I got about 8.6 miles per US gallon in a F350 crew cab w/460, no load and about 5.5 mpg after I put a huge camper on it; total weight with the camper was 8000 lb.

Propane systems are very simple, there's a tank, a hose, a vacuum operated propane lock, a regulator, and a feed hose which will go to the air cleaner or throttle body.

My 460 is also fuel injected so it has a feed hose that runs to the air cleaner whereas a carbeurated unit will probably run a propane throttle body. My truck was converted before I bought it so I didn't do the conversion but a friend of mine did his own conversion; he's also very mechanically inclined.

There shouldn't be any electrical involved at all unless you are going to run dual fuel and the propane safety lock is vacuum operated so there is no flow if there's no vacuum. Well maybe the fuel guage wire will have to be hooked up. Some systems use a box to trick out the stock computer so you don't get CEL coming on all the time. Doing an install on a carbeurated engine with no ECM would be the easiest.


If you're building an engine to run propane I would go 9.5 - 10 perhaps even 10.5 compression to get the power out of the high octane fuel and you can easily run 15 BTDC timing probably more without any knock.

I've seen a lot of propane trucks at the wrecker, one could easily snag a complete system off one of them and make install it in their own vehicle.
this goes without saying but if you decide to do an install yourself make sure you test all connections with soapy water looking for leaks..

Propane has jumped 12 cents a liter here in about 10 months, Canada eh.