Vapor-Handling Capacity of Automobile Fuel Systems

THIS report covers information obtained on vapor lock, fuel-line temperatures and vapor-handling capacity as the result of road tests with 46 cars. The investigation was conducted under the auspices of the Cooperative Fuel Research Steering Committee in cooperation with the Natural Gasoline Association of America. The general procedure consisted in operating the car with samples of gasoline of increasing vapor pressure until vapor lock occurred.

The development of a method for the evaluation of the vapor-handling capacity of fuel systems under various operating conditions has been of material assistance in analyzing the vapor-lock problem. The present work indicates that changes both in fuel-line temperatures and in vapor-handling capacity affect the permissible vapor pressures. It is still believed that lowering of fuel-line temperatures by changes in design of the fuel system is the most effective method of insuring freedom from vapor lock.