LPG: mileage and underslung tanks...?

Hi

I'm looking at buying a Disco 3.9 v8 with an LPG conversion, to go touring France in. Does anyone have (or know about) an LPG conversion, to the extent that they can answer the following:

What sort of mileage can I expect from a Disco 3.9 v8 running on LPG (figures for petrol MPG would also be helpful for comparison)?

How do underslung tanks affect the ground clearance? To what degree do they limit off-road ability? What's the risk of damage?

Thanks for your help.

Kevski said:

Hi

I'm looking at buying a Disco 3.9 v8 with an LPG conversion, to go touring France in. Does anyone have (or know about) an LPG conversion, to the extent that they can answer the following:

What sort of mileage can I expect from a Disco 3.9 v8 running on LPG (figures for petrol MPG would also be helpful for comparison)?

How do underslung tanks affect the ground clearance? To what degree do they limit off-road ability? What's the risk of damage?

Thanks for your help.

Click to expand...

I don't have one, but from everything I've read, fuel consumption along the following lines would be a decent guide:

Petrol average for touring purposes 16-18 mpg
LPG - depends whether single or multi-point - 13-16 mpg

O dear "thebiglad" has beaten me to it, the figure he gives is right although I read of an owner getting only 11mpg on petrol.
I had 13mpg about town for a period of 2 x 3 miles a day so I don't do that any more, and up to 21 on a 200 mile non stop run thats with petrol. My average is 18 or so, I don't do a high mileage so haven't got LPG.

With your tanks, at first it was the tanks in the boot and then came the underslungand and yes underslung tank/s do restrict the ground clearance the amount understandably must depend on the size.
The thing now is, because there are more gas filling points around now, is to remove the petrol tank and have a gas tank fitted with a smaller petrol tank both custom made to fill the space once occupied by the petrol tank. See the May 08 issue of LRO where thay have converted a staff disco, the installation looks very neat.

Regards

ive got 1, a 1996, it has twin underslung tanks, it costs about £27 to fill and i do about 175 miles for that and thats in rural wales, i get more if i do motorway miles, i love it but the bugger keeps breaking (i used to have a 1993 BMW 325i which never broke) 1st the ABS, then the shocks, now the water pump. sometimes i wonder why i bother but i bloody love it.

I have a Range Rover classic, 3.9 EFI running on gas, it costs £35 ish to fill and will do 225 miles, average cost per mile is 16p (50p/l) I'm getting 14 miles per gallon on mainly motorway miles. I have never ran it on petrol though.

I have the tank in the boot, the only problem it caused was fitting speakers but a pair of enclosures sorted that, might restrict load space if your touring though.

I do about 700 miles a week so I have plenty of info on fuel consumption!!!

the U straps on the underslung tanks are prone to being torn off if you plan on off roading it alot.

A couple of guys in our club have gas conversions and both of them opted for boot tanks, removing the underslung ones('cos the mounts kept ripping off). but then these cars are their greenlane/off road toys!

Well, we went and bought a "pretty blue one" (oh dear, bless 'er!), otherwise known as an '03 v8 4.0 auto (petrol), which is now booked in for a split-tank LPG conversion. Apparently, there should be 70 or so litres of LPG available once complete, as well as another 20 for petrol (manual says original petrol tank is 95ltrs).

Thanks for the advice/info everyone.