper]

yes that sounds like it and i remember him talking about the converter and he mention that people mount them wrong ,one way they surge and the other way they run great,i have not had to touch it since fitted and hasn't missed a beat

[centy]

just scored a 92 vp and repleaced the engine with another that had about 160k on it.
Being and older gas system, first of the new type it is down on power a little but ****loads cheaper to run. In the highway it also seems to be smoother and require less speed adjustment with the pedal.
Also the injectors being off make the engine real quiet.
ONLY concern i has is MAYBE i shoud fit a flash lube kit to keep the upper cylinder lube going.
o yeah you loose a big chunk of boot space.
All in all worth it if you can get it for a good price.

[vnv8driver]

On a high kilometre motor which has been run on petrol its whole life the amount of wear & tear is not that bad until you HAVE run it for years straight on lpg without much petrol use, as mentioned the cost of setting it up wont be making you ANY profit for a little while as the installation, lpg kit & tuning costs a bit even with the redemption (to get it running properly)


What hasnt been mentioned, long use of straight lpg will damage your motor if you give it a hard time as lpg doesnt offer any lubrication up top. friction baby friction!

[levymetal]

how does a 304 go on gas? i've heard they like gas, but i don't know anyone who has one. after going from my old car on gas to my new one on petrol, i feel i am simply wasting my money on petrol when it does the same job. lose 5kw maximum, for $50 in your pocket every week. the choice is simple...

oh and to anyone who thinks gas lessens the life of your engine: get in an AU falcon taxi, look at the odometer, and tell me what you find

[TUF UTE]

my 304 ute was on gas

i removed it and sold it


gas is for bbq's


kthxbai

[vnv8driver]

If everything's tuned right & compensated for you pickup more power, you only loose power if you slap a lpg kit on and drive it as is... most people only tune the converter and dont worry about the motors electrical system & standard tuning

[levymetal]

my 304 ute was on gas

i removed it and sold it


gas is for bbq's


kthxbai

Ah, pride! Imagine how many people think you are so much more awesome, now that you don't drive a car on gas and say it's only for BBQs.
Having that pride must feel so good, who cares about saving a couple of grand a year to do up your car?

I asked a serious question, if there's any more losers with pride who want to comment - go keep your pride and **** off.

Thanks for your reply vnv8

[centy]

if you look at the specs for the gas kit some of them turn the injectors on a little when under high load so as to provide a small amount of upper cyclinder lube and stop the valves recessing into the head.
That type would be best and add a flashlube upper cyclinder lube kit aswell.

[alien]

I stear away from gas. All the mechanics i know too dont have any gas cars (except for one who only has gas because his dad got gas in that car ages ago). That guy hates it too, it's all been tuned but doesn't have anywhere as much power as what it can have.

LOL, i also like having the option of choosing from a few different spark plugs :P Instead of the one LPG type. And yea, my supercharged VY isn't gong on gas for anything :P I get enough fuel economy, i can go from Sydney to Melbourne on one tank with fuel leftover And yes, that was with the 125km of roadworks stretch on the bloddy hume in NSW! >_<

[EACRUISER]

Plus one to blowing up airboxes with LPG.
My car has destroyed 3 in the last 2 months.
Put it down to too much vacumn developing in the intake manifold and airbox. sucking LPG out of the mixer through the pin hole in the throttlebody.

As with the pod on there and no restriction, It backfires rarely.
and it spins the wheels if i plant it in 2nd.

I had only just put in a VR ex cop motor into my VN calais before i left for NZ for work. Will start tuning the LPG when i get back to Adelaide on the 21st. Hopefully the battery hasn't gone flat on it.

Guessing its just the Sensitivity control on the convertor, as the high flow gas adjustment seams to be pretty right.

So, I am on the Positive Side OF LPG. If set up right its a better fuel then petrol, due to the higher octane rating. you can bump up the compression abit more and give the timing a remap with a new chip and have a kick ass setup. As long as the mixer isn't too small to pose a restriction to flow into the throttle body. The one that was on mine was, but i have machined out the mixer to solve that problem.

Talk to a few places to get ideas on how they would setup LPG for your particular model. Tell them what your after, performance or economy and listen to their ideas for your system.
But set a base set of questions to ask each place so you can work out who will install a system that suits your needs.
Best way to do it, as there are some dodgy places and some good places.

But definitely LPG is worth it.

[padrickz88]

seriously convert to gas

the power loss isn't that much anyway and you wont notice it unless you thrash your car everywhere. in that case, stay with petrol if the couple kw is worth it to ya

and i think your engine should be fine, just run it on petrol every week.... even if its nto for long, just give it something


btw, mine has been on gas and given hard a fairly often and is fine

[vnv8driver]

[QUOTE=centy;931570]if you look at the specs for the gas kit some of them turn the injectors on a little when under high load[QUOTE]

nice idea, ideally that is the best option as its truely a dual-fuel car then....

[levymetal]

As with the pod on there and no restriction, It backfires rarely.
and it spins the wheels if i plant it in 2nd.

so you recommend using a pod filter instead of an air box? i have a SV airbox which i don't want to ruin, was going to buy another one, but instead may just get a pod

[EACRUISER]

You must seal the pod away from the hot engine bay air though.
On my car the left front corner area is boxed in with the pod inside the box. I also have a 3" flex pipe plumbed in through a 3" hole cut out of the area under where the airbox once was, the other end is a direct feed from the front bar facing into the incoming air.

If i wasnt 3,056Km's from home i would post a picture to show you.
It seamed to resolve alot of the tuning issues relating to vacumn with the LPG in the intake, and removed quite alot of restriction caused by the factory airbox. also the feed from the front dropped the intake charge at the throttle body around 5degrees compared to the stock airbox. and on a cold night quite alot more the 5 degrees.

I am not using a cheap pod either. Its a Trust foam Airfilter which cost around $160 from cartoys.

This is just my observations with a temperature probe, vacumn gauge and many test drives tuning the LPG on my specific Car. Also specific to my car i have now started to play with tuning. Its running a slightly modified HSV Tune, but its still nowhere near perfect yet.

[STEALTHY™]

Pros = none


Debate settled.