Well, the system is setup to run on either gasoline or propane, by the flip of a switch, I can be running on propane at 60mph and flip the switch, the truck will loose power like if I let go of the gas pedal, and 2 seconds later you will feel the engine literally "kick in" with the other fuel. The system addons are:
1 OBD II controller PN 5929 from Dual Curve
1 IMPCO mixer
1 IMPCO gas pressure regulator
1 propane filter
1 200 liter gas tank (you can get them smaller, I wanted the autonomy of running 1,500 miles or more without seeing a gas station).
1 Dashboard selector switch
1 fuel sending unit (so the propane gas level will read out on the stock dash fuel gage indicator)
hoses, fittings and bla bla bla.
The OBD II controller will modify the timing and monitor/control the fuel ratio while running on propane, I installed a fuel ratio gage just as a precaution to see if the controller crapped out and I was sending to rich a mixture into the engine, this never happened. Flip the switch and open up the mixer throttle body with the lever (in the picture the switch is behind the lever) to function with gasoline, when I do this the fuel pump in the tank turns on, the inyectors turn on and a shut off valve cuts off the propane. The OBD II controller also bypasses so your PCM will revert the timing back to work on gasoline. On the picture looking into the hood there is a lot of contrast from the sun (lower 60's today, sorry about that you snow buried northeners).
Flip the switch again to shut down the pump & inyectors and turn on the 5929 controller, propane flows thru the shut off valve, goes into the pressure regulator which lowers the pressure from 300some psi down to ONE psi (coolant lines run through the regulator so it doesnīt freeze) and from there it goes to the throtle body thru a 1.5 inch hose to the top of the mixer (serves as a carburator) that replaces your stock housing right on top of the throttle body. The idle mix is controlled in the mixer with a servo and the full throttle mix is controlled on the regulator (you can see the two wire harness going into the regulator).
Fun ainīt it! The last picture I just took it because the cloud over the mountain looked awesome.
