Another idea from PPC! LPG + Turbo

[GrindCulture]

Anyone else seen then R5 turbo in PPC this month running on LPG? This sounds like the perfect way to turbo M42s (you knew that was coming didn't you?) or early high comp M20s. High compression engine, 110RON, with proper mapping you could safely run more boost than on petrol, therefore getting more power without sacrificing the off boost response, and better fuel consumption

Discuss

[daimlerman]

Yes,this answered most questions.But no indication of how cold starts were catered for.My understanding of LPG instals is that petrol is stil needed untill the cooling system is up to temp and able to pre-heat the LPG. When I see a satisfactory answer to this,we are in business!!

[gareth]

mine will start on LPG from cold with no problems... when it's working that is!!!!
i ran for a few days with no petrol pump and was glad it woud do this

[GrindCulture]

It's putting more ideas into my head to waste money I haven't got on a car with the wrong number of cylinders.

[Brianmoooore]

There's no problem starting a car on LPG at any temperature likely to be found in the UK, as long as you don't load the engine heavily for about a mile. The LPG only needs to be heated above around -40C, IIRC.
One problem in the UK, is that we don't have a proper formulation for autogas, and it's content (and RON) can vary considerably. With a bad batch, it could be down to as low as around 100 RON.

[Chuntington101]

There's no problem starting a car on LPG at any temperature likely to be found in the UK, as long as you don't load the engine heavily for about a mile. The LPG only needs to be heated above around -40C, IIRC.
One problem in the UK, is that we don't have a proper formulation for autogas, and it's content (and RON) can vary considerably. With a bad batch, it could be down to as low as around 100 RON.

yes but even if we only assume 100ron and tuine accordingly it still going to be a fair bit better than with petrol...

also what are the cooling effects of the gas??

has anyone fitted indavidual injectors on gas setups??

Chris.

[Brianmoooore]

The cooling effects of gas are much greater than that of petrol BUT any practical DIY LPG system is a vapour injection or venturi based type, where all the cooing takes place in the vapouriser, before the gas gets any where near the engine, so the charge cooling effect is a big fat zero!
Nothing unusual about individual injectors on LPG systems, but these are normally vapour injectors.
Many of the problems experienced with using petrol as a fuel arise from the difficulties involved in changing petrol from a liquid to a gas ( or, to be more accurate, into small liquid particles) and keeping it so.
LPG readily turns into a genuine gas, and has no tendency whatsoever to revert to a liquid, so the advantages of injection over a carburettor are nowhere near as great as with petrol.

[casper8r]

Ah, but the original post mentions a turbo setup, correct me if I'm wrong (which I very often am) but you can't use a venturi based system on a turbo engine, non?

[Brianmoooore]

You can if you feed the mixture through the turbo, OR you use a vapouriser which has a connector to the 'atmospheric' side of its diaphragm (plenty have), and connect a tube to the downwind side of the turbo, so that the vapouriser's reference pressure is the boost pressure.
Only problem is that you need to 'pre load' any pressure relief valves you have for blowback protection.
One of the set ups I have came off a turbocharged Volvo.

[cplagz]

Check out Pete's turbo E30 build.... he's running LPG
http://members.iinet.net.au/%7Eu9013943/bmw3.htm

[Jon_Bmw]

Check out Pete's turbo E30 build.... he's running LPG
http://members.iinet.net.au/%7Eu9013943/bmw3.htm

Thats fairly Heroic! He's brave with those spacers as well!

[GrindCulture]

Jon how much did your LPG setup set you back if you don't mind me asking?

[Jon_Bmw]

Total cost £220 Sir. Should pay for itself with a few more tankfuls!

[handpaper]

You can if you feed the mixture through the turbo, OR you use a vapouriser which has a connector to the 'atmospheric' side of its diaphragm (plenty have), and connect a tube to the downwind side of the turbo, so that the vapouriser's reference pressure is the boost pressure.
Only problem is that you need to 'pre load' any pressure relief valves you have for blowback protection.
One of the set ups I have came off a turbocharged Volvo.

I'm planning something similar for my LPG-only track car - let Motronic do the sparks and AEB the fuel, happy days.
Personally, I'd be much happier using a compensated vaporiser than running mixture through a turbo (and intercooler). The thought of how much damage could be done by just one backfire is.......unsettling

[SCOTT325SE]

Total cost £220 Sir. Should pay for itself with a few more tankfuls!

£220???? HOW!?
explain please Jon!

Drop me a PM if you would be so kind.

[Jon_Bmw]

Pm sent.

Also I reckon it could be done for about £160 with the right bits and a bit of luck.

[GrindCulture]

Worth considering I think then. I'll have to have a read up. You did all the work yourself I gather?.

[SCOTT325SE]

I assume its all second hand stuff we're talking about with ultra-low budget kits we're making up.
Does anyone know how much a kit would be if it was all bought new?

[Brianmoooore]

Does anyone know how much a kit would be if it was all bought new?

Around £600 - £700.
£200 is realistic for second hand parts, plus a few pounds for new pipework.

[Brianmoooore]

Worth considering I think then.

Been telling that to anyone and everyone who will listen for the last ten years. Why anyone who does any kind of mileage would run a car on engine wrecking, expensive petrol is beyond my comprehension!

[Jon_Bmw]

Worth considering I think then.

Been telling that to anyone and everyone who will listen for the last ten years. Why anyone who does any kind of mileage would run a car on engine wrecking, expensive petrol is beyond my comprehension!

Love it.

When and if I do another one, i'd be rather tempted to use a fully sequential setup to try and maximise performance and economy.

[aceraf]

Worth considering I think then.

Been telling that to anyone and everyone who will listen for the last ten years. Why anyone who does any kind of mileage would run a car on engine wrecking, expensive petrol is beyond my comprehension!

I know I for one don't have the expertise or time to carry out a conversion. I also don't know what parts would be required. And there's also the location of the filler point for the LPG, doesn't it involve cutting?

Most places that do LPG conversions quote around £1200+ for a fitted system, and while it does pay for itself, I for one am not willing to pay that, if a system can be fitted for as little as £200. I would like to do it myself, but then you don't have a certificate for it.

Is there anyone on the zone that would carry out a conversion on my touring, and if so how much?

[Brianmoooore]

Expertise: No great levels required to fit a venturi one. Anyone who can change a cambelt or suspension components should have no problem.
Time: The conversion can be done in several easy stages, none of which take the car off the road for more than a couple of hours at a time.
Parts require: That's what the zone is for.
Filler: Can involve cutting if you want it to, otherwise mount the filler on a tow bar or off a bracket bolted to the rear right bumper mount.
Certificate: I don't have one, on principle! No one asks for a certificate when I've been playing around with the petrol fueling system, so why should one be needed for the inherently more safe LPG system?

[aceraf]

Expertise: No great levels required to fit a venturi one. Anyone who can change a cambelt or suspension components should have no problem.

LOL, never done either, but point taken.

Time: The conversion can be done in several easy stages, none of which take the car off the road for more than a couple of hours at a time.
Parts require: That's what the zone is for.

I was thinking more in times of working 9-5 and then having a lack of daylight to be able to work in. I don't have a drive or garage to work in.
Can anyone give links to all the parts whta twill be required, I know you can find 2nd one's alot cheaper, but for people who don't really know what to look out for it'll be easier if link or a list of parts required.

Filler: Can involve cutting if you want it to, otherwise mount the filler on a tow bar or off a bracket bolted to the rear right bumper mount.

I'll be fitting a tech 2 kit so just don't want to be cutting the kit.

Certificate: I don't have one, on principle! No one asks for a certificate when I've been playing around with the petrol fueling system, so why should one be needed for the inherently more safe LPG system?

Don't some insurance companies require one?

[handpaper]

I fitted mine to the car as it stood on the street outside my house. Do things in the right order and the car is never undriveable for more than a few minutes at a time.

Some insurance companies will try to refuse cover without a certificate, but there is no legal basis for this and many can be argued round. Adrian Flux tried it on with my conversion and were told where to get off - result, cover unchanged, premium unchanged, 'amendment fee' waived.

[stonesie]

My conversion was a little more coming in at about £300, half of that was for a brand new leonardo to run it as i wasn't lucky enough to come across a 2nd hand one for sale.

All in all im saveing about 1/3 on running costs, i ran my gas tank dry for the first time in general driving and got 180 miles and it cost me under £20 to fill the tank untill it cut off, for a 320 touring with a 4.27 diff that's not bad and i will soon make the money back

[aceraf]

Very valid points.

I've been thinking about this alot, and would like to go through with a conversion on my touring.

However I feel that it's currently using alot on petrol. I drive only around town and it's constantly stop start traffic and bendy bumpy roads that i have to keep slowing down for. I haven't really worked it out, but I full tank my car whenever i fill up, and usually fill up before the light comes on. I'm on average getting around 200miles to a tank. I must add that does involve quite a bit of foot to the floor driving when i'm in a hurry, and as i say is alot of start, stop driving. When i've fueled up, i've worked out from how much went into the tank that I've got around 11 litres left in the tank when i fuel up again, and usually brim it to the top. The exhaust fumes do smell pretty rich, and I can't find any leaks (checked when it rains to see if there's petrol on the road but nothing!

No water/oil/petrol leaks that i know off.

Is my car running really badly or is it just because of the journeys i'm making? My longest journey is normally about 2miles, and that as i say is stop start.

I had the car looked over by Chris Warburton a little while back, and he adjusted the tappets for me, but nothing's really changed. Car was last serviced around march time.

Would i be better off getting it to run better on petrol before looking into lpg'ing it? I think i'm usually averaging just under 20mpg or probably about 21 or 22 when i don't drive it hard, and try and drive as economical as possible.

A full tank will usually last me between 2-3weeks.

[Gunni]

20mpg is not good at all mate

you should check your O2,

[Jon_Bmw]

Mine managed 270 miles to its tank the other day and I don't think it was totally full. I worked out a rough idea of what LPG I had put in, the miles I had done etc. It worked out as the equivlent of 54.5mpg when taking the fuel price into consideration.

It was doing 28mpg in real terms, but mainly longer journeys. Think a buzzing 318is diff. I'm happy with that I think. It should get a bit better when I tweak it on the laptop.

[Gunni]

I put 37liters in mine and am already at 200miles, it should make about 15-20miles more until it´s at the same spot as before.

First 100miles was M1 going at least 85mph average.
Back again M1 70mph average.

That´s 8.3gallons it seems and that´s 24mpg at the moment with more mileage to come.

[aceraf]

20mpg is not good at all mate

you should check your O2,

How do i do that?

It used to be alot worse (12mpg ), untill i changed a few parts (blue + brown temp sensors, can't remember what else).

[Brianmoooore]

Would i be better off getting it to run better on petrol before looking into lpg'ing it?

Normally I'd advise anyone to get a car running absolutely as new before doing any kind of tuning or modifications, but if the problems with this car are entirely confined to the fueling system, they won't make any difference when running on gas.

[gareth]

mine when either a 2.5 or 3.5 would only ever get around 200 miles to a tank full of petrol as i too only ever do short runs. i've worked it out more accurately recently though... on gas, i'm getting about 17mpg round town and if careful on a looooong journey (to the 'ring) i managed around 33 - 35mpg!!! on petrol i get slightly better mpg (20ish round town)

oh, for the record, it's not adrian flux themselves who dictate the need for a certificate, i'm with them and have equity red star as my underwriter and they didn't need a LPG certificate. they also cover me fully for use on the 'ring so it's worth asking who the underwriter is at quote stage

[aceraf]

mine when either a 2.5 or 3.5 would only ever get around 200 miles to a tank full of petrol as i too only ever do short runs. i've worked it out more accurately recently though... on gas, i'm getting about 17mpg round town and if careful on a looooong journey (to the 'ring) i managed around 33 - 35mpg!!! on petrol i get slightly better mpg (20ish round town)

oh, for the record, it's not adrian flux themselves who dictate the need for a certificate, i'm with them and have equity red star as my underwriter and they didn't need a LPG certificate. they also cover me fully for use on the 'ring so it's worth asking who the underwriter is at quote stage

Not really done a long run in a while, so don't really have anything to compare it to.

Oh, and I also have subs in my car aswell that probably weigh about 30Kg minimum that i'm carting about, and apart from my journey to and from work I've always got atleast 1 other person in the car aswell.

How do I adjust the O2 as someone suggested? The exhaust fumes do smell very rich.

[Gunni]

you replace it,
it´s most likely faulty.
go to Halfords and get a replacement