I have a Feb 2001 reg. Range Rover V8 Vogue; it's fitted with a Nicholson-McLaren sgi lpg system which is worse than useless, and has never worked in the 6+ years that I have owned the car.
Even THEY say it's useless, and should never have been fitted! At least 2 of the 8 injectors are not functioning properly, as well as other parts of the system.
Clearly, to replace the necessary parts of the existing system is likely to cost as least as much as a new front end.
So, with lpg at 49.9p/litre at Morrison's of Wisbech, and petrol at 105.6p/litre, lpg is now less than half the price of petrol, and I'm again tempted to replace the existing sgi system.
I already have a 95 litre doughnut lpg tank and clearly that won't need to be replaced, nor presumably will the services leading from that tank to the engine bay.
I need to know several things, and hope that I may find the answers on this site:

1 - what is the likely cost of replacing the "front end" of my existing system with a quality, reliable lpg system?
2 - what system would anyone recommend? I'm told that Prins is the best, but BRC is perhaps the most 'popular.'
3 - who would be the best person/organisation to fit a good system [I live in Wisbech], but Prins I believe operate out of Wolverhampton!

I know of no reliable, reputable lpg installer in the Wisbech area, and the one known installer has a reputation for perhaps the worst service and technical ability of any that I've ever heard of.

Any advice from knowledgeable people is most welcome, as is any recommendation of a top quality installer.

Thank you for taking the trouble to read this.

Zavoli multi-point is what we have on two D2 V8's that we and our son run, very reliable, especially with the later Pan injectors.

Can't help with a recommendation in your area, mine was done by a guy in Kent who still supports it, 10 years on, and my son's V8 we did ourselves with stuff supplied by Tinley Tech and our guy.

As much as anything else, the parts need to be good quality, any one item below par will screw it up.

The 'standard' LPG ECU is made by one company in Italy and rebadged for the various companies, but the actual installation work is pretty much nuts and bolts and a 'lot' of wiring for the injector drive change-over.

There should be a list of approved suppliers on the LPGUK website:

http://www.drivelpg.co.uk/advice-and-information/code-of-conduct/

Look on that page on the left hand lower edge for the search box.

Zavoli kit:

http://www.ebay.co.uk/itm/161235379416

Peter

The problem as I see it is around half of LPG installers are cowboys. Although I'm not a fan personally, if they are competitive and if they now have LPGA certification or whatever your insurer recognises, go to RPI engineering near Norwich. They do build good engines in a shed there, with parts bought in and not as hermetic or equipped as their webpages suggest, and they know how they work and how LPG interfaces with your efi.