It likely costs $$$ to convert my engine just like it would take $$$ to buy a hybrid. I'd like to be able to pay less in gas each month (for my own selfish reasons - i.e. I work incredibly hard for my $$ and make so little); however, I can barely afford rent, let alone spending thousands on a new car or engine.
I installed a propane conversion kit on my Baja Bug for less than $300. I can run on gas or propane at the flick of a switch. Liquefied Natural Gas can be substituted for propane without any problem.
The only catch is labor. If you can do the work yourself it's an easy weekend project. If you have to take your car to a shop it could be expensive.
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