5 litre to gas?

javelin · 20-04-2008, 10:13 AM

I have booked my 5 litre, au xl ute in to get it fitted with gas, and was wondering if there is anything I should be carefull of ?
It's not going in for 6 weeks so that gives me some time for research.

JC · 20-04-2008, 11:01 AM

Is it a mixer ring setup, or are you going SVI/VSI? I'll assume it's mixer ring - if it's SVI, then you can pretty much ignore the following.

Make sure you get new, correctly gapped plugs (Bosch copper core is all you need, not the more expensive iridums or platinums), and a new set of LPG compatible leads such as TopGun Max300s, or Bosch Sports Induction (expect to pay around the $200 mark for the new leads - plugs should be around $30 for the set).

I am suggesting this from experience. When I got my AU XR8 converted to mixer ring setup (Landi Renzo complex converter), I had heaps of backfiring issues initially. It turns out that the near new Motorcraft leads were "leaking" spark. LPG is very spark sensitive, so it is vital that your leads and plugs start off new, and I would recommend replacing them every year (or at the latest, every 30,000km).

The good news is that it doesn't really matter which setup you go for, with a well tuned system, you will not lose too much power - in fact I went from 144rwkw on petrol, to 138 rwkw on gas (same dyno same day, both after conversion so it included the restriction of the mixer ring in the TB which can affect petrol performance). My previous highest reading on a different dyno was 147rwkw. I was also getting around 18l/100km on gas - which is not much more than the 16 odd I got on petrol prior to conversion.

So....in summary, welcome to the world of cheap(er) fuel. With petrol currently on 150cpl, you are going to enjoy filling up at anywhere between 60 and 75 cpl.

javelin · 20-04-2008, 03:07 PM

It's a mixer ring setup, so they say, thanks for the tips on the spark.
I will go and see them next week, and find out where they intend to put the filler fitting, as I don't realy want them knocking holes in my panels.
My last ute was a BA dedicated, so I know what you mean about cheaper fill ups.
I usually only fill up once every two, or three weeks, so it will only save me about $20 per week, it will still pay for its self in 12 months.
My exhaust is due to be replaced anyway, so that extra mod doesen't worry me.
With the Government rebate, it will cost me about $900 out of my pocket, so I can't complain.

JC · 20-04-2008, 03:26 PM

Quote:

Originally Posted by javelin

It's a mixer ring setup, so they say, thanks for the tips on the spark.
I will go and see them next week, and find out where they intend to put the filler fitting, as I don't realy want them knocking holes in my panels.
My last ute was a BA dedicated, so I know what you mean about cheaper fill ups.
I usually only fill up once every two, or three weeks, so it will only save me about $20 per week, it will still pay for its self in 12 months.
My exhaust is due to be replaced anyway, so that extra mod doesen't worry me.
With the Government rebate, it will cost me about $900 out of my pocket, so I can't complain.

They fit the LPG filler in the existing fuel flap next to the petrol filler. It can get a bit tight in there, but on my AU both were easily accessible. On my NF, they're both hard to get to, so a lot depends on the installer. I've got the same installer that did my AU doing our Explorer, so I'm hoping he does just as good a job on that so that each of the fuel fillers are easy to get to.

With the exhaust, on a 5.0, get them to use 3" single pipe to get around the gas tank - it will have some funny angles in it, so if they only use 2.25 or 2.5", it will be very restrictive, whereas 3" will open it back up a bit.

javelin · 20-04-2008, 05:31 PM

Nar, I want to use twin 2" if I can, through a single 2 in 2 out muffler as used on the old Holden 1 toners.
It might be a bit tight, but should be ok, I used to work as an exhaust fitter years ago, and I reckon I could do it, without to much trouble.
I don't like the sound of a single system on a V8, sound like a 6, once past about 1500 revs.
Twin 2" is about the same area as single 3", and easier to work with.
My ute currently has a single 2.5" pipe, and drones badly at 100 -110 kmh, drives me nuts.
Wouldn't mind a set of "Hay burners" to make it sound like a real V8.

but I don't think "Mister Plod" would like it much.

sly · 21-04-2008, 05:30 PM

Quote:

Originally Posted by JC

They fit the LPG filler in the existing fuel flap next to the petrol filler. It can get a bit tight in there, but on my AU both were easily accessible. On my NF, they're both hard to get to, so a lot depends on the installer. I've got the same installer that did my AU doing our Explorer, so I'm hoping he does just as good a job on that so that each of the fuel fillers are easy to get to.

Not long had my wife's AU3 wagon done. The filler is harder to get to than my AU1's 4 year old setup. Apparently standards have changed and the new fillers required to meet current standards are more cumbersome than the older ones.

stavros68 · 20-04-2008, 05:36 PM

My fairlane's V8 is on gas had problems at the start but it all came down to the leads,plugs that I am using are irridums havent had any back firing issues yet.

JC · 20-04-2008, 07:09 PM

Quote:

Originally Posted by stavros68

My fairlane's V8 is on gas had problems at the start but it all came down to the leads,plugs that I am using are irridums havent had any back firing issues yet.

Yep, leads are a common issue for LPG powered windsors, because of the sprk plug angle, the leads sit close to the exhaust manifold, which leads (no pun intended) to premature failure - on petrol, it's not that important, as you'll just get reduced spark and reduced power, but on gas, this leads to manifold backfires.

Also, you won't have any issues using iridiums, but you are flushing money down the drain. You will not get 50,000 let alone 100,000 out of a set of iridiums on LPG. At best, you may get 40,000 fault free km. At roughly $18 per plug, it makes more sense to use $4 copper core plugs and replace them at 20 or 30,000km intervals.

OzJavelin · 21-04-2008, 12:40 PM

Quote:

Originally Posted by javelin

I have booked my 5 litre, au xl ute in to get it fitted with gas, and was wondering if there is anything I should be carefull of ?
It's not going in for 6 weeks so that gives me some time for research.

Has an AU XL ute 5.0L and is named "Javelin" .. have you stolen my identity?

JC · 21-04-2008, 01:20 PM

Quote:

Originally Posted by OzJavelin

Has an AU XL ute 5.0L and is named "Javelin" .. have you stolen my identity?

Maybe he's looking to spear your car!

javelin57 · 21-04-2008, 05:11 PM

Quote:

Originally Posted by OzJavelin

Has an AU XL ute 5.0L and is named "Javelin" .. have you stolen my identity?

You can blame "Rodney Rude" for the name.
I was up on stage with him one knight singing "ditties" and due to my 185cm & 75kg frame, he was calling me "The man who looks like a javelin" and it kinda stuck.
And for some reason my user name "nomad" (derived from my mobile mechanical bussiness of years gone by,"Nomad mechanical" )from the other forum didn't work here.
So no attempt at identity theft, just a happy coincidence

5.0 ED · 22-04-2008, 01:07 AM

Thats interesting about the fillers cause we make them at work and they are smaller than older ones i have in the shed, for some reason we make high flow fillers and AFL's for a gas tank company, there suppost to flow 50% more, and when they tested them they found that it still took the same amount of time to fill the tank, cause ya know a high flow filling setup is really going to increase the speed of the bowser at the servo.

au2sw · 22-04-2008, 06:04 AM

^^^^^perhaps your getting ready for when servos introduce high flow LPG pumps. i have noticed that now with fitting 10mm fill line it does seem to flow a little faster then the old 8mm...but again, it all comes back to the pumps.
Javlin, i know that when we fit our systems to the Falcon V8s, we remove the snorkle and cut a large hole in the underside of the airbox to allow placement of our converter (before any one says anything, we have a remote lock off fitted closer to the firewall, so there is no issue there.....we are completely up to date with rules and regs being the largest LPG conversion center outside of Melbourne). We also use and recommend ICE pro leads and NGK spark plugs. we find we have too many problems with Bosch plugs (dont last anywhere near long enough for our liking, and Ice leads last longer then any other leads on the market. however, if ICE is out of your price range, we recommond Eagle as an alternative. Of course, your fitter should check these things and replace as nessesary during fitment of you system. anothewr thing you need to be on top of is the air filter. make sure its clean if not new as a dirty air filter will also cause backfires, poor air flow etc. good luck

OzJavelin · 22-04-2008, 07:31 AM

Quote:

Originally Posted by au2sw

Javlin, i know that when we fit our systems to the Falcon V8s, we remove the snorkle and cut a large hole in the underside of the airbox to allow placement of our converter (before any one says anything, we have a remote lock off fitted closer to the firewall, so there is no issue there.....

So the converter is on the passenger side? On my Parnell install, the converter is behind the radiator on the drivers side and the vapour line runs all the way up to infront of the throttle body. Many have told me this is the reason mine won't start first go on gas (always at least two attempts). Even with the petrol start (2sec) the LPG takes too long to travel all that way to the mixer and it cuts out ..

javelin57 · 22-04-2008, 10:10 AM

Dunno were they put the converter, Marjac are doing the installation, they said they replace the plugs with colder ones, and close the gap a bit.
It's all included in the $2900 quote, only thing on top of that is the exhaust.

JC · 22-04-2008, 09:30 PM

Quote:

Originally Posted by OzJavelin

So the converter is on the passenger side? On my Parnell install, the converter is behind the radiator on the drivers side and the vapour line runs all the way up to infront of the throttle body. Many have told me this is the reason mine won't start first go on gas (always at least two attempts). Even with the petrol start (2sec) the LPG takes too long to travel all that way to the mixer and it cuts out ..

The converter on my AU XR8 was low down on the drivers side, behind the radiator, and I never had those issues.

I'd be going to a different LPG mechanic, and ask them to change the LPG changeover to either 40 degrees water temp, or when you rev the car, as it passes 1500rpm as the revs rise; mine was initially set to 1500rpm, but on the way down, and it would often stall. Once I got it changed to 1500rpm on the way up, it never stalled on startup. The reason you choose 1500 is when the car starts, it will rev up to about 1300, so 1500 is chosen so that YOU are in control of the changeover.

My new SVI system cuts over once water temp reaches 40 degrees - it is pretty seamless changeover, and for Canberra winters, will be the way to go to ensure that the converter is working at temp prior to running on LPG.