Vehicle Conversion Basics
A Ford Transit Connect converted to run on compressed natural gas.
A converted vehicle or engine is one modified to use a different fuel or power source than the one for which it was originally designed. In an alternative fuel vehicle (AFV) conversion, a conventional vehicle from an original equipment manufacturer (OEM) is altered to run on an alternative fuel like propane or natural gas.
Modifying a hybrid electric vehicle to operate as a plug-in hybrid electric vehicle is an example of an advanced vehicle conversion.
Dedicated and Bi-Fuel
OEM vehicles and engines can be converted to "dedicated" configurations, meaning they operate exclusively on an alternative fuel. They can also be converted to "bi-fuel" configurations that have two separate tanks—one for conventional fuel and another for an alternative fuel; EPA regulations refer to this configuration as dual-fuel. The desired fuel is usually accessed by flipping a switch to change tanks.
Other systems use fuel blends. Flexible fuel vehicles, for example, can run on a mixture of 85% ethanol and 15% gasoline (E85).
Conversion Systems Installation
Conversion systems are installed by the system manufacturer or by a qualified system retrofitter (QSR), also referred to as an upfitter or installer.
Vehicle owners and fleet managers interested in pursuing a conversion must work with the manufacturer or an authorized representative. The actual conversion work must be performed by a licensed technician associated with the manufacturer that holds the relevant emissions-related certifications and tampering exemptions.
Manufacturers should provide a comprehensive training program and detailed documentation to their own technicians as well as to QSR technicians to ensure that equipment and components are installed properly. Technicians installing equipment and components should be experts in the fuel or technology they are working with. The QSR is accountable for the integrity of the conversion system components. It is the manufacturer's responsibility to ensure the equipment meets the appropriate emissions standards.