mods for better gas mileage

LPG used to be a good way to save $ on fuel, but the cost has gone up a lot. It is now about $.70/liter here in Canada, with gas at about $1.15/liter. Less BTU's in propane, so the difference is not as great as it looks. It is close to the point where we are paying the same for the BTU's, just they don't tax the propane as much.

There are other advantages to propane, like cleaner running, less wear, etc., but they are hard to figure in to the equation, especially when a car lasts as long as a Subaru does on gas. The engines already outlive the bodies, what is the point in making them last longer?

Conversion costs would be hard to recover. The high octane rating of the propane is hard to take advantage of with a Subie, as it is hard to raise the compression. If one could, it would help make up for the lower BTU content of the fuel. Would be good for a turbo (with higher boost a possibility) , but the propane mixers are not all that sophisticated, much less so than the MPFI, so you lose tuneability, power and mileage by converting from a decent gasoline injection system to a crude propane mixer.

There are gaseous injectors out there, but they are still in the preliminary stages, not too much available on the market yet. Maybe one day....