Outer Limits 4x4 Board

Has this been done b4? been thinking of alternate ways for running a sierra. would do away with a carb altogether and just run a throtle body.

Gas tank would replace the existing petrol tank

is only a thought.

i reckon a 4cyl engine on gas would be a bit gutless... and to replace the existing fuel tank its not going to hold much gas, and it would get smashed to crap on rocks n stuff...

all that said i'd be very interested if anyones done it and is happy with it, cos i have thought of it myself.

lpg would do away with any probs with angles associated with carbys and the lpg tank would be alot stronger than the petrol tank so should withstand the rocks better. i would also be mounted higher up in the chasis.
B4T

yeah but you need an LPG tank 50% larger than your current fuel tank to get the same amount of mileage... and you still need a fuel tank too =)

my greatest concern would be the power loss though.

alien wrote:yeah but you need an LPG tank 50% larger than your current fuel tank to get the same amount of mileage... and you still need a fuel tank too =)

my greatest concern would be the power loss though.

If you were wanting to run lpg as the primary fuel then you'd advance the timing to suit and wind up with more power than on petrol though. Lpg is higher octane, the power loss simply comes from comprimised tuning between the two fuels.

Of course you would see a drop in power on petrol then but you'd only be using it in the few cases lpg wasn't available.

I wouldn't chance the tank being stronger than a pertol tank though cause if it gets punctured the results will be MUCH worse

U don't need the fuel tank as well. Tune it for straight gas and u should get more power. If u got a ute or tube back u can mount a decent tank behind the cab.

a mate ran dual gas tanks on a 1.6 tbi in a diashatsu F20. with the supercharger went v/nice and reasonable economy.

Worst prob is u can't carry spare fuel.

cheers

Nic

gonads

well now big zook pretty sure his 1.3 was on straight gas

Yep, his conversion was set up to use forklift bottles, swap out, swap in.

thats a fantastic idea! be very cool to keep a small spare tank on board like a jerry can.

but then you run more of a risk of explosion... their like 50kg's of C4 sitting 1 foot away from ya...

Thats if worst comes to worst

lpg you can also run a higher compression causing better burning, i run a dedicated gas vehile all day and evry day and they arent that likely to go bang.

Flat_Matt wrote:but then you run more of a risk of explosion... their like 50kg's of C4 sitting 1 foot away from ya...

Thats if worst comes to worst

The only way to get a lpg explosion is to mix in O2 by preference or air..... in the correct ratio in a confined space.

You can shoot LPG bottles with incendary rounds from a M82A1A (50 cal snipers rifle) and they don't go boom. They just hiss a lot and freeze everything nearby as they spin round uncontrollably....


They tried to cause a gas explosion on mythbusters in a portaloo, did not really work at all until they added 20% gas to pure O2.

This is really starting to sound awesome...

so on a carby powered zuk, how do you get the gas in? surely its not just a case of replacing the fuel lines?

i like my weber =P

Normally 2 ways, vacuume operated gas carb like a normal carb, or constant flow.

There was an awesome writeup of these somewhere on the board.
http://www.outerlimits4x4.com/PHP_Modul ... t=lpg+carb

There is a 3rd method gasseous vapour injection, all gear comes from gasresearch in Aust. but probably worth more than 2 zooks combined.

Some more reading http://www.outerlimits4x4.com/PHP_Modul ... arb+adjust

I was considering LPG so keep post updated on progress, as im sick to death of my sierra dying on steep angles.

i was of the understanding that LPG tanks for vehicle use out to be able to survive a rear ended collision.... sureley thats strong enough vs rocks?

I don't think you nessecarily need 50% more capacity becaause it uses %50% more fuel. Just make sure it's tuned and configured for extra power efficiency

yeah but the 50% bit is also because of the usable gas that is in the tank.

don't quote my figures at all but

100 L tank only get 80L of usable gas in it.

thats what I have been led to believe.

I think 50% is a bit too much of a loss. even with the k's per litre argument and the usable gas.

enjoy ashley

Germo is correct, Tanks will only fill 80% of total capacity from a LPG gas bowser, you will have issues if you manage to overfill anyway.

this is not something im doing right now but could do in the future.

you should be able to fit a bdecent size tank underneath where the existing petrol tank is . especially if you have a BL. i have been thinking of using 2 of the 3 tanks they use in falcon wagons. they have a tripple tank setup (some did). they fitted in the square sub-floor of the wagon. each tank held about 20-25ltrs i think.

would use a system similar to what is used on hilux's and work vans. convertor supply'n a simple mixer.

HMM just need some $$$$to make it happen

LPG is pretty safe if you look at the number of LPG powered vehicles on the road. Even seen a number of completly burn't out shells with gas that didn't go boom!

There are all different types of tanks out there and depending on what you want you can mount the in different ways. There was even a tank that was in the shape of a spare tyre to fit in the spare recess of car boots.

My XF falcon gets 320kays per 62lt gas. I have my car tuned to favor gas and find little difference between gas and petrol. My car is carby powered just like a zook.

All you would need is a gas tank to suite your mounting location, converter, gauge and some type of intake trumpet over the carby to feed the gas in. There are plenty of wreckers with plenty of bits lying around to be able to make a kit out of. Kit should not set you back more than $300 second hand with a tank that has at least 5 years left on it. Then you find a fitter to fit and certify for around the $350 and you have a zook that will run on all angles and cost stuff all to run.

Food for thought

jtraf wrote: There was even a tank that was in the shape of a spare tyre to fit in the spare recess of car boots.

I can just see it now , a circuler gas tank hanging off my tailgate mounted on my wheel carrier.

Still in a normal car this sounds good till wait for it... where do you ut the spare wheel?

My XF falcon gets 320kays per 62lt gas. I have my car tuned to favor gas and find little difference between gas and petrol. My car is carby power

Food for thought

What size engine is that (3.9!?) cause if you math it out to a 1.3l that's like one third the capacity so easily twice the distance?

I Suppose if you went big gas tank and maintain a small 5-8lt Auxillary petrol tank you could make it work. On extended trips away from lpg stations you could limp along toping up with a 20lt jerry can every 80-100km. (This happening infrequently if you are getting 450km or so on said 62lt tank)

i've had a gas mishap whereby the tank had to be emptied into the atmosphere. the fireys just had a hose on standby and let the gas dissipate naturally. it was pretty safe really. lpg rocks!

Yeh you would have to be pretty unlucky for it to explode in flames, because as mentioned before you need a reasonably accurate fuel/oxygen ratio.
I would be more worried about shrapnel from the tank if it did get pierced.

LPG seems to have more myths about it than Zooks (ever been told Sierra's were discontinued because they roll too easy)

I have had LPG powered vehicles, both dedicated and dual fuel since 1989. The economy is great.

"LPG vehicles don't have as much power as petrol" I don't believe it, I have never put two like vehicles on a dyno, but if there is a difference it is not noticeable to the driver.

"LPG may be cheaper but you do not get as good a mileage out of it" Consistently better mileage from LPG so long as the vehicle is tuned properly.

"LPG vehicles cost more to maintain" I think this may come from the fact that you require a gas certificate annually to register your vehicle, however the $25-40 for a certificate a year is nothing compared to the cost of maintaining a petrol engine (actually for the 100,000 km a year we ran we would have spent more than this on fuel filters alone). Not every mechanic can work on gas vehicles, so less "backyardies" or unskilled staff meddling with your vehicle, the good mechanics cost no more than bad ones. Less likely to get a dodgey gas mechanic they make their living from servicing work vehicles, rip off one taxi and you can kiss your business goodbye.

"LPG kills your engine, they don't last" To dispell this myth have a look at the odometer on a taxi or courier van and ask if that is the original engine.

"It might be okay on a big engine but not on a four cylinder" I ran Ford Econovans with 2.0lt FE carby motors. Ran forever, carried more than decent loads, towed trailers, regularly offroad. I got great economy, plenty of power and at least 350,000 km from an engine and this was from my first one which I hardly ever did anything to maintain (read cheap as, went 50,000kms between oil changes. I desreved to have it die a lot earlier)

"LPG vehicles explode in collisions" Yeah and all 4WDs are huge battle trucks and driven by angry fat men with small dicks who ram people with their bullbars. One of my vans was rearended at speed relocating the tank forward and up so that it sat over the diff. I awsn't in the vehicle but the driver and fireys both tell of how onlookers stayed away in fear of the tank exploding, and laugh about it. Apparently there is greater risk of ignition from a leaking petrol tank.

" you need to retain petrol for when you can't get to a service station with LPG" Ever heard of a fuel guage. Very few service stations don't carry LPG.


I am an advocate for LPG vehicles, I caould keep going with the benefits, but here are the only downfalls I have noticed.

Extra cost on initial install, recouped if you do reasonable mileage or as Jtraf stated buy second hand, should be lots at wreckers.

Spare wheel. Most manufacturers don't design their vehicle to carry a second fuel tank, so if going dual fuel the spare is often replaced by the tank. Dedicated LPG overcomes this.


This is just my opinion and observations from many years of happy motoring with LPG to balance the repitition of unfounded myth.

the idea of putting a decent size tank where the existing petrol tank sounds like the go and if you want then mount small auxillary tank under the passenger seat like in the toyota FJ40's. Lpg tank would need a stone guard and a heat guard on exhaust side. wonder what size tank would fit???

Tanks are limited in size due to shape - theoretically any shape is possible but the weight of the structural bracing rules out most things besides cylinders and donuts/toroids.

There are ones designed for ford wagons that are like 3 cylinders side by side.

You could run multiple cylinders of different sizes but then you get issues to do with the connections between tanks. Plausible but increase risk - the lines are much easier to damage or leak.

LPG tanks are substantially heavier too.

I've thought more than once about the BBQ style LPG reserve tank and can't see any reason why it couldnt be done a-la subtank of a Prado/Patrol etc

So has anyone got any recent experiences with zooks on gas?

With the price of fuel, i am about to give up on my 32/36DGAV, and am thinking straight gas.

Does anyone know how well a tank will fit under a LWB (body lift possible if necessary)

Have also seen in the US forklift bottles used, does any one know if this is legal in aust. ?

Cheers, Pixie

i've come across sierra's with gas.the only drama is range, and by that i mean not being able to carry a jerry.not all servos have gas. my 2.0 litre v6 and 2.7 v6 vitaras are both on gas and i think i have only lost about 50 k's to a tank if that, and the gas tank is the same size as the fuel tank. oh, and when considering gas get it done right, this is one product you don't want installed by a back-yarder.

DiddyZook wrote: (ever been told Sierra's were discontinued because they roll too easy.

Sorry for the Hijack, but in the US maket, that's exactly why they were discontinued.

Gas is for forklifts and BBQ's.

Steve.

i always felt you could make a limp mode petrol tank over the driver side rear wheel arch. If made a custom tank it probably hold about 4L, sure you may only get a 35km range but combined with a jerry you could get by when you are caught out. The rest comes down to fuel management(like filling up whenever you can rather when you starting to need it) andplanning your trip (long trips like sydney to brisbane you call ahead to ensure they stock lpg before leaving) Unless you live in an area that has one servo in a 100km radius

I'd be curious to see how much it cost to get custom tanks to sit under the door. I Calculated that you could have a 20lt cylinder between the front and rear spring mounts on my WT which did not sit any lower than the chassis rail. If you had one on each side that would be 36lt (allowing for 80% capacity) and you could have them as an A/B set up. Two seperate fillers, when one tank empties you switch to the other (and still retain the stock fuel tank or go for a Long range ' C' Tank!)

A/B Set up with say 7km/l would give a 250km range (with electronic ignition and engine mods you may be able to put that in the 300km zone)

ahh the projects yet to come