LPG Discussion Forum

Hi,
for a fuel return line to work, you need a restrictor in it. Its probably best to put a T piece in your pressurised fuel line. put the relief valve on one let of the T make up a plug to fit in the inlet side of your relief valve, and drill a small hole in it. (you need the pump to be able to ...

These figures are all very well, but they must be making strange assumptions about the constituents of the fuels.

The only ones with really well defined fixed constituents are Methanol and ethanol.

LPG is a variable mix of propane and butane

Petrol is typically a mixture of the various octanes ...

I think you will find that adding butane improves performance somewhat. You may find that BP are using pure propane, and others are using a blend with more or less butane in it. On a kg/kg basis propane has a very slightly higher calorific value, but on a gas volumes basis the butane is about 30 ...

Theory only, but if you compress the input charge to say 14.7psi boost, and then cool it back down to ambient, you will generate 0.42kW per litre (engine size) per 1000 RPM. The compression process is not 100 % efficient so it generates more heat, but you will not be looking to take too much heat ...

a different option may be to go for faster lpg injectors? such as the magic jet ones?

butane melts at -140C, so that wont be a problem. It does boil at -1 C, which might make things tricky if LPG was pure butane. but it isnt it has propane as well, which boils at -44C

Hi all,
right so in fact its the positive supply to the multivalve that is not working. Got a get me home fix by running a new positive lead from the solenoid to a switched positive, and I guess this weekend I will be playing find the break in a cable. Best guess is it will be at one or other of ...

Hi,
thanks for the tip.

as should have been obvious, I know how to do the electrical checks. What I needed to know, still do is what is the recommended safe way to check if the valve part of a solenoid valve is working?

If there isn't a safe way, then it looks like having to replace both valves ...

I can't switch to lpg. :( Ok I can work the switches but I am getting very low LPG pressure.
Took the vapour filter off and got no hiss or smell, so looks like the gauge is reading correctly. My system is a stag 300 on a 3l s-type jaguar. Large doughnut tank in the spare wheel well, with a solenoid ...

Probably a bit late for my input, but:

go for a petrol bypass.
You have to take the inlet manifold off to drill and tap it safely; this means you have to take off the wipers, scuttle and brace bar, and gives you a lot more room to plumb in the vapouriser etc.
While its off you can change the plugs ...

Hi All,
if you want to be able to reliably use petrol and lpg, on the S type, then the best way is to put a bypass in the petrol line. Put in a t piece, with the straight through part going to the injectors, from the third leg of the T put in a restrictor then solenoid valve and return line, feeding ...

Hi, if you check on the mazda rotary forums, you will see that this sort of conversion does get done fairly often, more so with RX-7s than RX-8s, where mpg was usually in the region of 18-20, and after market CPUs for controlling boost as well as ignition timing and injection are the norm.
The ...

Hi Joanne,
water is one of three main compounds from burning LPG or petrol, the other two being carbon dioxide and carbon monoxide. If you run rich, then you get more carbon monoxide, and in theory more power, but worse fuel economy. If you run lean you get less carbon monoxide, but your engine will ...

for correct operation, you should also make sure the box is ticked (or not as the case may be) for the software. ie petrol injectors driven by + If it isnt tick the box marked no! weird logic for the Stag device.

Yes, Andy was pretty helpful, and I would have used them to rectify the faults, but the distance involved was not worth taking to them.
Value for money: certainly.
Time taken to do the job: 1 day (OK a very long day, about 15 hours)
Would I go to them again? No, but only because of the distance ...

Professautogas did my s-type. THe attraction was that they could do it in one day, on a saturday.

At that time (and possibly still today) they did it without removing the inlet manifold. If I had known it would not be coming off they would not have had my car. They claim never to have had a ...

My 2p worth back here.

As far as I am aware COP11 is not a Legal requirement, its a standard put out by the LPGA.
If I am wrong, could someone point me to the UK legislation where it has become a legal requirement?
Particularly worrying for me would be the fact that the line from my LPG tank ...

many thanks for the info, although Doncaster is a bit too far out of my way.

Hi, where in Ipswich is the filling station at 72.9? I have to go to Ipswich on Thursday, it would be nice to get a low price fillup.

cheers

Hi,
If you drive reasonably you should get more than 260 miles from a 60l tank.

But, depending on age, you may well find yourself with only 80% of the power. (greater power loss from more modern engines, compared with older ones) This is not usually a problem with a large engined car, with the ...