S1rst

Is there a reason why you dont see many 'performace cars' with LPG conversions? Is it maybe because of reliability issues, or not being able to get them running correctly maybe?

Im thinking along the lines of scoobies, evo's, M3's etc. There must be an easy explanation for this as i dont think ive ever seen an LPG scooby, evo or M3.

botters

iTrader: (2)

lpg in non performance cars tends to cause accelerated valve train damaged in my experience with it seen a few with burnt valves usually causing the valve heads to drop off or valve seats to come loose wrecking the engine
this would probably happen even quicker in a performance engine plus im not sure the lpg would make the same power as petrol

Joshy

someone had a ford transit connect with a FRS engine and lpg conversion...

would make 300 brake on lpg as well if i remember??

vinnyvangough

My dad has a 98 Jaguar XK8 with LPG conversion and there is no difference in performance at all.

jamie's

i had a 3 litre 24v shogun with lpg,
it makes no differance to power at all on lpg,
i must have been asked this 100 times, old wives tail i think,
not sure about performance stuff but dont make any differance on average cars with gas

R4N SS

iTrader: (6)

im sure there was a saph cossie in the uk somewhere which was converted to lpg - cant remember who or where tho

Tank Mike

that was moi

The main problem using it in a perfomance engine is.....

Petrol is used quite a lot in engine cooling, Fuel on onver run ect

As lpg is a gas its not as good at the cooling side of things!

Although if you like popsand bangs on overrun,

LPG pops and bangs on overrun are just truely epic

alistairolsen

I suspect because in general LPG is the preserve of the mileage eaters and if youre going to blow 2k on an lpg conversion you buy an economical car to start with.....

JonnyBravo

I've converted everything from a 1 litre Corsa to a 600hp Hummer.

Care needs to be taken on whatever engine you fit it to, wether its worth doing depends on how many miles you do in your car a year.

tabetha

There are 500bhp+ cossie running lpg in Holland, without ANY valve problems, autoflash 2000 is used to combat this.
There are performance race cars that have used LPG, the result was they were BANNED as that gave them a very marked improvement over the petrol cars, some cars can pick up huge amounts when set up on lpg, the main thing being the ignition for best effect needs advancing a lot, I had a wolf n spark advance unit on the one fitted to my xr4i, the result was around 18mpg on petrol, 22mpg on gas, this I put down to the dreadful siamese ports in the head, but a rolling road confirmed the feel, I picked up around 45lbft from memory, it started on gas perfect hot or cold, I'm talking -10C start up was perfect, once I had rejigged the water pipes to have full flow instead of being "t"d into the heater pipes, otherwise the vapouriser turned to a block of ice!!
Plugs last so much better, the oil stays so much cleaner, I was doing 12,000 between oil changes and the colour of the oil was not much different to new, emissions dropped dramatically, engine ran better, so so much smoother, I used a tatarini tech 97 unit on this with a 150 Litre tank!!
tabetha

vaughant

iTrader: (1)

Lots of calibra/cav turbos on LPG.I've got it in the grand Cherokee and there's no difference in performance.you don't get the same mpg,usually a touch worse but at 60p per litre you don't mind,although I did notice it had crept up to 70p last time I looked which is naughty,a far higher percentage increase than petrol.

stuarth

there was a b4 and after power graph way shogun and it was 1 bhp up on gas

3drzetec

im not a 100 % but arnt the AON focus's in the british touring cars running on lpg ????

Chip

iTrader: (3)

That was mikes (tank mike on here) and it was just over 200bhp on the gas but nearer to 300 on petrol.
That was only cause he was still using the 1800 gas kit though and it wasnt man enough to supply more fuel, probably could have got closer if he tried but TBH there is no point really when you think how rarely you need full power, just switch back to petrol when you do.

ZTSI

there was a think in FF i think about the focus touring cars that use it saying, if i remem right, that they was puming the lpg in to the engine as a liquid and not a gas as,they couldnt get the right amount of gas in to get the right power 8 injectors, ill have to dig the mag out if i still have it.

Chip

iTrader: (3)

LPG is high octane, so from that point of view is good for performance, you just need to find yourself a set of nimonic exhaust valves

JonnyBravo

These Focus's
http://www.prinsautogasuk.co.uk/News/Touring.html

I'm quite familiar with the Prins system, IMO its one of the best kits available

CarParts Express

When I had my impreza (gone now) converted to lpg i had a flashlube system fitted to eliminate the worry of valves burning out
http://www.flashlube.com/en/products...saver-kit.html

JonnyBravo

Most japanese vehicles have to run flashlube systems. Prins developed a electric flashlube system just before I left the job.

Some jap models could suffer valve failure within a few thousand miles of being converted, we had a Primera with a missfire in that someone had done which turned out to be valves. We quite simply would not of done the conversion on a car like that as their known to fail.

Chip

iTrader: (3)

Whats actually in the "lubricant" jonny, has its not a lack of lubrication killing valves its EGT's surely?

JonnyBravo

Couldn't answer that mate sorry, it maybe on that link

Chip

iTrader: (3)

No mate, it just refers to it as "Upper Cylinder Lubrication System" everywhere I can see any mention of it at all.

Nothing about how that helps LPG cars not burn out valves!

foreigneRS

my galaxy has a flashlube system on it as well.

Chip

iTrader: (3)

Do you know what is actually in it then or specifically how it works?

foreigneRS

no idea. the father in law had it done. the system basically sucks some of the flashlube in under vacuum and the idea is to somehow 'lubricate' or coat the valve seats to protect them. seems odd to me, but as i've got it i leave it on. i'll try and remember to have a look at the bottle and see what it says.

Rick

it is probably to stop microwelding of the exhaust valve and seat.

Rick.

Graham S1

That used to be the case with the old "mixer ring" systems that fed in through the inlet manifold, but not so much these days with the sequential kits used. Think these have less chance of backfire too.

RS Grant

iTrader: (1)

What sort of cost is involved in converting a B6/B7 Audi S4 with the 4.2 V8 engine mate?? One of my friends is looking at these cars and he is after the Avant because he needs the space for transporting dogs etc... what sort of size of tank could usually be dropped into the spare wheel space in the boot floor??


Cheers,
Grant

lawnsy

iTrader: (1)

there a place near me doing 8 cyl cars with multipoint for £1250

stevieturbo

I was at a trackday with a friend, late October at Bedford Aerodrome, where Palmersport is based.

All of the Palmersport cars appeared to be LPG. From fancy single seater race cars, to the M3's

Which makes perfect sense really. It is a good fuel. And why the fuck should they pay extortionate taxes on normal fuel, for vehicles that will never see a public road.

Biggest issue with LPG, is that most installers are simply installers who know fuck all about engines or tuning.
Second issue is, gas supply. I think a single condensor is only rated to around 300bhp ? So any more than that, and you start to need a pair or more to get the required volume of gas to the engine. Then injector sizes, etc etc. Plumbing can start to get very very messy, if there is room at all.