Engine 850: B5234T/2.3/20v/T5: THE definitive word on LPG for T5's....

[classicswede]

If you want the conversion done by a volvo expert then give Mike_Brace a shout 014507 832 290

If you would like a local installer to do the work the try FES autogas 0845 230 1819 they should be able to help you out. There are a couple of comapnys in the essex area who I would strongly recomend you keep well clear of. I shant publicly name them but if you would like to PM me I will happily tell you who they are.

[Trevor Simpson]

I have been following this thread closely .
I have a 1997- 2.5-10 valve on lpg and have covered 52 k without any real problems since tuning system properly ,would definately do it to my next volvo!!
I dont think that there is an issue with valve recession otherwise it would have happened by now . To make it worth it you have to keep the car for a decent period or cover a high mileage , my conversion saves £500 + per year ,cost £1150 five years ago ,laughing all the way to the bank !
Regards Trevor Simpson.

[Muscas]

PM on its way!

Patrick

Originally Posted by classicswede

If you want the conversion done by a volvo expert then give Mike_Brace a shout 014507 832 290

If you would like a local installer to do the work the try FES autogas 0845 230 1819 they should be able to help you out. There are a couple of comapnys in the essex area who I would strongly recomend you keep well clear of. I shant publicly name them but if you would like to PM me I will happily tell you who they are.

[stoatsngroats]

Originally Posted by Trevor Simpson

I have been following this thread closely .
I have a 1997- 2.5-10 valve on lpg and have covered 52 k without any real problems since tuning system properly ,would definately do it to my next volvo!!
I dont think that there is an issue with valve recession otherwise it would have happened by now . To make it worth it you have to keep the car for a decent period or cover a high mileage , my conversion saves £500 + per year ,cost £1150 five years ago ,laughing all the way to the bank !
Regards Trevor Simpson.

Hi Trevor,
I've got the same engine as you, and wonder if you could help with my decision whether to convert to an LPG system?

Is yours auto, and have you had any problems with the G'box?

What fuel economy do you get around town?

What are the additional manitanence cost for the LPG system?

Are you near Sussex, i'd love to look and try!

many thanks,


Sng

[Mono]

Hi all

just been reading this with great interest. Been talking a lot recently about lpg systems and have worked out that just on my commute to/from work I would save over £1k per year therefore I'm on the search for a T5 that's already converted.

Question is, is there anything I should look out for regarding the lpg system over and above a normal inspection when viewing a used car?

Cheers

[chapelhill]

If you have converted yours can you give some real world consumption achieved, ie how many miles and how much fuel from tank up to tank up on lpg and what you would have got for a similar tankful with petrol.

My previous experience was an BMW Alpina 3.5L with single point injection and lambda feedback control. I used to get 26mpg on petrol and 19mpg on lpg.
This is a 15% loss for less calorific value, (100% propane which is what I believe the UK uses, but europe uses Propane Butane mix whih is only 10% less than petrol.) which leaves about 20% for other losses probably due to petrol ignition timing and maybe not being able to run as weak as petrol. (AFAIK Gas is fully mixed whereas petrol vapour will have pockets of richer mixture to start the ignition process off.)
I have been hoping that the turbo might have better ignition curve for lpg!

I want to have my cake and eat it, but is that possible!
The green argument also starts to get lost if additional 20% of fuel is wasted for unsuitability of application. Still, I am really tempted to go for it again!
Thanks in anticipation.
Chapelhill.

[chapelhill]

http://wps.com/LPG/WVU-review.html

this suggests that litre to litre calorific content is 28% down with lpg which equates losely to my 27mpg on petrol and 19mpg on lpg for a 3.5L BMW I have heard reports of T5 getting about 21 mpg on lpg which would predict about 29mpg on petrol for the same drive. this report also shows lpg in UK as 100% propane and also lists that for other countries.

Lots of other useful information on there, I just hope it is correct. I will recheck the calorfic content by doing my own calculations!
Chapelhill

[GavinC]

Interesting link, chapelhill.

I run a singlepoint Tartarini LPG system on a Volvo 960 3.0L and get 19mpg/lpg/motorway at 80mph. (I believe that modern multipoint systems will most likely better that.) I run it 99% of the time on lpg and so have no idea of its petrol consumption though I believe that it'd be 24/25mpg on a 960 tuned specifically for petrol. I manually override the system and always start it on lpg - regularly run it on petrol but only when the car is hot and for just a short distance to keep the petrol system 'live.' Car was converted at 80,000 by the previous owner - now at 176,000 miles and the engine is sweet. When I fill up I am so pleased I am not filling up with petrol.

Power loss...don't know. Must be less but that doesn't concern me as it is more than adequate. If I had a T5 power might, of course, be a priority. BTW if I were to install lpg on a saloon T5, I would avoid the cylindrical tank which is usually mounted in the boot above the axle and go with largest possible capacity donut tank in the spare wheel well (modify the well to expand its capacity?)... or explore some other solution. It'd be great to somehow replace the petrol tank and use the space for an lpg tank - albeit a small petrol tank somewhere would be desirable/necessary. Whichever way, it must be better to have the lpg tank mounted low so as its loaded mass does not spoil the car's handling. However people like classicswede and Mike Brace would have much more experience than myself as to what is and is not posssible with every aspect of lpg conversions. What's true and what is not quite true etc...They might disagree with some of the points I have made above, too.

The calorific issue is interesting, though I always knew there is a difference. I read past the '28%' bit in the link you gave us, chapelhill, to see "Test results show 6% less power with propane than with gasoline." And "Propane use consumes approx 5% more fuel for equivalent performance." (100% propane being the UK lpg mix.)

[classicswede]

The calorific value is lower but the octane rating is much higher. On the traditional mixer type systems a loss of MPG or upto 20% would be exeptable. The Modern sequential systems such as the Dream and Piro would only give about a 5% loss in MPG. When you consider that LPG is less than half the price of petrol when you allow for the reduced MPG you should still expect to save 50% on your fuel bill.

As to replacing the petrol tank with a LPG on a 850 s/v70 is not a practical solution. You would not get much of a gas tank in at all. The 77 ltr tank in the spare wheel well is the best bet.

[Muscas]

Assuming I had an LPG system installed:

Am I correct in assuming, that if I wanted performance I would simply select petrol and if I wanted economy I would select LPG, and normally the system would be defaulted to LPG.

What about the injectors? At the moment I have high flow 600cc injectors, how is the gas injected into the cylinder?

Many thanks in advance for any advise.

Patrick