Apparatus and methods for converting conventionally fueled engines to operate on an alternative fuel

A method of operating an internal combustion engine with an alternative fuel, the method comprising the steps of:

• providing a plurality of alternative fuel injectors in fluid communication with the alternative fuel;
• measuring the temperature of the alternative fuel;
• generating an intermediate alternative fuel injector control signal in response to the temperature of the alternative fuel and the energy content differential of conventional fuel and the alternative fuel;
• adjusting the intermediate alternative fuel injector control signal to a final alternative fuel injector control signal in accordance with the flow and operating characteristics of the alternative fuel injector;
• and
• synchronizing the final alternative fuel injector control signal among the alternative fuel injectors.

A method of converting a conventionally fueled internal combustion engine to operate with an alternative fuel, the engine having an electronic control module which generates a control signal to a conventional fuel injector, the engine also having a valve which cycles through a valve opening event, the method comprising the steps of:

• providing an alternative fuel injector in fluid communication with the alternative fuel;
• measuring the temperature of the alternative fuel;
• generating an intermediate alternative fuel injector control signal in response to the temperature of the alternative fuel and the energy content differential of conventional fuel and the alternative fuel;
• adjusting the intermediate alternative fuel injector control signal to a final alternative fuel injector control signal in accordance with the flow and operating characteristics of the alternative fuel injector;
• establishing the time (t.sub..alpha.) between the control signal to the conventional fuel injector and a point of the valve opening event;
• establishing the time (t.sub..beta.) between the point of the valve opening event and the optimum point at which to actuate the alternative fuel injector;
• adjusting the final alternative fuel injector control signal as a function of t.sub..alpha. and t.sub..beta. ;
• and
• transmitting the final alternative fuel injector control signal to the alternative fuel injector.

A method of converting a conventionally fueled internal combustion engine to operate with an alternative fuel, the engine having an electronic control module which generates a control signal to a conventional fuel injector, the method comprising the steps of:

• providing a plurality of throttle body alternative fuel injectors in fluid communication with the alternative fuel;
• measuring the temperature of the alternative fuel;
• generating an intermediate alternative fuel injector control signal in response to the temperature of the alternative fuel and the energy content differential of conventional fuel and the alternative fuel;
• adjusting the intermediate alternative fuel injector control signal to a final alternative fuel injector control signal in accordance with the flow and operating characteristics of the alternative fuel injector;
• and
• alternately transmitting the final alternative fuel injector control signal among the throttle body alternative fuel injectors.

A method of converting a conventionally fueled internal combustion engine to operate with an alternative fuel, the engine having an electronic control module which generates a control signal to a conventional fuel injector, the method comprising the steps of:

• providing an alternative fuel injector in fluid communication with the alternative fuel;
• measuring the temperature of the alternative fuel;
• generating an intermediate alternative fuel injector control signal in response to the temperature of the alternative fuel and the energy content differential of conventional fuel and the alternative fuel;
• adjusting the intermediate alternative fuel injector control signal to a final alternative fuel injector control signal in accordance with the flow and operating characteristics of the alternative fuel injector;
• varying the timing of the start of the final alternative fuel injector control signal as a function of the fuel flow rate demanded by the engine;
• and
• transmitting the final alternative fuel injector control signal to the alternative fuel injector.