[Damo]

Any thoughts on what size tank would fit in a Sierra? I'm talking dedicated LPG only system replacing the stock tank. If you re-routed the exhaust I think you could get a 60-ish litre tank in there (360 dia, 700 long)

[TZAR]

what about the falcon multi tanks Can't find a link but they had about three small cylinders that fitted under the rear boot floor

or this ugly number. You could build an under floor storage system

[ajsr]

I was thinking the same myself straight LPG that is.
A mate that does gas seems to think he can get at least60 maybe 70 useable litres where the fuel tank was, as I have a body lift but Ill have to move the exhaust a bit.
The reason I'm looking at it is no more hesitation or bogging/stalling on hills LPG will run upside down.

[joeblow]

oh yes, lpg sounds good, but i've had some drama getting my two vits right. just beware.

[ajsr]

what setup are you running/trying joe?

[Damo]

ajsr wrote:

I was thinking the same myself straight LPG that is.
A mate that does gas seems to think he can get at least60 maybe 70 useable litres where the fuel tank was, as I have a body lift but Ill have to move the exhaust a bit.
The reason I'm looking at it is no more hesitation or bogging/stalling on hills LPG will run upside down.

Yeah moving the exhaust is the biggest PITA of replacing the stock tank with LPG tank. I think 50 usable litres is going to be closer to the mark though, and once you factor in that you use more LPG than petrol for the same mileage, you're looking at roughly the same range from a 50 usable litre LPG tank, compared to the stock Sierra tank.

[11_evl]

must be a bit of a bit of a trend ATM. im doing the same thing. im building the 16v now. (chasing a head gasket if anyone in bris has one) i will be running it on straight LPG using a replacable forklift bottle mounted in the back. i think they hold 46 litres and i will have a spare for long weekends. my car is not a daily driver!!
im trying a very basic system comprising of a landi converter and venturi style throttle body. should be right for what i want.

JOE. what setup are you running

[ajsr]

yeah mines a basher only. I thought about the fork bottle idea as well but I'd have to run it in the cab as in hard top and im tryiny to keep the weight low in the car.
The advantage to fork bottles is they are staight propane not a shit 50/50 mix or worse of butane so more power.

[Damo]

11_evl wrote:

must be a bit of a bit of a trend ATM. im doing the same thing. im building the 16v now. (chasing a head gasket if anyone in bris has one) i will be running it on straight LPG using a replacable forklift bottle mounted in the back. i think they hold 46 litres and i will have a spare for long weekends. my car is not a daily driver!!
im trying a very basic system comprising of a landi converter and venturi style throttle body. should be right for what i want.

JOE. what setup are you running

Post up your progress, i'm sure i'm not the only one interested.

I'm thinking of putting LPG on my project motor, g13 with 16v head + turbo.

[11_evl]

ATM i have an empty engine bay and an almost build g16 and 16v head. i want to use the baleno manifold but cant find info on the thermostat as yet.

[Rockhopper]

If it's in a basher forklift bottles should be fine, but I'm pretty sure it will be a very big no no fitting one to a road registered vehicle. I'm licenced to fit LPG to forklifts and industrial equipment (but not cars) and I was thinking that a Landi system off a 1.5 - 2.5 tonne Toyota forklift would work great on a Zook. The Toyota engines are a 2.4 litre so the convertors are more than big enough to power a zook and they are very reliable.

[TZAR]

ajsr wrote:

The advantage to fork bottles is they are staight propane not a shit 50/50 mix or worse of butane so more power.

Forklift engines are designed to drive a hydrulic pump and run at a set range of revolutions.

The reason autogas is a mixture is to allow the engine to run at different loads, and also has different tempuratures that affect the two gases. The gas is constantly changed throughout the year to allow for different tempuratures.

So its not basically just slapping some gas down the carby shit like people think. It is a science thats why they pay HUGE money to petrochemical engineers to make the best product they can.

[Damo]

11_evl wrote:

ATM i have an empty engine bay and an almost build g16 and 16v head. i want to use the baleno manifold but cant find info on the thermostat as yet.

Just been looking at mine tonight, the Swift TBI manifold should work OK but will have the same thermostat problem as you. If you look at the head it has a water outlet that would feed into the thermostat housing, you should be able to cut a hole in the manifold flange to line up with that water gallery, then cut off the part that the thermo housing bolts to from another manifold and have it welded on. Clear as mud?

[ajsr]

TZAR wrote:

ajsr wrote:

The advantage to fork bottles is they are staight propane not a shit 50/50 mix or worse of butane so more power.

Forklift engines are designed to drive a hydrulic pump and run at a set range of revolutions.

The reason autogas is a mixture is to allow the engine to run at different loads, and also has different tempuratures that affect the two gases. The gas is constantly changed throughout the year to allow for different tempuratures.

So its not basically just slapping some gas down the carby shit like people think. It is a science thats why they pay HUGE money to petrochemical engineers to make the best product they can.

tzar why is my friend who is a engineer designing new gas systems telling me otherwise.A very talented man who's been designing gas systems for about 15 years now.

I used to run a 1.8 turbo datsun 1600 grag car setup be this friend of mine using straight LPG now this vehicle would detonate on propane/butane mix at around 15lbs of boost but on straight propane was capable of 19 -20 lbs and 30 horses more with no detonation at all.

he tells me the main reason that the two are mixed is that butane is far more plentiful however that the quality is not good enough to run a resonably high perfoming motor,therefore the mix it.
looking forward to your ideas
cheers andrew

[Damo]

Damo wrote:

ajsr wrote:

I was thinking the same myself straight LPG that is.
A mate that does gas seems to think he can get at least60 maybe 70 useable litres where the fuel tank was, as I have a body lift but Ill have to move the exhaust a bit.
The reason I'm looking at it is no more hesitation or bogging/stalling on hills LPG will run upside down.

Yeah moving the exhaust is the biggest PITA of replacing the stock tank with LPG tank. I think 50 usable litres is going to be closer to the mark though, and once you factor in that you use more LPG than petrol for the same mileage, you're looking at roughly the same range from a 50 usable litre LPG tank, compared to the stock Sierra tank.

It's probably gh3y to quote myself but I don't care.

I did some more measuring tonight and in the back where the tank is the distance between the chassis rails is about 750mm. On this page there are some tank sizes, and the 62 litre one (700 long, 360 dia) would be the biggest you can fit in there. Front to back size is about the same as stock fuel tank but it would hang a little lower than the stock tank. With a body lift you could move it up a bit.

Now if only I can find something in that size 2nd hand...

[ajsr]

early commodore may be close they fit between the rear shock towers and were around 60 lt so maybe close.
cheers andrew

[TZAR]

Why are Butane and Propane used in combination?

While butane and propane are different chemical compounds, their properties are similar enough to be useful in mixtures. Butane and Propane are both saturated hydrocarbons. They do not react with other. Butane is less volatile and boils at 0.6 deg C. Propane is more volatile and boils at - 42 deg C. Both products are liquids at atmospheric pressure when cooled to temperatures lower than their boiling points. Vaporization is rapid at temperatures above the boiling points. The calorific (heat) values of both are almost equal. Both are thus mixed together to attain the vapor pressure that is required by the end user and depending on the ambient conditions. If the ambient temperature is very low propane is preferred to achieve higher vapor pressure at the given temperature.

Butane and propnae have the same heat range meaning they produce the same amount of energy from the same amount of gas.

more later things to do

[Rockhopper]

TZAR wrote:

ajsr wrote:

The advantage to fork bottles is they are staight propane not a shit 50/50 mix or worse of butane so more power.

Forklift engines are designed to drive a hydrulic pump and run at a set range of revolutions.

The reason autogas is a mixture is to allow the engine to run at different loads, and also has different tempuratures that affect the two gases. The gas is constantly changed throughout the year to allow for different tempuratures.

So its not basically just slapping some gas down the carby shit like people think. It is a science thats why they pay HUGE money to petrochemical engineers to make the best product they can.

I have been led to believe that butane is to LPG what ethanol is to unleaded. It is added to LPG so the service stations can make more money, but burns a lot quicker than straight propane, which is why I used to find when I owned an LPG powered GQ Patrol that I used to get better fuel economy when I filled up at my local Caltex, than when I filled up at JoeBlow's Servo down the road.
(Sorry JoeBlow, not trieing to tarnish your name or anything )

[11_evl]

fuel wise, i will just fill the bottles at the servo for the convienance. so that should keep the ratios in spec as you say TZAR. the only difference mine will be is its simplicity. i wont have a seperate computer, altho i may grab one of an old cab at the wreckers later down the track, to control mixtures to a more fine tune. it just wont be needed at this stage..
the landi converter found on most of the forklifts are meant to be able to run most motors including V8s. they can supply anything that is needed. im looking into the mods to turbo charge as well. the LPG course i did for work didnt cover turbo but ill nut it out:)

[TZAR]

Okay back its mainly to do with the vapourising tempurature (liquid to gas)and the fact the closer you run either of these gases to its vapourising tempurature the difference it will be.

This affects the pressure of the gas as it turns from a liquid to a gas. Propane will have a higher pressure
BUT Butane has a lower ignition tempurate

The gas itself has really very little difference
Propane delivers about 21,600 BTUs per pound,
Butane will put out about 21,300 BTUs per pound
BTU = British thermal unit.

1 btu = 1 055.05585 joules

I understand that is super duper engines this may produce more power, but really gasoline will create more power than gas any day anyway so whats the point.

And remember its a suzuki, a 1.3 engine and we are talking mega power mods to it. Are you changing combustion chamber swirl patterns to allow for the gas? are you changing how the exhaust flows?

Or are you just slapping on a turbo and gas? Like you said its a weekend toy, so why do you need the extra power?

[Damo]

ajsr wrote:

early commodore may be close they fit between the rear shock towers and were around 60 lt so maybe close.
cheers andrew

Good tip, thanks for that.

[11_evl]

ummm. i dont think anyone said anything about going LPG to increase powerr or to shoot for a better power increase over stock....??

im going LPG because i looked at my ECU wiring and thought F#CK THAT. than thought about the shit carby that i have spent WAY too many hours cleaning taping reving, just generally not working and thought why not try LPG.
it cant be that hard can it. they work so simple on the forks at work.
as for the turbo. thats just an after thought i mite muck with cus i have the manifold, cooler, turbo and piping. if it work it works, if it blows a motor ill build another. im about getting out theye with trial and error.
thank you we do appriciate your wealth of knowledge and i will read back over it as i come to problems at that stage.

no the combustion chamber is 16v suzuki original.
no im not modifying the exhasut other than std manifold, commodore cat, hot dog and can of coke if i can still fit past my coils.

another reason why i want LPG is so i can get rid of the vit tank and move the rear diff furher back.

you say remember 'ITS A SUZUKI'. do you mean its a sierra or its a suzuki motor?

sorry about the long post

[Damo]

11_evl wrote:

ummm. i dont think anyone said anything about going LPG to increase powerr or to shoot for a better power increase over stock....??

im going LPG because i looked at my ECU wiring and thought F#CK THAT. than thought about the shit carby that i have spent WAY too many hours cleaning taping reving, just generally not working and thought why not try LPG.
it cant be that hard can it. they work so simple on the forks at work.
as for the turbo. thats just an after thought i mite muck with cus i have the manifold, cooler, turbo and piping. if it work it works, if it blows a motor ill build another. im about getting out theye with trial and error.
thank you we do appriciate your wealth of knowledge and i will read back over it as i come to problems at that stage.

no the combustion chamber is 16v suzuki original.
no im not modifying the exhasut other than std manifold, commodore cat, hot dog and can of coke if i can still fit past my coils.

another reason why i want LPG is so i can get rid of the vit tank and move the rear diff furher back.

you say remember 'ITS A SUZUKI'. do you mean its a sierra or its a suzuki motor?

sorry about the long post

So if you keep the stock ignition system it should work, but is there much gain in changing that? I'd think that giving it more timing would be a good thing, which was why I was thinking about using my megasquirt for the ignition side of things, fully mappable sequential ignition with 4 coils.

[TZAR]

11_evl wrote:

ummm. i dont think anyone said anything about going LPG to increase powerr or to shoot for a better power increase over stock....??

sorry another poster was after power, not refering to you. Max power from gas is hard work.

11_evl wrote:

you say remember 'ITS A SUZUKI'. do you mean its a sierra or its a suzuki motor?

This is my comment to all super power mods on a suzi. The suspension and braking systems are not designed to be driven like a race car.
My favourite saying is "I think that you should never try to make a goat into a racehorse. It wastes your time and annoys the goat."

I think your idea will be a fantastic one. simple yet effective but as all things has its ups and downs.

Gas is good as it works on all angles but so does injection. Injection is easier to turbo later as you can use a different cam profile to help sweep the chambers of all spent gases without blowing fuel out the exhaust

It is simple system but lots of research is needed on the ups and downs. You as a licensed fitter have the understanding of what can go wrong. I hope you get an awesome system happening but when you show others can you go into some in depth detial of what you have done so that they understand there is a right and wrong way to do things.

[ajsr]

normal LPG (auto gas ) will work fine on any motor setup turbo, supercharged or NA. the reason im a propane fan is more power(yes it is fairly marginal)
the main reason is that as anyone here who owns a gas car knos ,gas mixtures vary between suppliers and servo's.your car may run great when fueled from one servo and just ok from another.the reason behind this is how the vehicle is tuned, when they convert it it's suit the mixture the gas guy put in your tank when you run another mix it may not run at 100% efficency.
propane is a constant therefore allowing a better tune and more power, sometines it's marginal but sometimes its quite noticeable.
anyway gas is good and works really well on turbos as the octane rating is around 108 on LPG dependant on mix.
cheers andrew

[TZAR]

Here Damo is what I meant about multi tanks



would be easy to put under the floor

[Damo]

TZAR wrote:

Here Damo is what I meant about multi tanks



would be easy to put under the floor

I think that's the one they use in Rovers isn't it? I thought about that but the diff is in the way. Could put it inside but couldn't put seats in as well. Replacing the stock tank is the best way to go I reckon.

[11_evl]

damo
i was mucking around with mine last nite and at this stage im having almost no electrics at all. i drilled out the bottom of the baleno angle drive to suit the stock 1.3 dissy. so im just going to run stock dissy and coil and see how it goes. that way ill have all the factory ignition advances, no need for an ecu.
i did find a tank like the above but i have not done any measurements.
BTW a little extra available power in a suzuki is not a bad thing is it.

[Damo]

11_evl wrote:

damo
i was mucking around with mine last nite and at this stage im having almost no electrics at all. i drilled out the bottom of the baleno angle drive to suit the stock 1.3 dissy. so im just going to run stock dissy and coil and see how it goes. that way ill have all the factory ignition advances, no need for an ecu.
i did find a tank like the above but i have not done any measurements.
BTW a little extra available power in a suzuki is not a bad thing is it.

It should run, I just think there's more power to be had if you can play with the ignition. But i do appreciate the simplicity of the stock system, much neater. I just happen to have the Megasquirt already so it's a no brainer.

[11_evl]

For sure if you have it all there.
What stage are you at with your gas setup?