An apparatus is provided for regulating the inflow of fuel into an intake duct (19) of a controlled-ignition internal combustion engine through the utilization of a fuel injection valve (11) having an outlet (21) opening into the intake duct (19) downstream of a multiple position speed regulator valve (30). Conventional control mechanisms (29, 40) energize the fuel injection valve (11) as a function of the operating parameters of an associated engine. A fuel container (13) has an outlet connected by a pipe (12) to an inlet of the fuel injection valve (11), and a float valve mechanism (17) maintains a substantial uniform level of fuel (14) in the fuel container (13) which corresponds to the position of the fuel injection valve outlet (21) whereby the amount of fuel introduced into the intake duct (19) is proportional to the velocity of the air flowing therethrough and substantially absent pressurization from the fuel (14) within the fuel container (13).