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Hi all, i just brought myself a brumby.
i wanna convert it to lpg as i do alot of highway driving.
is it legal (or even a good idea) to have one of thous spare wheel
donut tanks in the engine bay where the spare tyre norally goes??
( i really dont want a big tank in the tray as it kills to much of the room)
any ideas etc?????

too true as to the cargo space lost , but it is always a compromise.
The ASNZ1425:2003
has a note that would make the underbonnet fitment allowable so long as it continues to adhere to the standard.

Notes: the attachment of a container to the roof of a vehicle, and particularly to the gutters, is generally considered to be of inadequate strength, and unsatisfactory for a number of reasons and is specifically banned in some states legislation.

So, if some do allow roof install, cannot see why a small donut is not do able under the bonnet - though maybe, under a a frontal impact the possiblity of the container being ruptured by the engine etc - may not be allowed. You'd need to make some local enquiries.
Where you gonna put your spare ?

As funny as it seams, ill put the spare in the tray, on the side i think. if i take it at all. if im in town it wont matter, if im heading bush ill just throw it in.
My biggest concern with the donut under the bonnet would be the heat of the engine and how it would affect the lpg in the tank. any idea what the max safe temperature the tanks can operate at would be??

Due to the specifications of LPG and tanks, the heat would not be a problem. A gas tank under the back of a loaded familly Falcon wagon, driving on a hot bitumen highway, gets very hot from heatsoak.

You would only be able to fit a very small tank in there and it would not be viable, even if you could get one small enough to fit (i dont think they make them that small, for that reason).

well aside from engine bay and tank in the tray, any other places i could mount a tank?

If your converting to a full gas system, you could swap the exisiting tank under tray ...

Although please note that I haven't heard any good things about gas conversions, as Subaru engine's generally don't seem to like it + the ones I have seen, have since been removed ...

so they dont like lpg? i was thinking small engine/cheap fuel win win lol

EJ 22's don't mind LPG, done properly.
Motor upgrade time?
LPG and turbo, done properly, is close to the ultimate, but has to be done by someone who knows, not your average lpg installer.

If you go into the physics of LPG, turbo and heat, you will find some amazing figures.
Better motor upgrade?, but a lot of $ to get it working properly.

A good Brumby motor, tuned properly will give good figures on petrol, provided your not running 14" 27x8.5 or similar.
Would almost make LPG not worth it.

Bantum wrote:Although please note that I haven't heard any good things about gas conversions, as Subaru engine's generally don't seem to like it + the ones I have seen, have since been removed ...

Well, I think this is a myth. The trick to LPG setups particularly on old carbie setups is to tune the engine correctly to use LPG. The problem here is that you need to make a compromise - either tune for gas performance and economy or tune it for petrol - can't have both without a tuned ECU.

As for the gas tank in the engine bay, I don't think the tank would be the issue, the filler pipes etc would be the problem in the event of an accident. But speak to a gas installer and possibly an engineer and see what they reckon. I think Bantum got it right with the removal of the fuel tank and replace it with gas tanks.

Dad's rangie had it's fuel tank removed and replaced with two or three gas bottles that gave us about 400km of range with a fully loaded vehicle. A 20L petrol tank was fitted on the side rail for those times we ran out of gas.

Cheers

Bennie

engine swap is out. i want a 4x4, not a project car. i'll def keep the ea81 non turbo.
a weber conversion will prob be as far as i go down the performance side.
i wanna keep it petrol or duel fuel.

My point exactly - It might be cheap to buy gas, but add all the maintenace + cost of installing, it's not worth it in my opinon ... Unless you're a uber super duper mechanic who know's all about gas systems ...

P.S. - Sorry if I offened anyone, but just pointing out the pitfall ...

i can buy the whole gas kit + tank for under $500. install is pretty easy, the tuning would be the hard part. but is it worth it :/

daggels wrote:i can buy the whole gas kit + tank for under $500. install is pretty easy, the tuning would be the hard part. but is it worth it :/

Tuning shouldn't be hard. Gas mix sorted then timing to get the most out of it.

I'm one of those naughty ones that wound out the "mixer bolt" on my old torana over summer for some go faster fun when I wasn't really on a budget, I'd wind it back in when I went back to uni. Working that out was basically wind it in, go for a drive, if there was no power wind it out a little bit until it could drive normally again - counting how many turns in you did and making sure you didn't turn out that far or further!

If you do put a doughnut under the bonnet, how much usable gas will you have in a tank that size?

Cheers

Bennie

I have tried several different brand LPG systems, the correct Impco is the simplest and most relaible.
Other brand systems are more complicated, poor quality mixers, or harder to set up and if not done correctly (dynoed, scoped and tuned) will give problems. These are the ones people usually give up on/remove.
If you buy a second hand LPG system, for reliability/efficiency you sould re-kit it and set it up to manufacturers specs.

Yes, fitting is easy, but unless the rest of the stuff is good, its pointless.

Good LPG setups are worthwhile, I have 3 L's on impco LPG, be carefull what you choose.

is there anyway to get a non-ecu mixer DF set up to run well? or is it pretty much one or the other?? iv seen some tank setups on holden 1-tonners where they have long thin tanks hidden under the tray. would there be room for such a setup on the brumby??

Bantum wrote:If your converting to a full gas system, you could swap the exisiting tank under tray ...

Although please note that I haven't heard any good things about gas conversions, as Subaru engine's generally don't seem to like it + the ones I have seen, have since been removed ...

Phhhttt.... says Jonno with EA81 on LP since 2002, 2008 on the EA82T... I think the dual fuel applications and their installation may have let some people down
and I know the heat soak problem of the Falcon wagons raer twin tanks and heat soak - have had to crawl underneath with a bag of ice and chuck it up and about tank then hose it to cool it enough to refill

I've not seen a small enough donut that may be same as 185 70 14 tyre as the max, but does not say they are not available.

Dummest request that came in to one component supplier was a complied kit for a Smart - the reply was got just one left and it goes where the passenger seat was

daggels wrote:is there anyway to get a non-ecu mixer DF set up to run well? or is it pretty much one or the other?? iv seen some tank setups on holden 1-tonners where they have long thin tanks hidden under the tray. would there be room for such a setup on the brumby??

No room between rear diff and cabin underneath and not all that much room from rear diff to towbar even if you removed the fuel tank. Clearance must be something like the angle from the ground at the back of the rear wheel and straight line back and up to the rear most of the body including towbar - bottle must fit within that line..

I woudnt be sure about the donut tank in the engine bay may not fit but worth considering.
If you're planning on having straight gas, like someone said above, remove fuel tank and replace it to small gas tanks (You might be able to install 4 or 6) I'm considering about adding another gas tank for my work's Falcon (its straight gas) to give me longer range between re-fuelling.
Be aware you might get into hiccups with gas - they can get out of tune - easy all you need is carbon tester and exhaust tester to fine tune etc, you may have problems filling up on hot days, problems starting up on cold days, heads may go sooner than normal petrol engine, at the end of the day it comes into a price.
Cheers
AP

all the maintenance cost, heads not lasting, get out of tune

Is this old school comments ? From my experience maintenance is less involved, less frequent, less costly - only hear of some commercial vehicles where the beast is heavy loaded all the time and engine is working harder most of the time - that engines and heads suffer as for getting out of tune - by the time some of these systems get attention they are old and have not had or needed attention for years. I do dislike the O2 sensor control boxes of the IMPCO systems as have not had to understand them or set them up but had one in yesterday EF Falcon that was a 1997 install, 300,000km on it and suffered a backfire blowing up the plastic air filter box. New plugs & leads and air box , start 'er up on petrol, switch over to gas and she is running sweet. A test run with tail pipe analyser on it showed the ancient never maintained or replaced componentry was still running stoich on idle and cruise, expected readings for light and hard acceleration.

It is a good idea to replace plugs and leads more often, but hardly extra maintenance.

Then you do get some factory dedicateds that just bloody stop in traffic for no reason, but suspect it is drive by wire stuff not gas supply

I do get a tickle when I see the older spud on systems using an exposed air filter hanging off the mixer and they look to be never changed, going dirty aged brittle looking paper element. Filter always loooks like never been replaced since conversion and likely due to never going back to installer, never to a gas mechanic and other mechanics fearful of pulling it apart to fit new filter - nt working again on assembly

and just what is a carbon tester ??

As for mounting a donut under the bonnet - needs four solid mounting bolt holes in the sheet metal or an approved bracket to bolt it all to , cut a big donut bulge out of the bonnet maybe