Abstract: A dynamic variable intake tubing includes a dynamic swirl supercharging tube which has a tubular member. The tubular member has a through hole axially penetrated. Flow-guiding grooves which follow a forward helical course or a reverse helical course are disposed on an inner peripheral surface of the through hole. At least a bearing is disposed around an outer circumferential surface of the tubular member to enable the tubular member to rotate freely. Flow-guiding blades are disposed at an intake end of the tubular member for ushering in gas current and guiding the gas current to the flow-guiding grooves. The flow-guiding grooves speed up intake and render combustion complete while an engine is operating at high rotational speed. The dynamic variable intake tubing generates an appropriate back pressure while the engine is operating in low speed, thereby increasing torque output and enhancing the performance of the dynamic swirl twofold to fivefold.

Abstract: An intake tubing includes a tubular member having a number of helical protuberances and a number of helical grooves formed in an inner peripheral surface, an inlet end for receiving fluid, and an outlet end for coupling to an engine. The helical protuberances and the helical grooves of the tubular member may guide the fluid to flow through the tubular member in great speed and to increase power of the engine when the fluid flows quickly toward the inlet end of the tubular member, and to generate eddy current and to lower the flowing speed of the fluid when the fluid flows slowly toward the inlet end of the tubular member, in order to economize fuel or fluid.