Converting Gas Cars to Natural Gas or Propane

Converting a car to natural gas or propane is environmentally friendly.

Converting a car to natural gas or propane is an environmentally friendly way to run your car. Cars modified in these ways emit less pollutants. In the long term it can save money, but be sure that your car has enough miles on it to make the initial costs of the switch worth it. Although methods vary depending on which conversion kit you buy, the same principles apply for most cars when changing to a propane system.

Things You'll Need

• Conversion kit
• Propane

Instructions

1. Decide which of the two types of conversion system you want. An open-loop system does not control electronics while a closed-loop system incorporates a sensor that provides continuous performance data. The closed-loop system can also adjust the fuel-to-air ratio when needed.

2. Buy a conversion kit. This kit should include actuators, electronics, a fuel controller (carburetor), software, tank and valves. Make sure to check the kit you buy will work with your car and your engine.

3. Install a liquid propane tank in the trunk of your car. If you are fitting a van or truck, this may change.

4. Change the engine according to the conversion kit instructions. The main things to modify will be the cam timing and compression ratio.

5. Install an electronic shut-off valve. This will stop the propane flow when the car is turned off which could be important in the case of an accident.

6. Add fuel to the car and check the system for leaks. The most common areas for this is near the filter.

Tips & Warnings

• Make sure to run the hoses so they will not get damaged by road irregularities.

• Start with a well-maintained vehicle. The process is simpler when the car doesn't have any problems before you convert it.

• The closed-loop system is more expensive than the open-loop system.

• Check your original car warranty. Some states require conversion kit manufacturers to provide a warranty, by installing one of these kits you may be voiding the original. Check particularly that it covers the propane system and any failures caused by it.

• When you maintain your car, keep a special look out for damage to spark plugs. These are the source of many problems in a converted car.

References

• Car Talk: Ideas From the Fringe
• Canadian Auto: Propane or Natural Gas?
• Natural Gas: Natural Gas in the Transportation Sector
• Mother Earth News: Propane Conversion: How to Make LPG Cars

Resources

• National Propane Gas Association