Abstract: An exhaust system is provided for internal combustion engines which relatively improves the performance and reduces noise output of such engines. The system comprises a plurality of exhaust pipes which are operably flow connected to exhaust ports of the engine at one end thereof and to discharge pipes through a collection chamber at an opposite end thereof. The discharge pipes include a silencing device in the discharge ends thereof. A feedback mechanism is provided to divert a slip portion of the sonic wavefront and/or mass exiting through an exhaust pipe back toward the exhaust port associated with an interconnected exhaust port or in such a manner as to delay passage of the slip portion out of the discharge pipes or to delay the slip portion and direct same to a different discharge pipe for discharge. The feedback mechanism may be valve and computer controlled so as to add or delete the feedback as required to maximize operation of the engine and/or assist in operation of a vehicle powered by the engine.

Abstract: The disclosure is directed to an exhaust efficiency increasing apparatus incorporating crossover ducts between dual exhaust conduits extending from an engine having two cylinder banks. The ducts are disposed to communicate with upstream entry and downstream exit apertures on the exhaust conduits and cross in an "X". Since where the ducts are positioned affects engine torque, torque curves can be adjusted or changed by placing the crossover ducts near one end of a housing which is placed in the exhaust system and which can be reversed, end-to-end, to position the crossover ducts nearer to or further from the engine.

Abstract: A marine propulsion device comprising a propulsion unit including an internal combustion engine, the engine comprising a cylinder, a water jacket, a water jacket inlet port communicating with the water jacket, and a lower face having therein an exhaust outlet port communicating with the cylinder, the propulsion unit also including a drive shaft housing having a lower end, a gearcase connected to the lower end of the drive shaft housing, a propeller rotatably supported by the gearcase, a drive shaft which extends through the drive shaft housing and which includes an upper end driven by the engine and a lower end drivingly connected to the propeller, and an exhaust housing located at least partially within the drive shaft housing and connected to the lower face of the engine, the exhaust housing comprising an exhaust passage located interiorly of the exhaust housing and communicating with the exhaust outlet port, a water intake port, and a water intake passage located interiorly of the exhaust housing and commu

Abstract: The present invention provides methods to take advantage of the exhaust gas pulses in an exhaust system of a multi-cylinder internal combustion engine to increase the volumetric efficiency over the complete operating range of the engine. It solves the problems of other systems which are only able to gain a beneficial effect from the exhaust gas pulses over a limited range of the engine operating speeds, by providing a means of varying the exhaust pipe lengths, combinations, and cross-sectional area of the exhaust passages of the multi-cylinder internal combustion engine. By this means it provides an exhaust system in which the exhaust gas pulse frequencies can be varied over the entire operating range of the engine to obtain desirable pulse frequencies matching the cylinder exhaust timing for efficient extraction of the exhaust gases, improvement in volumetric efficiency and a higher maximum engine speed.

Abstract: In producing a homogeneous exhaust gas mixture equal portions of the exhaust stream from one cylinder bank and the exhaust stream from a second cylinder bank are combined and then fed to two catalysts. A lambda probe to control the fuel-air ratio is disposed in the path leading to one of the catalysts.

Abstract: An exhaust system for a V-type six-cylinder engine having first and second banks each having three engine cylinders. The exhaust system includes first and second exhaust systems which are respectively connected to the first and second banks to be supplied with exhaust gas from the engine cylinders. Each exhaust system includes an exhaust tube connecting a catalytic converter and a muffler. The exhaust tubes of the first and second exhaust systems are communicated at a predetermined position by a communicating pipe member. The predetermined position corresponds to location of antinodes of the resonance sound pressure modes in the respective first and second exhaust systems which modes are reverse in phase to each other, so that resonance frequencies in exhaust noise are cancelled thereby to effectively achieve exhaust noise reduction.

Abstract: An internal combustion engine is provided with an exhaust discharge system providing merging exhaust paths for discharging exhaust from individual cylinders into an exhaust cavity. A diverter valve is provided for selectively preventing merger of the exhaust from the individual cylinders prior to discharge, and an exhaust passage receives such diverted exhaust for discharge into the exhaust cavity. The diverter valve operates to divert exhaust at low speed operation, which provides satisfactory low speed exhaust tuning. The diverter valve is closed at high speed operation to allow the exhaust from the individual cylinders to merge prior to discharge, which provides satisfactory high speed exhaust tuning. The invention provides satisfactory exhaust tuning at both high speed and low speed operation, which heretofore had not been possible, to increase overall engine performance and power.

Abstract: A high output, multiple cylinder internal combustion engine embodying an improved exhaust system. Each cylinder of the engine discharges into a common expansion chamber through a respective exhaust pipe. Valves are provided for preventing the transmission of exhaust pressure pulses back to the combustion chamber exhaust ports.

Abstract: A high output internal combustion engine embodying an improved exhaust system including a reflective control valve that is positioned so as to prevent the existence of positive pressure at the exhaust port during certain running conditions so as to improve induction efficiency.

Abstract: Two embodiments of motorcycles having improved exhaust systems. In each embodiment, the motorcycle includes a V-type engine and the exhaust system provides substantially equal length exhaust pipes that merge into a common exhaust outlet and which are disposed beneath the clutch and on the opposite side of the engine from the generator. In addition, one embodiment discloses an oil filter that is disposed above the clutch so as to be protected from the heat of the exhaust pipes by the clutch.

Abstract: A motorcycle having an exhaust system with an exhaust control valve that is provided to improve engine mid-range performance without adversely affecting high range performance. Several embodiments of valves are disclosed, all of which include a valve member that is movable to a position to obstruct the flow through the exhaust gas but is also movable to an opened position wherein the exhaust gas flow is completely unobstructed. The exhaust control valve is suspended independently from the chassis and is configured so as to promote smooth flow of exhaust gases through it.

Abstract: An exhaust system (10) for a V-8 engine (14) mounted in a Porsche automobile (12) having a transaxle (16) with articulated axles (18). The exhaust system (10) comprises a pair of tubular headers (24) connected to an exhaust pipe (26) that extends over, around, and back under the transaxle (16) and is connected to a pair of reverse-flow mufflers (30). A balance tube (56) passes through a relieved portion (58) formed in the oil pan (22) of the V-8 engine to connect the exhaust pipes (26).

Abstract: Several embodiments of exhaust systems including reflective valve means interposed between the engine exhaust ports and an expansion chamber for improving performance at mid range and under low speeds. The reflective means comprise a plurality of rotatably supported members that are affixed to different shafts and the shafts are coupled together for simultaneous rotation. In some embodiments, the shafts are coupled by a linkage system and in another by means of a gear system. The shafts are journaled in either the same or separate valve housings and the valve members may be positioned on different horizontal planes or at an angle to each other to suit a variety of exhaust pipe configurations.

Abstract: An exhaust system of an internal combustion engine comprises for each outlet port of each cylinder a primary and a secondary exhaust pipe, which latter are connected at their opposite end in a junction box with the primary exhaust pipe of a succeeding cylinder in the firing order so that negative pressure is created in the second exhaust pipe and evacuation of exhaust gases from the succeeding cylinder in the firing order is enhanced.

Abstract: Several embodiments of motorcycle exhaust systems having forward and rearward exhaust pipes at least one of which extends transversely in a transversely extending expansion chamber for improving high speed performance. In addition, a variety of control valves are incorporated for varying the reflective area of the exhaust pipe ends so as to improve low speed and mid-range performance.

Abstract: An exhaust manifold includes an inner shell providing a first flange having an interior and exterior surface and an outer shell cooperating with the inner shell to define an interior region therebetween. The outer shell provides a second flange having an exterior surface which is situated in spaced-apart relation to the interior surface of the first flange to form a flange-receiving space therebetween. The flange-receiving space provides an access opening into the interior region intermediate the inner and outer shells. At least one baffle is situated in the interior region. The at least one baffle includes a mounting flange nested between the first and second flanges and positioned in the flange-receiving space to extend through the access opening so that a distal portion of the mounting flange is exposed to exterior surroundings outside of the interior region defined by the inner and outer shells. Configuration of the at least one baffle is disclosed for use in single and dual exhaust manifolds.

Abstract: Muffler apparatus for reducing both sound and particulates from exhaust gases from an engine. The apparatus includes resonating chambers, flow distribution structure and a cellular ceramic core filter module. Filter regeneration mechanism includes a heating element for heating the carbon on the inlet end of the ceramic core to combustion temperature. Particulate ignition resulting in regeneration occurs when combustion air is provided; in alternate embodiments, combustion air first flows through a preheater system. A processor unit with particular logic controls the apparatus.

Abstract: Several embodiments of exhaust systems including reflective valve means interposed between the engine exhaust ports and an expansion chamber for improving performance at mid range and under low speeds. The reflective means comprise a plurality of rotatably supported members that are affixed to different shafts and the shafts are coupled together for simultaneous rotation. In some embodiments, the shafts are coupled by a linkage system and in another by means of a gear system. The shafts are journaled in either the same or separate valve housings and the valve members may be positioned on different horizontal planes or at an angle to each other to suit a variety of exhaust pipe configurations.

Abstract: A control system for controlling a DC control motor which controls an internal combustion engine to follow-up a target value varying continuously depending on the operation condition of the engine, the current flowing through the DC control motor being controlled through pulse width modulation.

Abstract: Disclosed herein is an exhaust system for a two-cycle internal combustion engine including a rotatable crankshaft, first and second cylinders firing 180.degree. apart, and first and second exhaust ports communicating with the first and second cylinders respectively, the exhaust system comprising a substantially Y-shaped hollow exhaust pipe having first, second and third branches each having an open end and each being substantially equal in length to the distance an acoustical wave will travel through the exhaust pipe during an interval over which the crankshaft rotates through substantially ten to twenty degrees of rotation at a predetermined engine speed, the open ends of the first and second branches being adapted to be coupled to the exhaust ports of the first and second cylinders respectively.

Abstract: An exhaust gas control means for motorcycles or the like wherein an expansion chamber that contains an exhaust control valve is positioned beneath and to the rear of the engine. The individual exhaust pipes extend from the exhaust ports of the engine into the expansion chamber in proximity to the valve for improving the performance throughout the engine speed and load ranges.

Abstract: A control system for controlling an actuator which controls operation of an internal combustion engine in compliance with a target value varying continuously depending on the operation condition of the engine.

Abstract: An exhaust control device for an exhaust system for an internal combustion engine specifically applied to a motorcycle. An exhaust control device is incorporated that includes a single valve body having a plurality of exhaust gas passages that cooperate with each of a plurality of exhaust pipes that extend from the engine to the valve body. Parallel valve shafts are supported in the valve body and support valves that control the flow through the exhaust gas passages.

Abstract: An exhaust system for a multi-cylinder internal combustion engine has a tailpipe (13) which is divided by a partitioning wall or walls (14,15) into separate channels extending at least part-way of the tailpipe from its inlet end and with which the outlets of the primary exhaust channels in the manifold are separately connected. The structure of the exhaust system enables the exhaust system to be easily packaged within the engine compartment of a car, while enabling the lengths of the exhaust channels to be selected to enable advantage to be taken of the resonant phenomena for optimization of the engine torque and other engine characteristics.

Abstract: An exhaust device for use in an internal combustion engine includes a plurality of independent passages each connected to an exhaust port of a respective cylinder of the engine. At least one communicating passage is provided to connect the independent passages to each other at points upstream of a junction where the independent passages are joined together. The communicating passage permits the exhaust gases from one cylinder to flow into the independent passages for the other cylinders, thus lowering the gas temperature and improving fuel comsumption.

Abstract: An exhaust system is provided for internal combustion engines which relatively improves the performance of such engines. The system comprises a plurality of approximately equal length exhaust pipes which are operably flow connected to exhaust ports of the engine at one end thereof and to a collection chamber at an opposite end thereof. The system further includes discharge pipes which communicate between ambient atmosphere and the collection chamber. The exhaust pipes are grouped in sets such that each of the pipes in the set is generally axially aligned with one of the discharge pipes. The collection chamber has a cross-sectional area which is greater than the cross-sectional area of the exhaust pipes where they are attached thereto and converges to a smaller cross section at the opposite end thereof where the discharge pipes are attached thereto. The discharge pipes diverge away from the collection chamber and include a silencing device in the discharge ends thereof.

Abstract: In order to prevent the formation of a standing wave in the exhaust system one or more small transfer passages are formed either inthe body of the manifold or in the cylinder head. These passages permit exhaust pressure to be transmitted to the exhaust ports of the adjacent cylinders as well as into the exhaust conduiting. This destructively interferes with the formation of the standing wave and thus obviates the generation of exhaust noise.

Abstract: An improved multi-cylinder engine exhaust header and single exhaust pipe transition element. The transition element comprises separate cylinder exhaust input connections, a gas chamber, a single exhaust gas output and a thin blade member positioned between at least two separate exhaust input connections. The forward end surface of the blade member takes various configurations to aid the mixing of the exhaust gases from each separate cylinder in the gas chamber prior to exit from the exhaust gas output.

Abstract: An improved valve for use in an exhaust system to increase the performance of the engine throughout the entire engine and load speed ranges by providing reflective areas that cooperate with the individual exhaust pipes of the engine to reduce pressure pulses in the combustion chamber during valve overlap periods. A number of embodiments of compact valve constructions are shown that employ relatively short journaling shafts for minimizing the effects of thermal expansion.

Abstract: A number of embodiments of motorcycle exhaust systems including control valves for controlling the effective area of the exhaust pipes and for improving performance by preventing reflections from one exhaust pipe back into the cylinder served by another exhaust pipe. The valve means lies under the engine crankcase and the crankcase is formed with a recess for clearing the valve means and permitting air flow across it for cooling purposes. Various valving arrangements are disclosed as is a skid plate arrangement for protecting the valve means.

Abstract: An exhaust manifold for attachment to an engine having a plurality of exhaust ports is provided. The exhaust manifold includes an exhaust conduit that is in fluid communication with selected exhaust ports, with the exhaust conduit being formed to include separate primary and auxiliary outlet openings. The exhaust manifold also includes a tuning tube that is formed to include an inlet opening that is in acoustic communication with the auxiliary outlet opening, and an outlet opening. The exhaust manifold also has a chamber for providing a static volume that is in acoustic communication with the outlet opening of the tuning tube.

Abstract: Several embodiments of exhaust systems for motorcycles that improve the engine performance by positioning reflective valve members between an expansion chamber and the exhaust ports of the engine. In each embodiment, there are provided separate valve bodies with separate valve supporting shafts that are all controlled by means of a common controller either through a single or multiple servo motors.

Abstract: An exhaust manifold for an engine has sets of branches tuned to the fundamental frequency of exhaust products but with the branch length of the sets different so that the engine speed at which resonance occurs in each set is different. An inlet manifold has runner sets with each set being paired with an exhaust manifold branch set serving the same cylinders and tuned to effect resonance of combustion air in the runners at the same engine speed that resonance occurs in its associated exhaust branches.

Abstract: An installation for controlling the charge-cycle of an internal combustion engine which includes an inlet valve and an exhaust valve as main control devices as well as a shutter arranged in the suction system as auxiliary control device. At low rotational speeds and at full load of the engine, the shutter is so controlled that it rapidly opens a cross section in the suction system during the end phase of a suction operation. An increased velocity of the fresh gas flow and a pressure wave prior to inlet-closure is achieved thereby which increases the cylinder fill. This high pressure level can be maintained in the suction system or in the manifold between the auxiliary control device and the main control device by premature closing of the auxiliary control device.

Abstract: A tuned exhaust manifold is provided for attachment to an engine having a plurality of exhaust ports. The manifold includes an inner and outer shell joined together to form an exhaust chamber and an inwardly-opening flange-receiving space at a split line defined by the union of the inner and outer shells. Captive tuning baffles are dropped in place and positioned in the exhaust chamber to isolate individual engine exhaust ports for engine performance tuning. Each baffle includes a flange trapped in the space between the inner and outer shells to retain the baffle in a predetermined position within the exhaust chamber. The baffles are arranged in a predetermined pattern within the exhaust manifold to define separate passgeways extending from exhaust inlet openings formed in the inner shell toward one or more exhaust openings of the manifold. Tuning is accomplished by configuring and placing the baffles to control the flow of exhaust from each engine exhaust port through the exhaust manifold.

Abstract: A motorcycle having exhaust pipes of equal length and a V-type engine having a front and rear cylinder block. The exhaust pipe associated with the front cylinder block extending directly back to above the rear suspension mount. The exhaust pipe associated with the rear cylinder block extends downwardly to beneath and around the rear suspension mount and then upwardly to above the rear suspension mount. Both exhaust pipes terminate above the rear suspension mount to connect with mufflers which extend upwardly and rearwardly adjacent to the back stay structure. The exhaust muffler systems are fixed to the back stay structure adjacent the aft end thereof. Pillion step brackets are fixed at the intersections of the back stay structure with the center frame members to insure appropriate strength in both the mounting and remaining in the frame.

Abstract: An exhaust manifold for multi-cylinder, opposed piston engines includes a collector, a plurality of conduits, each connecting an exhaust port from a cylinder to the collector and each conduit includes a thermal expansion joint to permit differential thermal expansion between the engine body and the substantially hotter exhaust conduit and thus to avoid undesirable stresses in the conduits. Preferably, the expansion joint is formed by overlapping portions of conduit sections which include axial as well as radial clearances therebetween for thermal expansion. In the event that the engine is to be turbocharged, the manifold can be covered with a thermal blanket to prevent heat losses from the exhaust system. In such a case, the expansion joint includes a resilient seal member between the overlapping conduit portions which seals the conduit sections to each other despite substantially similar thermal growth in each of the insulated blanketed conduit sections.

Abstract: An engine apparatus comprising an internal combustion engine having a cylinder with an exhaust port, an exhaust gas passageway system communicating with the exhaust port for providing a first compressive wave arriving at the exhaust port prior to closure thereof, and an exhaust gas side branch for providing a second compressive wave arriving at the exhaust port after the first compressive wave and prior to closure of the exhaust port.

Abstract: A pair of front exhaust pipes are joined to a rear exhaust pipe by an exhaust pipe joint. The front exhaust pipes have downstream end portions projecting into the exhaust pipe joint so that between the outer walls of the downstream end portions and the inner walls of the exhaust pipe joint there are formed annular spaces for receiving reflected waves travelling in the upstream direction and limiting the propagation of the reflected waves into the downstream ends of the front exhaust pipes.

Abstract: A bypass passage interconnects intake manifold passages and has a bypass valve disposed therein for shifting the tuning point for inertia supercharging, the bypass valve being actuatable to close and open the bypass passage by a bypass valve actuator operatively connected between the bypass valve and an accelerator-responsive lever for closing the bypass valve when the engine load increases.

Abstract: A four cylinder, two-cycle engine (10) has an exhaust system formed in a die-cast cylinder block. The exhaust system includes four legs (25) connected to the exhaust ports (23) of the cylinders (12). The upper two legs join together, as do the lower two legs to form two exhaust branches (26) connected by an exhaust trunk (27). An exhaust outlet passage (28) connected to the trunk (27) to provide an outlet for exhaust gases. The exhaust system is formed to lie in a plane on the exhaust side of the cylinder block (16).

Abstract: An exhaust manifold for a four-cylinder in-line internal combustion engine provided with a turbocharger is disclosed wherein a first exhaust duct and a second exhaust duct are connected to an upper exhaust gas outlet of a turbocharger-mounting flange roughly symmetrically with respect to the center of the turbocharger installing flange. A single third exhaust duct is connected to the lower exhaust gas outlet of the turbocharger-mounting flange. In the exhaust manifold according to the present invention, it is possible to effectively utilize cyclic exhaust gas pressure variation to induce exhaust gas pressure resonance for boosting turbocharger performance.

Abstract: A system for collecting and catalytically cleaning exhaust gases from an engine which is particularly suited for an arrangement wherein the catalyst is in close proximity to the exhaust ports of the engine. Exhaust pipes are employed having common walls extending longitudinally therethrough to separate and convey exhaust gases from two separate cylinders to a common manifold. The manifold is arranged to provide a mixing of the exhaust from a plurality of cylinders and to direct that homogeneous flow to the catalyst. A restriction is provided at the outlet of the manifold chamber and before an expansion chamber into the catalyst. This outlet and the expansion chamber are designed to provide maximum efficiency in distribution of gases to the catalyst and also provide minimum gas flow disruption and back pressure.

Abstract: A three cylinder, two-cycle engine 10 has a tuned exhaust system formed in a die-cast cylinder block 14. The exhaust manifold is formed by a cavity on the exhaust side of the cylinder block 14 with an exhaust gas outlet passageway 30 formed in the head end of the block 14.

Abstract: An exhaust system for a multicylinder motorbike internal combustion engine. Each cylinder has a respective exhaust pipe. The pipes merge and discharge into a chamber, from which chamber a plurality of silencers, fewer in number than the cylinders, discharges exhaust gases to the atmosphere.

Abstract: An exhaust system for a motorcycle having at least two exhaust conduits connected to different cylinders of a multiple cylinder motorcycle engine. Each exhaust conduit includes a curved flow divider for directing a portion of the exhaust gases through a crossover pipe for passage through the other exhaust conduit.

Abstract: A motorcycle has an engine with two banks of cylinders. One bank is forward of the other, and its exhaust pipe or pipes passes forwardly, downwardly, and outwardly of the frame, and then rearwardly beneath the side of the engine to reach a muffler and tailpipe. The frame includes a pivoted fork-like rear section with a power transmission. The rear exhaust pipe or pipes extends rearwardly and downwardly between the arms of the rear section, and makes connection with the muffler. In another embodiment for engines with multiple cylinders in each bank, the rear exhaust pipes cross over one another, and extend downwardly outside of the arms. They may also be elongated inside the muffler so the lengths of the forward and rear exhaust pipes are equal. They can connect with one another so as to share outlets into the muffler.

Abstract: Method and exhaust manifold for damping the pressure oscillations in an exhaust manifold of an internal combustion engine, consisting in throttling the gas flow in the vicinity of the cylinder outlet and then in accelerating the gases flowing in the manifold by providing a uniform flow section in the manifold substantially smaller than that of the cylinder bore.

Abstract: An exhaust manifold assembly for an internal combustion piston engine employs one exhaust tube for each cylinder and a collection chamber for each pair or larger group of exhaust tubes. Each collection chamber is connected to a plurality of exhaust tubes so that the exhaust timing spacing is the same in each collection chamber. A single exhaust reaction chamber is fed from pipes carrying the discharge from each collection chamber. The effect is to reduce backpressure and to improve scavenging efficiency while maintaining relatively high exhaust gas temperature for purification efficiency. The upstream end of each exhaust tube is supported and sealed within an engine exhaust port and the discharge end of each exhaust tube is slidably received within its collection chamber.

Abstract: A motorcycle has an engine with two banks of cylinders. One bank is forward of the other, and its exhaust pipe or pipes passes forwardly, downwardly, and outwardly of the frame, and then rearwardly beneath the side of the engine to reach a muffler and tailpipe. The frame includes a pivoted fork-like rear section with a power transmission. The rear exhaust pipe or pipes extends rearwardly and downwardly between the arms of the rear section, and makes connection with the muffler. In another embodiment for engines with multiple cylinders in each bank, the rear exhaust pipes cross over one another, and extend downwardly outside of the arms. They may also be elongated inside the muffler so the lengths of the forward and rear exhaust pipes are equal. They can connect with one another so as to share outlets into the muffler.