Abstract: An exhaust manifold has a plurality of branched exhaust passages connected to respective exhaust ports of individual cylinders; a plurality of first collector segments each of which joins the branched exhaust passages for the cylinders which are not adjacent in the exhaust order sequence; a plurality of middle exhaust passages connected to the downstream of the first collector segments, respectively; and a second collector segment that joins the middle exhaust passages. In at least low and middle speed ranges in a high load region of the engine, a valve opening time of an exhaust valve is changed according to the engine speed so that a predetermined amount of a valve overlap period is ensured and that negative pressure waves from exhaust pressure pulses reach an exhaust port during the valve overlap period in a plurality of engine speed ranges.

Abstract: The present engine design can comprise one or more three-cylinder modules. Each module can comprise a left-hand combustion cylinder, a compression cylinder and a right-hand combustion cylinder. In an embodiment, the compression cylinder can function as a supercharger providing compressed air to the two combustion cylinders in order to improve performance and efficiency. Each module can comprise a specialized cylinder head comprising an intake air plenum configured to allow pressurized air to flow from the compression cylinder into each of the combustion cylinders. The flow of this pressurized air can be precisely controlled by valves that control airflow into and out of each of the three cylinders. Variable valve timing and computer controls can determine the exact amount of fuel, if any, which will be injected into the combustion cylinders to deliver high fuel economy while delivering an optimal level of power, horsepower and torque.

Abstract: An apparatus for reducing a pumping loss may include an auxiliary runner formed in an air-intake unit supplying air to a cylinder, wherein intake air may be temporarily stored in the auxiliary runner by using a flow of an exhaust gas during an exhaust stroke, and the intake air stored in the auxiliary runner may be supplied to the cylinder together with the air introduced to the air-intake unit during an intake stroke.

Abstract: The horizontally opposed center fired engine improves on the traditional design of the horizontally opposed engines and center fired engines with a better engine geometry. The present invention utilizes four pairs of opposing pistons to compress a larger volume of air-fuel mixture within four different cylinders. The four different cylinders are radially positioned around a center axle in order to achieve a perfectly symmetric engine geometry. The center axle consists of two different shafts spinning in two different directions, which could drastically reduce engine vibrations in the present invention. Engine vibrations are caused by a change in engine speed and result in a loss of energy. Due to the design, the present invention will only experience energy loss in the form of entropy and friction. Thus, the present invention can convert a higher percentage of chemical energy into mechanical energy than any other internal combustion engine.

Abstract: The present invention provides a dual six-stroke self-cooling internal combustion engine which utilizes a turbo and a cooling cylinder to compress cool air onto the engine head and reduce the engine temperature. The present invention greatly reduces the size and the manufacture cost of the cooling equipments such as radiator and intercooler by cooling the power cylinder from within. In addition, the present invention slightly increases the fuel efficiency and reduces the exhaust temperature.

Abstract: An improved two stroke, multiple cylinder engine having combustion chambers and a single exhaust conduit for discharging exhaust gasses from the combustion chambers. In accordance with one feature of the invention, the combustion chambers are unified to two groups and respective combustion chambers belonging to the same group are generally simultaneously fired by a firing system. Otherwise, the entire combustion chambers are generally simultaneously fired. In accordance with another feature, the exhaust conduit has an attenuation mechanism for positive pressure reflection waves generated in the exhaust conduit. In a preferred embodiment, the attenuation mechanism comprises an inner pipe tapered downstream and having a plurality of apertures.