Comments on: LPG a good alternative fuel

By: Mark Farenden

Mark Farenden — Mon, 15 Feb 2010 05:05:36 +0000

Hi Guys, Size of tank, distance per tank, all garbage. What matters, my C20 Chev pick up with 307 V8, wheatbelt and back filling up in Sawyers valley every time, $80 petrol, same trip same servo, $36 on LPG. Wifes AU11 costs around $7 per 100k on LPG, while using less litres costs $13.20 per 100k in unleaded. Distance versus the buck is all that matters. I admit when I come up Greenmount hill with the Ford pulling tandem trailer and pine logs, I switch to unleaded as it does have ever so slightly more calories, if you like, this would be the only time I would change to the dearer stuff. My son used our Ford when his 600cc Mira was off the road. At 6 litres per 100 it was 20 cents per 100k dearer than AU11. We have had 5 vehicles on LPG and would never consider buying another petrol car. The Chev was but always planned on the conversion. Now the engine is very tired, a new one with higher HP 350 is going in, dedicated gas built, will update figures after.

By: Mr Brooksy

Mr Brooksy — Sun, 06 Dec 2009 23:12:33 +0000

Just wondering if you have ever heard of Vapor Injection LPG or the best systems available now in Oz, Liquid Injection LPG?
Much better fuel economy than the old mixer system but still not as good as petrol (vapor), similar L/100kms as petrol (injection).
Little drop in power (vapor) gain in power (injection) for some cars.
Granted you lose boot space, but in larger cars, its less of a hassle.
The only real world issue apart from the cargo space issue, I can think of is that in central Australia LPG isn’t really available like petrol and diesel. But 90% of the Aussie population can access it pretty easily.
Oh I just thought of another, cost of conversion is higher for both systems, but you get what you pay for right?

By: Mr Brooksy

Mr Brooksy — Sun, 06 Dec 2009 22:59:45 +0000

LPG is the reason we just bought a second hand V8 BA Fairmont Ghia. We got rid of the cramped little 99 Laser in favor of the big comfy highway cruiser, and with systems like vapor injection and liquid injection LPG systems out there, we will easily save on our fuel bill compared to the little buzz box. Heck it will be cheaper than many 4cyl cars!

Performance motoring on a budget, heck yes! Its just a shame that too many people have biased opinions about LPG being unsafe etc. If they saw it for what it is now, maybe out local car manufacturers would have a higher ratio of LPG to Petrol cars out there already, and allow us to still drive big beautiful cars instead of cramped matchboxes especially for guys and girls as tall as I at 6 feet 6 inches, or 199cm!

By: Andrew M

Andrew M — Sun, 06 Dec 2009 22:15:08 +0000

Yep thats true, I didnt point it out because for some reason they often run rough when switching back to petrol

By: PB

PB — Sun, 06 Dec 2009 12:11:43 +0000

The latest LPG systems are injected systems (Vapour or Liquid) thus do not have a mixer to restrict air flow.

By: Andrew M

Andrew M — Sun, 06 Dec 2009 09:20:16 +0000

Reply to cons……..

1 unless dedicated
But still more space than downgrading to a hatchback to save fuel dollars

2 Unless a decent dedicated system
Wouldnt really put a conversion on a ferrari, and power and torque is still acceptable, saving $ is the aim of the game.

3 Yep, use slightly more L/100k, but still half the price.
once again a decent LPG dedicated system should address that.
LPG tanks are also bigger to accomodate the more L required to do 100k’s

4 Fair enough, an extra tank will indeed add extra weight

5 Poor maintainence or use will cause problems (like anything)

6 Yep, do some research and get a decent system and decent installer.
not really the fuels fault if you want to be cheap

7 Yep, Ive heard of many that run rougher on petrol after running LPG.

By: Andrew M

Andrew M — Sun, 06 Dec 2009 09:08:53 +0000

Yep,
It was called a dedicated LPG Falcon, and its not mythical.

When Ford first came out with dedicated LPG in the AU series, the LPG model not only had more torque than the petrol version, but it also reached it lower down in the revs.

Over the years Ford has progressed/advanced/invested in the petrol version to a point where the LPG was neglected.

Now once the E-Gas gets an injected gas system to the equivalent of EFI (which is penned in for next year), Im sure we will see the LPG modelgain the edge in the torque stakes.

I hear what you are saying about the motor needing to be tuned, but the Falcon LPG motor is just that.
The E-gas motor does infact gain a different piston set up and different tuning as you suggest. I think its a damn credit to LPG (or the E-Gas motor) that with the old school tech, it still comes pretty close.

Early gas conversions were well off the pace, ill agree on that.

In driving LPG vehicles, I find that the biggest difference is not what power it does or does not have, but rather notable is that they dont seem to rev as high as petrol motors.

So go and follow the time line of the E-Gas and you will see even the old tech was able to punch out torque figures above what the equivalent EFI petrol could

By: Robin Graves

Robin Graves — Sun, 06 Dec 2009 08:40:51 +0000

Every LPG vehicle I have driven is down on torque and power. If its a dual-fuel vehicle, this is even more so. Dedicated LPG ‘can’ have equal torque as a petrol version if the compression ratio is made higher (new pistons and/or head shaved), different camshaft and proper tune on a dyno, but has anyone ever seen this mythical beast?

By: Robin Graves

Robin Graves — Sun, 06 Dec 2009 08:37:27 +0000

PROS
o cheaper to run
o better resale $$$
o claimed to be cleaner

CONS
o Loss of cargo space due to the tank
o loss of power and torque while on gas
o less km per lire from gas than petrol, but the gas is cheaper
o extra weight
o can have detrimental effects on fuel pump (petrol) if not run on petrol often
o some installs can be bodgy, unsafe and ruin Nissan warranty
o can reduce power while on petrol too as the mixer is a restriction.

By: Seo

Seo — Sat, 05 Dec 2009 23:09:32 +0000

<<2nd. photo shows a blue coloured LPG [Shell only] gun/nozzle