i know they have made propane cars before and in some countries they use them a lot and it has been around for a while but here is this interesting article:
http://www.autoblog.com/2007/04/13/r...powered-f-150/

 

I just can't believe that you will still have the same horsepower and torque as with regular fuel. I had natural gas on my old ranger and that thing was gutless! But it was awesome putting $7 worth in every 2 weeks! Now I'm spending more than that a day. This should be a nice alternative though if you have the extra dough.

 

Propane has more energy content than NG. I dont know exactly how it compares to gasoline, but from dealing with generators, they are de-rated when using NG as a fuel.

 

This truck is nothing like any of the propane fuelled vehicles you've ever seen before because it supplies propane to the engine very much like modern Ford gasoline injection systems. Because the propane is injected directly into each port as a LIQUID, the volumetric efficiency of the truck should be the same as or better than its gasoline counterpart. In case you've had experience with the earlier Ford propane systems, the fuel system on this truck is completely different in every regard than the GFI gas injection fiasco that Ford tried years ago.

The key to maximizing the power in any engine is to maximize the number of oxygen molecules trapped in the combustion chamber. The amount of energy in the fuel is not important with respect to how much power the engine makes. Remember, alcohol has less energy per gallon than gasoline but is still commonly used as a racing fuel.

The old propane systems have lower power for 2 reasons: 1) the fuel is metered into the engine as a gas which displaces air in the intake manifold and 2) the propane mixers typically start off supplying a lean mixture that becomes ideal for maximum power only at maximum air flow.

The liquid injected propane displaces a minimal amount of air and actually cools the air as it evaporates just like gasoline. However, the cooling effect (latent heat of vaporization) is greater for propane (193.1 BTU/lb) compared to gasoline (~150 BTU/lb) so that propane has a stronger effect on improving volumetric efficiency.

The LPI truck costs more than an ordinary F-150 but the 2005 Energy Bill offers an an alternative fuel tax incentive that offsets much of the additional cost. For more information, see http://www.propanetruck.us/

 

thats some pretty cool stuff...but the guy who typed that article can't type for ****! 6,5000?? goine??? and alot more in there.