A thermal choke, includes (1) a body, comprising a heat conductive material, (2) an electric heater, on or in the body, (3) a temperature sensor, on or in the body, and (4) a fin, in a channel surrounded by the body. The thermal choke is configured to fit between a throttle assembly and a cylinder of a spark ignition engine.

Disclosed in this description are modifications either attached to, or made as part of, accelerator pump discharge nozzles, tubes or pipes. These modifications include the use of a fuel atomizer plate for carburetors as either a separate device placed beneath or on top of an accelerator pump discharge nozzle, tube or pipe, or simply located in the fuel stream of an accelerator pump discharge nozzle, tube or pipe, or a fuel atomizer plate for carburetors made as a single unit along with an accelerator pump discharge nozzle, tube or pipe. All are used on standard engines and assist in the atomization and homogenization of incoming fuel with incoming air to improve engine performance

Disclosed in this description are modifications either attached to, or made as part of, accelerator pump discharge nozzles, tubes or pipes. These modifications include the use of a fuel atomizer plate for carburetors as either a separate device placed beneath or on top of an accelerator pump discharge nozzle, tube or pipe, or simply located in the fuel stream of an accelerator pump discharge nozzle, tube or pipe, or a fuel atomizer plate for carburetors made as a single unit along with an accelerator pump discharge nozzle, tube or pipe. All are used on standard engines and assist in the atomization and homogenization of incoming fuel with incoming air to improve engine performance

A throttle body fuel injection system and method that is arranged to easily replace four-barrel carburetors includes a throttle body assembly with four main bores, each with a throttle plate and an associated fuel injector. Each injector feeds fuel into a circular fuel distribution ring via a fuel injection conduit, which introduces pressurized fuel into the air stream. The fuel distribution rings and bores have profiles that avoid constrictions for to prevent low pressure zones according to the Venturi effect. Fuel is injected through downward-facing outlets at or near the bottom end of the rings. The fuel injection rings are two-piece, each formed of an insert pressed into an outer housing. The insert includes axial grooves intervaled about its exterior circumference of insert that are joined by a circumferential groove formed about the insert. The grooves are in fluid communication with a conduit that supplies fuel from a fuel injector.

A throttle body fuel injection system and method that is arranged to easily replace four-barrel carburetors includes a throttle body assembly with four main bores, each with a throttle plate and an associated fuel injector. Each injector feeds fuel into a circular fuel distribution ring via a fuel injection conduit, which introduces pressurized fuel into the air stream. The fuel distribution rings and bores have profiles that avoid constrictions for to prevent low pressure zones according to the Venturi effect. Fuel is injected through downward-facing outlets at or near the bottom end of the rings. The fuel injection rings are two-piece, each formed of an insert pressed into an outer housing. The insert includes axial grooves intervaled about its exterior circumference of insert that are joined by a circumferential groove formed about the insert. The grooves are in fluid communication with a conduit that supplies fuel from a fuel injector.

A thermal choke, includes (1) a body, comprising a heat conductive material, (2) an electric heater, on or in the body, (3) a temperature sensor, on or in the body, and (4) a fin, in a channel surrounded by the body. The thermal choke is configured to fit between a throttle assembly and a cylinder of a spark ignition engine.

A thermal choke, includes (1) a body, comprising a heat conductive material, (2) an electric heater, on or in the body, (3) a temperature sensor, on or in the body, and (4) a fin, in a channel surrounded by the body. The thermal choke is configured to fit between a throttle assembly and a cylinder of a spark ignition engine.

A gaseous fuel-air mixer includes an outer shell, an inner shell, and a fuel chamber rib. The outer shell includes an air intake and a fuel intake. The air intake is configured to receive air. The air intake has an air outlet. The fuel intake has a fuel inlet that is configured to receive fuel. The inner shell includes an inner shell intake that is configured to separately receive the air from the air outlet and the fuel from the fuel intake and to provide a gaseous fuel-air mixture. The inner shell cooperates with the outer shell to define a fuel intake collecting chamber that is configured to receive the fuel from the fuel inlet and a fuel intake concentrating chamber that is configured to receive the fuel from the fuel intake collecting chamber and provide the fuel to the inner shell intake.

A gaseous fuel-air mixer includes an outer shell, an inner shell, and a fuel chamber rib. The outer shell includes an air intake and a fuel intake. The air intake is configured to receive air. The air intake has an air outlet. The fuel intake has a fuel inlet that is configured to receive fuel. The inner shell includes an inner shell intake that is configured to separately receive the air from the air outlet and the fuel from the fuel intake and to provide a gaseous fuel-air mixture. The inner shell cooperates with the outer shell to define a fuel intake collecting chamber that is configured to receive the fuel from the fuel inlet and a fuel intake concentrating chamber that is configured to receive the fuel from the fuel intake collecting chamber and provide the fuel to the inner shell intake.

A thermal choke, includes (1) a body, comprising a heat conductive material, (2) an electric heater, on or in the body, (3) a temperature sensor, on or in the body, and (4) a fin, in a channel surrounded by the body. The thermal choke is configured to fit between a throttle assembly and a cylinder of a spark ignition engine.