I have tried google and many of the websites for companies which convert petrol cars to LPG, but I cannot find a definitive list of makes and models which can be converted.
can anyone point me in the direction of one of these lists ? or even better tell me if it is possible to convert a 1970 VW T2 Campervan.
I don’t know much about conversions, but I think it would be a problem in a van, as you have no place to mount the tank outside the pass. compartment. I’m pretty sure it would be a bad idea, if not illegal to have it inside the van.
Its quite possible to convert vehicles of that vintage, I’ve an old magazine rattling around somewhere that covered the subject. If I find it at the weekend I’ll let you know what it says inside.
The only problem I can think of was that cars had space in the boot or spare wheel well for a tank, I can’t see it working if you’re trying to replace the nose mounted spare wheel 
The fact that it is air cooled may be a problem. Cars use LP faster than it can evaporate from an unheated tank, so the tank would frost up and lose pressure. To avoid this, liquid is drawn from the tank rather than vapor. (as is done for BBQ grills and suchlike) The liquid is then converted to vapor in a device known, appropriately, as a vaporizer. The vaporizers typically use engine coolant as a heat source.
I can imagine a device with lots of fins in the VW air cooling stream that might work similarly, but it is not an off-the-shelf item like the liquid heated version.
My Chevy van runs on propane, it has two 18 gallon tanks. One is mounted on the driver’s side, with the fill valve located under the edge of the body, looks pretty much like the standard setup for an old RV. The front tank is mounted under the body, inside the frame rails, with its long axis parallel to the length of the vehicle. The second tank is mounted in back, where the gas tank would normally be and the long axis is perpendicular to the long axis of the body. The fill valve is behind the normal fueling door.
One criteria that’s very important in deciding whether to go with an LPG conversion is whether or not the vehicle has case hardened valves. Fords will go through valves every 100K miles–they don’t like the chill of the fuel. Chevies do well on propane because they do have case hardened valves–my van has for sure 250K miles on it without a rebuild and might have as many as 350K and it has good compression in all cylinders with less than 18% difference between the highest and lowest cylinders. It will probably go on like this until I’m forced to beat it to death with a stick!
I’ve seen VWs converted to propane before–not sure how they get around the fuel warming issue but there must be some kit that’s specific to air cooled vehicles.
I’m sure one can use hot motor oil.
Thanks for you replies.
I will speak to some garages that do conversions, and hope for a realistic quote.