Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Arpy on 20 July 2007, 20:42:02

Title: lpg conversion
Post by: Arpy on 20 July 2007, 20:42:02
just had my car converted and so far so good but just wanted to know from someone who has converted how does the pump know when to stop putting gas in I have a 59 litre tank and it stops at 45 i know they are supposed to have a certain amount of space what is the %.
Also my car averaged about 27 mpg now its 21 i thought the new lpg systems where more or less the same as petrol??
Title: Re: lpg conversion
Post by: TheBoy on 20 July 2007, 20:50:49
Martin Imber will be able to answer fully.

Howver, tank capacity is about 75% of its stated capacity, and economy is normally a good 10% lower than petrol.
Title: Re: lpg conversion
Post by: Arpy on 20 July 2007, 21:43:14
how do i get touch with martin
Title: Re: lpg conversion
Post by: TheBoy on 20 July 2007, 21:47:01
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how do i get touch with martin
He'll respond soon enough, as will other LPGers I expect.
Title: Re: lpg conversion
Post by: Danny on 20 July 2007, 21:56:09
half price fuel though!!!
Title: Re: lpg conversion
Post by: Craig_R on 20 July 2007, 22:09:07
I have a 65 or 70 litre tank in my car and i can only get 55 litres in it.

Its a safety Thing so the Gas can Expand and pressure and stuff.

There is also a pressure valve on the tank for venting gas for say you fill up at night when its cold the LPG takes up less room and then if you have not used much and its a Hot morning the gas expands and needs to be vented to help not stress the tank under pressure
Title: Re: lpg conversion
Post by: The Cambelt Kid on 21 July 2007, 21:08:00
My 2ltr Omega has an 80L tank and I can squeeze in 65/66 lts of LPG at the pump.  I have just bought another 80ltr tank for my V6 conversion so I guess I’ll fit in about the same.

Power seemed to be down a fraction when I first did the conversion, although having just replaced the cam sensor I have seen a slight improvement!

I managed to get to north Wales and back on £25 of LPG which is a touch under 400 miles!  :)
Title: Re: lpg conversion
Post by: JamesV6CDX on 21 July 2007, 21:10:48
Althought not a Meega, I have a Vauxhall with factory fit SGi gas, savings are immense. I can do 150 miles on £8...
Title: Re: lpg conversion
Post by: Martin_1962 on 21 July 2007, 21:18:07
They have a valve like a toilet cistern - uses the fluid level.

You will get about 10 to 20% worse consumption as there is less energy in a litre of propane than petrol
Title: Re: lpg conversion
Post by: Taxi_Driver on 22 July 2007, 06:40:35
Quote
They have a valve like a toilet cistern - uses the fluid level.

You will get about 10 to 20% worse consumption as there is less energy in a litre of propane than petrol

As Martin says.....its normally 20% less than cylinder size to allow for expansion....pray it breaks and you can over fill it  ;)

I was getting av 20mpg outa my 2.2.....but its gone to 22/23mpg now.....so your about right  :y
Title: Re: lpg conversion
Post by: Arpy on 22 July 2007, 20:34:34
thanks for input interestly yesterday managed to get 49.5 litres compared to day before only 45 .5 so temp is important factor.
just wondering if the brass screw on outside of tank is the pressure valve for tank and if so can you adjust it????
Title: Re: lpg conversion
Post by: Taxi_Driver on 22 July 2007, 20:51:24
Quote
thanks for input interestly yesterday managed to get 49.5 litres compared to day before only 45 .5 so temp is important factor.
just wondering if the brass screw on outside of tank is the pressure valve for tank and if so can you adjust it????

Did you fill up at the same place? Coz some pumps dont actually put in as much as they say.....its not monitored by any authority....if you get my gist  ;)

As Martin says it works on float system for the filling......dont go fiddling with it  :y
Title: Re: lpg conversion
Post by: Arpy on 22 July 2007, 20:59:53
yes it was same pump
is your sytem a new type ie sgi cos from all info i have read new type was supposed to be very close to petrol so if 20% on new type how bad was the old system
Title: Re: lpg conversion
Post by: TheBoy on 22 July 2007, 21:06:37
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yes it was same pump
is your sytem a new type ie sgi cos from all info i have read new type was supposed to be very close to petrol so if 20% on new type how bad was the old system
10 - 20% just because lpg has less energy per litre than petrol.

Mixers not much less uneconomical.
Title: Re: lpg conversion
Post by: Taxi_Driver on 22 July 2007, 21:44:05
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yes it was same pump
is your sytem a new type ie sgi cos from all info i have read new type was supposed to be very close to petrol so if 20% on new type how bad was the old system

Yes mine is sgi.....and as TB says calorific value is lower so you use more...you must notice you have less power on lpg....so probably put your foot down more......like me...so use more lpg  ;)
Title: Re: lpg conversion
Post by: Taxi_Driver on 22 July 2007, 21:50:41
Quote
yes it was same pump
is your sytem a new type ie sgi cos from all info i have read new type was supposed to be very close to petrol so if 20% on new type how bad was the old system

Ok thats a bit odd its that different.....sometimes i can keep forcing mine to run on lpg when its empty....its keeps switching back to petrol pretty quick....and i get 37/38L in the tank....other times i dont bother to keep switching it and ive got 39L in it.....

5L difference is a bit puzzling  :-/ filling up at the same pump.....unless the float switch is a bit sticky  :-/
Title: Re: lpg conversion
Post by: JamesV6CDX on 22 July 2007, 22:07:50
Veccy runs better on Gas than petrol...
Title: Re: lpg conversion
Post by: TheBoy on 22 July 2007, 22:22:53
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Veccy runs better on Gas than petrol...
szomething wrong then.....
Title: Re: lpg conversion
Post by: Martin_1962 on 22 July 2007, 23:25:05
No there isn't mine is as follows

Smoother on gas except at idle, idles smoother on petrol, performance about 2 or 3 % better on petrol
Title: Re: lpg conversion
Post by: TheBoy on 23 July 2007, 08:46:00
Quote
No there isn't mine is as follows

Smoother on gas except at idle, idles smoother on petrol, performance about 2 or 3 % better on petrol
Really? I stand corrected...

Though I was thinking that by 'runs bettter' he was referring to power available and power delivery...
Title: Re: lpg conversion
Post by: Martin_1962 on 23 July 2007, 09:16:42
Quote
Quote
No there isn't mine is as follows

Smoother on gas except at idle, idles smoother on petrol, performance about 2 or 3 % better on petrol
Really? I stand corrected...

Though I was thinking that by 'runs bettter' he was referring to power available and power delivery...
:D :y
Title: Re: lpg conversion
Post by: Rank on 23 July 2007, 15:27:07
Quote
just had my car converted and so far so good but just wanted to know from someone who has converted how does the pump know when to stop putting gas in I have a 59 litre tank and it stops at 45 i know they are supposed to have a certain amount of space what is the %.
Also my car averaged about 27 mpg now its 21 i thought the new lpg systems where more or less the same as petrol??

Hi There

Had my 2.5 V6 converted two years ago. Pump stops automatically when filling. It based on pressure. You will here a slight "clunk" and the rate of fill will slow down. You can keep going until the pressure equalise and it stops altogether but this wears out the filling pump. Amount of fill depends on pressure in garage tank.

Hope this helps