LPG injection systems - Looks interesting!

[pundit]

As I'm spending $5k AUD ($4k USD) per year (at current prices) on fuel, I'm beginning to seriously consider switching over to LPG (Liquified Petroleum Gas). Of course the catch is while LPG is around one third of the cost of petrol (gasoline for our Yankee friends ) it generally comes with around a 10-20% power loss and a 15-30% decrease in fuel efficiency (MPG). However although LPG has a slightly lower heat value than petrol, LPG is a very high octane fuel and can take advantage of both high compression ratios (12:1 or higher) and/or increased ignition timing advance.

Traditional 'old' technology LPG systems have often literally dumped gas into the inlet manifold in a not very well metered fashion with manifold backfires being a common and often damaging consequence. Newer LPG injection systems are now appearing on the market (SGI Sequential Gas Injection) utilising special injectors designed for LPG. While most of these systems require custom fuel delivery electronics a new system (GTI Stealth) is able to be adapted to utilise the vehicles factory ECU and engine managment system to directly control the LPG injectors. To me, this looks interesting as it allows the existing vehicle electronics to be maintained and as the LPG delivery is better managed it offers improvements in both power and economy over conventional LPG systems.

Has anyone here had any experience with LPG injection systems?

Hmmm... how about a Megasquirted, turboed LPG install!?

[rob101]

how many kilometers are you doing a year? and what is your average fuel consumption. Realistically how much longer are you going to keep your current car?
If you haven't thought about any of this yet i urge you to think about it.

LPG systems aren't financially what they seem for example say you're using an average of 14L/100 km on petrol so that means 18.2L/100 km of LPG up here fuel is 50c/L for LPG and $1.25/L (when you buy on tuesday as this is always when you get the lowest price) and an average distance per year of 25 000 km (fairly usual) i would expect that kind of installation to be $3000 at least. you're going to be driving for one and a half years before you break even. and if you think thats bad remember LPG will have excise on it after mid 2008 (i here). I would price a typical installation of LPG injection, i would expect my 3000 estimate is on the low side (thats about what it costs to do a mixer ring type setup on a 4wd). not to mention the limited availability of LPG outside the cities.

so...... i don't really know if its worth it really. Just buy your fuel on tuesday unlike the great myopic hordes who buy it late in the week and pay an extra 15c/L (last week i bought 98 octane on tuesday afternoon for 5 c less than price of 91 octane the next afternoon)

anyway gas research has a good website I don't want to dissuade you as I too would like to play with LPG. But there are certain financial realities one must face when examining LPG conversions.

[Paul in NZ]

how about the fact that at some time petrol will be even MORE expensive.Will LPG track the price of petrol?

[rob101]

how about the fact that at some time petrol will be even MORE expensive.Will LPG track the price of petrol?

yes because the demand for LPG is likely to rise around the world. and thus our own prices, as our market for LPG is deregulated as with petrol. I am not sure that the price of petrol will rise that much. it is interesting to note that the previous 70c/L situation was well below where it should have been if you look at inflation. and we aren't yet at the price levels that the oil crisis bought about.
but...... people have to whinge about something right?

[pundit]

how many kilometers are you doing a year? and what is your average fuel consumption. Realistically how much longer are you going to keep your current car?
If you haven't thought about any of this yet i urge you to think about it.

LPG systems aren't financially what they seem for example say you're using an average of 14L/100 km on petrol so that means 18.2L/100 km of LPG up here fuel is 50c/L for LPG and $1.25/L (when you buy on tuesday as this is always when you get the lowest price) and an average distance per year of 25 000 km (fairly usual) i would expect that kind of installation to be $3000 at least. you're going to be driving for one and a half years before you break even. and if you think thats bad remember LPG will have excise on it after mid 2008 (i here). I would price a typical installation of LPG injection, i would expect my 3000 estimate is on the low side (thats about what it costs to do a mixer ring type setup on a 4wd). not to mention the limited availability of LPG outside the cities.

so...... i don't really know if its worth it really. Just buy your fuel on tuesday unlike the great myopic hordes who buy it late in the week and pay an extra 15c/L (last week i bought 98 octane on tuesday afternoon for 5 c less than price of 91 octane the next afternoon)

anyway gas research has a good website I don't want to dissuade you as I too would like to play with LPG. But there are certain financial realities one must face when examining LPG conversions.

Excise on LPG has been deferred until 2011... and will be progressively phased in @ 2.5 cents per year over five years until reaching a maximum excise of 12.5 cents per litre.... Cough, cough... "Mother should I trust the Government?"

http://www.esanda.com/common/pdfs/Fleetview12.pdf

I currently clock around 30,000kms per year @ an average of 14.5 litres per 100kms. The newer SGI (Sequential Gas Injection) systems are more efficient than the old systems. My recoup period would be approximately 12-14months based on a saving of $3,000.00 per annum (I'm EAT chipped and running premium unleaded @ around $1.40-$1.55 per litre) LPG down here fluctates between 40-60 cents per litre. Yes LPG will increase in price as demand goes up, but even taking all other factors into consideration (installation costs etc) LPG will still be a cheaper alternative for the next ten years after which none of us will be able to afford to drive any vehicle powered by non-renewable fossil fuels!

[rob101]

yeah, well get a quote of how much an install will cost. I think everyone on this board will be interested (myself included). I seriously think 3000 will be too little, but..... i simply just don't know, but assuming that this costs more than the mixer ring installs it going to be at least that much.
Oh they pushed the excise back thank god, from an environmental POV the sooner lots of people start using LPG the better. the difference in emissions is huge from what i've read. They already have a rebate on new LPG vehicles i believe.
personally i am going to probably get a new car in a couple of years (big boy will be at 300 000 km then )so for me its not really worth it

[Paul in NZ]

will you run a lpg tank in the boot pundit?

[pundit]

will you run a lpg tank in the boot pundit?

I'm not sure. If I go ahead with something like the GTI system I'll probably ditch the fuel tank altogether and just run external LPG tanks in place of the original.

Some of the new LPG injection systems can start on LPG from well below zero degrees so the need to use petrol for cold starting is no longer an issue.

I must admit, I'm not too fond of LPG tanks in the boot (er trunk) the or inside the passenger compartment as in some station wagons.

Just think, you could run a 12:1 compression ratio and with something like Megasquirt fine tune the system for the best efficiency.
With a properly setup system low end torque may even better than petrol.

[genphreak]

ECU, LPG and a SNAIL may be a good way to go?

[rob101]

ECU, LPG and a SNAIL may be a good way to go?

somehow i think that would defeat the purpose of saving money!
It'd be interesting to crunch the numbers of buying a corolla or matiz or echo for during the week AND having a e34 but only driving the e34 on select occasions.
either that or just buy a 750iL and run it on LPG
i think that would pay itself off in about half a year