So from those pictures ^ it looks like that car is set up to run on its regular carbs with fuel and the propane is piped in under the carbs? Is that correct?
So from those pictures ^ it looks like that car is set up to run on its regular carbs with fuel and the propane is piped in under the carbs? Is that correct?
Propane is piped in in this case from the underside of the air-filter-base, so enters from top of the carburator/before the throttle-blades, just like normal air/fuel would.
Yes, you could still run it on fuel instead of propane, gives you both a back-up system to keep your car running if the other system fails or you ran empty of propane and enlarges your travel-range.
On old, carburated cars you could often even start on propane.
Instead on injected cars - to best of my knowledge - they need to start on fuel and warm up a little bit first. They then switch automatically controlled to propane (after about 1 to 3mls of driving, the colder the weather, the longer).
This is how my car ('75 imp 440) is setup, which I think is pretty typical for these cars around here:
Please ignore the mess in the trunk
Behind the rear seat is mounted a 80 liter tank which I think is around 22 gallons? Still leaves plenty of room in my case.
Next to the fuel filler cap I have the lpg fill point, you screw in an attachment that allows for the nozzle to clip onto.
This is my evaporator, it is hooked up to the coolant flow from the heater core to prevent it from freezing up when lpg transitions from liquid to gas. It is an OMVL unit which is Italian I think. In the bottom picture you can see the two set screws in the hoses leading to carb. Those are power valves and have to do with wot.
This is mounted in the air cleaner housing and is where gas is mixed with air. Beneath it is just the regular thermoquad that came with the engine.
On the lower part of the dash I have a three way toggle switch for gasoline-neither-lpg. I have an electric fuel pump so it just cuts the power but it can be done with a mechanical fuel pump. I used to have that and then you need an electric inline valve of some sort.
And no, 22 gallons isn't much compared to the regular fuel tank but you have to realise that the Netherlands is a small country, only about 125 miles wide and 190 miles long. Also lpg is widely available so this is plenty for me.