i currently have a 1981 F150 2wd named Clyde. Clyde is my daily driver, a truck that sees roughly 300-500 miles a week, and im on a quest for cheaper driving. I am very seriously considering a duel fuel propane/gasoline setup, where i would drive primarily on propane, but have gasoline as a last ditch effort.
So, please, as an uneducated fool, can someone point me in the right direction??
You can use an Impco CA300 mixer with a Model E converter. That will be a good set up for you. I would also recommend a 12 volt LPG Filter lock off not a vacumn unit and you will need a 12 volt gasoline lock off. Be aware converting older high mileage motors can lead to valve/engine failure. Once you get it done you can bump your intial timing 1 or 2 degrees BUT NOT ANY MORE than that for increase power on LP. Start with your local LP Gas suppliers for the equipment. Your biggest expense will be if you have to buy a new tank.
Propane is about 30% less efficient than gasoline. So mileage and power will be down. But engine wear is reduced and with the higher octane level of LPG (around 110) next to no engine knock. Long as your area/state does not have smog checks every so often then its legal.
The big advantage of propane is it self-adjusting for elevation. So you could switch over to propane while going up and then adjust your carb(s) when your up there. Another thing is, it can be at any angle is still combust. Which is why a good number of people use them for off-road/rock crawlers. Where gasoline will stall out, propane will keep going.
You'd probably want a 100lb tank bolted to the bed of the truck or run 2 forklift 40lb tanks and have them clamped down. Kits are not entirely cheap (about $1200+) and you won't really see a huge cost benefit (less mpg but fuel is pretty cheap).
Just recently with low fuel costs, had to fill up a grille propane can (20lb) and it cost $17 to fill it up! So its around $0.90 per pound right now.
thanks for the info man. my old 1981 F150, Clyde, has been passed on to a new owner, but my ideas of running propane are still in my sights. i may run full on propane (nogasoline) on my little autocross toy im screwing together, so your info will go to good use.
Our farm truck is a 5.4 that has a dual fuel setup. It works very well. We buy propane by the tanker load so our current price is $0.70/ gallon. The price easily makes up for any loss in mileage. The actual mileage loss is about 10%. And I'd recommend at least a 40 gallon tank in the truck because they can only be filled to 80% to allow for expansion.