This posting may be long and boring, so you may be excused if you choose to fall asleep in the middle of all of this.

Being mr average who does 20,000 miles a year and being mr average income wise, the price of fuel is bugging me more and more. That pyschological £1 /litre is now a reality on most areas.

Not for the first time, my mind has turned to running an LPG powered car, but two things have always put me off.

1) The cost of the conversion on a normal sized car of 1.6 to 2.0 litres will be a long time in paying off the initial investment. (Around £1600 +VAT)

2) The thought of converting a fuel injected car to what is effectively a carburettor seems like a terribly backward step.

I know that 15mpg behemoths like Range Rovers have always made sense on LPG, but I want a 40mpg car on LPG - 15mpg is 15mpg whichever way you look at it, and that's just wrong when you're doing decent miles.

(I know I could flog it and buy a diesel, but nobody ever bought a diesel because they really wanted one. If you did, please resign your membership of locostbuilders right now.

Anyway - enough babbling.

As a service to your good selves, Zil has been doing a bit of research and has come to the conclusion that fitting an LPG system yourself is not terribly difficult and that it can be relatively sophisticated and inexpensive at the same time.

Consequently I have discovered this system.

This system is available on ebay for the princely sum of £400 - clicky here

I have been in direct contact with the supplier in Italy and can confirm that this is for a complete system with the solitary exception of the bare tank.

The main attraction of this system is that it is true sequential injection which hooks up to your OBDII port and is self regulating after a very basic initial setting of the mixture via the display on the control.

Furthermore, Zil has also established that bare tanks are readily available from around £120 upwards. These are all brand new prices.

So - if you DIY in the Locost fashion your car will be running sequential LPG for around £520 instead of about £1600 + VAT.

Based on all of the above, my payback time is 5 1/2 months and after that my saving will be around £110 /month - if fuel prices remain static.

Well, we all know that won't be the case.

That is all, the above information may be of interest to one or two of you.

[Edited on 30/7/07 by zilspeed]

Looks liek a good price. The only thing I can think of is that you will definitely need to tell your insurer and they might get a bit arsy if you say "I have just done some homemade changes to the fuel system". At the very least, they would probably ask for some "independent expert" to verify what you have done, and they wouldn't do it for free, presumably. Also, would the insurance itself cost you more, as there are more bits to replace if you have a claim?

I've looked into this as well.

Some of them want an inspection, some of them don't. Some charge more, some don't.

Cost of an inspection starts from around £50.

admittedly i didn't read the links and only the 1st half of the post, but i thought doing a DIY lpg conversion was illegal...

Fortunately, you couldn't be more wrong.

The LPGA (the trade association) would have you believe that their way is the only way.

A quick google will confirm that there are loads of people out there doing it and suppliers more than willing to sell to them.

Did my range rover with an OMVL system, sequential injection LPG, insured with NU, they did not need and inspection and did not hike up the insurance cost.

Easy to do, inlet off and drill and tap for gas injectors, then it was just plug and play under the bonnet. Gas tank needs properly securing, if you get a round one to replce the spare wheel you still need to secure well.

As above, competent installer required, not trained expert as in do it yourself.

The only bit that concerns me on the kit is are the words "injection emulator", on my system you plug the car injectors leads into the ECU, these then feed back to both gas and car injectors and the ECU spoofs the injection of cuts through when on petrol, old vapour inducing systems had an "injection emulator", for sequential the gas is at a higher pressure, mines I believe 2 bar so a bit more research on this one IMHO, make sure its not an old vapour system with a different front end.

Regards Mark

[Edited on 7/10/07 by mark chandler]

Fair point Mark - it does indeed say emulation, but that is doen within the ECU. I believe that is really the same thing as 'spoofing' the standard ECU into believing that all is well with the petrol injectors. Whatever the case, I'm going for it.

The system is, vapour phase injection, which a quick google confirms is exactly the same as OMVL

Forgot to add - like yours, this system has a loom which the existing injector leads plug into and a new part which feeds the petrol injectors.

[Edited on 30/7/07 by zilspeed]

Hi we have a setup using a 7.4ltr chevey with single point injection.

Things that you have to also take into acount is that it is never quite as powerfull on the gas as it is on petrol upto 20% difference can be expected in the worsecase.

And also make shure you have a good local supplier of gas that dose it at the right price. And that you have a large enough tank to do a complete regular trip back to base on a full tank. The reason is that a good local supplier shoud be around 32p/L but once you are out on the road you will find that 48p-50p/L is the norm. This means that in some circumstances at that price it is not enough of a finacial saving to justify the oiginal conversion cost or take a long time to recuperate that cost. In ourcase at 49p/L it is cheaper to run on petrol but it is a big wagon and towing.

Just my 2p cheers matt

Do they do a system for diesels?

In answer to the various points.

Cheers Paddy - you're a good man.

Regarding local supply.

In my normal working day, I will be mostly in East Kilbride, Rutherglen, Hamilton or what is known as the clyde valley.
All three towns above have LPG suppliers.
The places we frequent at weekends are never terribly far away from LPG. And finally, my GPS can accommadate overlays which are available with LPG availability info.
All my calculations are based on having to pay 42.9p a litre at which point things make excellent sense.
Regarding performance, I'm sure that SGI will perform way better than single point gas.

Anyway - the kit and tank is now well and truly ordered. Kit £400, Tank £120 .
That tank is a little dinky 40 litre job which will fill to 32 litres (I have a Golf MK 3.5 Cabrio - no room for anything larger).


32 litres is £30 of petrol. I put petrol in 20 litres or so at a time, so I'm not losing anything there. And - I'm quite happy that my 32 litres will cost me under £14 as opposed to £30.

(Enough figure already - I'm even boring myself).






Just add a few drill bits, a hole saw and some boss white.

Regarding set up, I already have Vag Com on my oldest laptop and have checked all the outputs on the necessary sensors on my engione and everything is within manufacturer tolerances so we're good to go.

I shall, of course, keep you all posted.

its for sale due to other reasons. ie, cant get 2 rotties in it.

but its a merc E300 TD, avantgarde, auto.

this car can reach(and i have done it) 145mph, (confirmed on the sat nav.)

does not take long to get there either.

now i call that a good reason to buy a diesel. and you would never know its diesel when you drive it.

LPG, good stuff, but losing half ya boot is not good. and even with an 80 litre tank, if you are doing alot of miles, you will be filling it every day...

but does save a fortune of you can live with boot loss and constant filling it up... performance loss on a 2.5 bmw with lpg was not really noticeable after pull away...
better getting one already converted, as not alot difference in price to a non converted one... well, from what i can see anyway..

thats my 2 pennys woth lol....