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Discussion Starter · #1 ·
What with U/L at ?1.20 plus and LPG being 0.55 to 0.61 per Ltr

Can we have a section on my MX5 LPG conversions

Pros and Cons

Hints and tips

and for those of you who have already taken the plunge to tells us their stories
 

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Discussion Starter · #3 ·
I`ve got three lpg cars at the moment, far better than diesel imo, Did you do the conversion yourself.
No, I have just booked my car, with PROFESS AUTOGAS

I am having a Fully Sequential Multipoint LPG Injection AC STAG 300 PREMIUM Systems with a 40Ltr donut tank fitted.
 

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Nice, i have a stag 300 on a vauxhall zafria, i found it very good, i also have a stag 400 kit which i hope to fit on my kangoo, if you car returns 30 to the gallon, on lpg it will return 26-27 on lpg, so every ?10 you spend you save ?7.0 so not quite half as cheap as petrol but a big saving all the same.
 

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I have run LPG cars for yrs - great idea IMO.

But I've never paid for a conversion, I bought them all done.

Problem with the 5 is it reduces the already very limited boot space and the weight distribution must suffer too.
 

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I got a quote for the ML 500 of ?1400 for a good quality lpg kit fitted.It doesn't cover many miles so i'm not sure if it would be worth it.The ML averages 19mpg on short runs.
So on lpg it would manage 15-16mpg. almost ?6.00 for petrol ?3-12p for lpg, so every gallon would save you about ?3.00 but taking into account the slightly poorer economy you would save ?2.75, it would take quite a long time to get your money back.
 

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Discussion Starter · #10 ·

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Don't shoot me but I can't help wondering??

For some people would it make sense to run something like a megasquirt with a more economical map than than the standard system on the 5 to reduce fuel consumption? We all know the 5 was not exactly designed with fuel economy in mind. Perhaps for some people this cheaper option might be better.
 

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I drove past a garage yesterday where LPG was 70p - I know its all relative as petrol was 119.9 but it didnt sound so cheap suddenly.

Better to make hydrogen in yourt garage and top up your tank.
 

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Discussion Starter · #13 ·
For those of you who are running on LPG, how much U/L do you keep in the fuel tank?

Do you run light to save weight, or do you keep it full to avoide fuel pump corrosion
 

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No more than a tenner, don`t forget the car will always start up on petrol, in winter that is to protect the rubber diaphragm in the vaporiser, you need a bit of heat to turn the liquid lpg into its gas state for the engine to use.
 

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Discussion Starter · #15 ·
No more than a tenner, don`t forget the car will always start up on petrol, in winter that is to protect the rubber diaphragm in the vaporiser, you need a bit of heat to turn the liquid lpg into its gas state for the engine to use.
Thanks for the reply

Don't you get any corrosion problems, what with the way petrol degrade over time?

The fuel lift pump is still going even when you are running on gas!

A half empty tank would rust quicker than a tank that is full, but the fuel would go off before it is used on a full tank

So I would think that it is a balacing act between saving excess weight / fuel economy and protecting the fuel lift pump
 

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No more than a tenner, don`t forget the car will always start up on petrol, in winter that is to protect the rubber diaphragm in the vaporiser, you need a bit of heat to turn the liquid lpg into its gas state for the engine to use.
Thanks for the reply

Don't you get any corrosion problems, what with the way petrol degrade over time?

The fuel lift pump is still going even when you are running on gas!

A half empty tank would rust quicker than a tank that is full, but the fuel would go off before it is used on a full tank

So I would think that it is a balacing act between saving excess weight / fuel economy and protecting the fuel lift pump
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Not at all, ?10 will last between one and two months, depending on how much stop start you do,petrol vapour is always present in the tank and fuel will splosh around anyway, so all is protected, try not to over think this if you can.
 

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Not quite the same thing but we run a BMW 745 V8 with an LPG conversion. Works brilliantly and paid for itself very quickly - but my wife covers 35-40k per year. The BMW averages 26-ish mpg (nearly all motorway stuff) so running it is quite cheap. However the point I wanted to make is that LPG needs a fair old bit of room for expansion so, for example, we have an 80 litre donut tank but we are rarely ever able to get more than 55 litres into it and this seriously affects your range. It means that on a longish journey, you often have to stop to re-fuel a lot more often than if you ran on petrol.
If we did this again, I'd definetly opt for the biggest tank I could.
 

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Not quite the same thing but we run a BMW 745 V8 with an LPG conversion. Works brilliantly and paid for itself very quickly - but my wife covers 35-40k per year. The BMW averages 26-ish mpg (nearly all motorway stuff) so running it is quite cheap. However the point I wanted to make is that LPG needs a fair old bit of room for expansion so, for example, we have an 80 litre donut tank but we are rarely ever able to get more than 55 litres into it and this seriously affects your range. It means that on a longish journey, you often have to stop to re-fuel a lot more often than if you ran on petrol.
If we did this again, I'd definetly opt for the biggest tank I could.
Ah you have a problem with you tank, probably float height, i have a 65 litre donut that takes 57-58 litres, 90 litre torpedo tank that takes 81-82 litres and a 60 liter torpedo tank that takes 51-52 litres, hope that helps.
 

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Discussion Starter · #20 ·
Well i have had the LPG completed by Andrew of Profess Auto gas.

Very pleased with results,

Andrew listed to what I wanted and did exactly what I asked for.

My car drives no different that before. Andrew manged to shoe horn a 46 Ltr tank into the boot, which should give me 38 litres of usable gas.

I am hoping for a range of 200 miles











 
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