Abstract: By equipping a header wherein hollow pipes are welded to a rectangular plate used to mount the header with spaced apart extensions of the welds joining the pipes to the plate located on opposite sides of the bolt holes formed in the plate to mount it on an engine, wherein all the welds are ground flat so that the flattened surfaces of the extensions and the welded ends of the pipes lie in a common plane, it is thereafter possible to connect (bolt) the header to the engine's cylinder head employing bolts without the necessity of gaskets.

Abstract: An integrated manifold, muffler, and catalyst device for an engine uses perforated ducts surrounded by a resonator volume. Exhaust flow is routed from the exhaust ports by the ducts to a close coupled catalyst. The combination of the perforated ducts with the resonator volume and close coupled catalyst reduces exhaust flow restriction while at the same time increasing catalyst performance and reducing noise emissions.

Abstract: An exhaust manifold for an engine includes a manifold body 7 having a plurality of branch pipes and a common collecting chamber integrally connected to the branch pipes and communicating with an exhaust emission control device is divided into an upper half and a lower half at a boundary face extending in a direction of arrangement of the branch pipes. The upper and lower halves are made of steel plates and welded to each other. In the exhaust manifold, a welding mating coupler is formed by outer edges of the upper and lower halves, and a welding stepped superposing coupler is formed by inner edges of the upper and lower halves. Thus, during welding, it is possible to limit the misalignment of the upper and lower halves in a direction along the boundary face and the misalignment of the upper and lower halves in a direction perpendicular to the boundary face by cooperation of the mating coupler and the stepped superposing coupler.

Abstract: An exhaust manifold with several inlet ports and a combination of diffuser and nozzle portions associated with each inlet port for producing a high flow rate and a low pressure drop from entry to exit. The diffuser and nozzle portions are in series and designed into the manifold at each inlet port and slightly upstream of the next downstream positioned inlet port. The diffuser portion decreases the velocity of exhaust gasses as they enter the manifold and are then turned substantially ninety degrees into a longitudinal direction of the manifold. This diffuser action slows the velocity and reduces pressure losses as the turn of exhaust flow is accomplished. The next in series nozzle portion increases the velocity of exhaust gases to cause the flowstream to jump past a neighboring downstream engine exhaust port. Resultantly, the flow through the manifold is improved and the pressure drop decreased which enhances engine performance.

Abstract: A muffler for an internal combustion engine has an expansion chamber (31, 32) into which exhaust gas from the engine is introduced. The expansion chamber has a double wall (32A), with an inner panel (42) of the double wall (32A) having exhaust gas discharge portions (42A, 42B, 42C, 42D) with respective blowout holes (61, 62, 63, 64) for introducing the exhaust gas from the expansion chamber (32) into an air space (Sb) in the double wall (32A). From the air space (Sb), the exhaust gas is vented to the ambient through a discharge hole (37A) in an outer panel (42) of the double wall (32A ). A spark arrester screen (72) covers the discharge hole (37A).

Abstract: A four-cycle engine is provided which is suitable for use in a vehicle or an apparatus such as a small jet boat to be operated on the premise that it often overturns, and which is simple in structure. An oil pan 22 is disposed below the bottom of a crankcase 13, the spaces in the components are communicated with each other via a communicating hole 27 which is formed in the bottom of the crankcase 13, and a cylindrical peripheral wall 26 which is downwardly extending from the bottom of the crankcase 13 toward the oil pan 22 is formed around the communicating hole 27 and is spacially separated from the side wall of the oil pan 22 by a distance.

Abstract: Disclosed herein is an internal combustion engine including a reactor including opposed first and second ends, an outer shell extending between the opposed ends, and a flow path extending between the opposed ends and including an entry opening at the first end, and a discharge opening at the second end, and an engine member including a plurality of spaced combustion chamber portions each including an exhaust port, an exhaust manifold communicating with the exhaust ports and with the entry opening and including a generally vertically extending open side including a portion closed by the reactor outer shell, and an outer wall spaced from the open side of the manifold and also engaging the outer shell of the reactor.

Abstract: An exhaust system for an engine having at least four exhaust ports firing in sequential order. The exhaust system includes an exhaust manifold having two collector sections which extend in substantial part in parallel side-by-side relationship to provide a compact construction. Each collector section is served by a pair of branch portions that communicate with respective cylinders where the cylinders collected firing at least 270 degrees from each other to minimize the effect of the exhaust pulses from one cylinder on the other cylinders.

Abstract: A hot pipe from an automobile manifold is shielded from other components in the engine compartment by attaching a two part shield around the pipe and clamping it in place. Each part is formed of two sheets of metallic material sandwiching therebetween a fibrous layer of heat insulating material. The layers of each of the shield parts are formed to a shape to conform to the shape of the hot pipe to be shielded prior to installation.

Abstract: A fan-type manifold for multi-cylinder internal-combustion engines has several first individual pipe sections which are connected in pairs to respective ones of second pipe sections. The first individual pipe sections are undeformed on the end and are cut off at a specific angle. The second pipe sections are produced by an internal high pressure deforming process. The first pipe sections are plugged into the second pipe sections at respective Y-type combining points to form Y-shaped connections and are sealingly welded to each other via surrounding fillet welds. One of the second pipe sections has an additional Y-type combining point for the lateral connection of the other second pipe sections, which are sealingly welded thereto via surrounding fillet welds.

Abstract: An improved header assembly for use in V-8 engines. In engines having eight cylinders, performance can be unexpectedly improved by utilizing an improved header assembly whereby the exhaust gas from each of cylinders 4 and 7 is routed by means of a by-pass tube to a specific area in a second stage collector while the exhaust gas from the remainder of the cylinders is routed to a first stage collector. Such an arrangement of tubes routing exhaust gas into first and second stage collectors creates smooth, non-turbulent exhaust gas flow through the collector resulting in greater engine horsepower and torque.

Abstract: Curved inlet pipes, which themselves are assembled from at least two curved individual pipes, are provided in an exhaust manifold with sheet metal inlet pipes from the respective cylinder head outlet to a common exhaust gas outlet. As a result, the sum of the moments of resistance is substantially smaller, especially in the case of short, curved inlet pipes, which prolongs the service life of a sheet metal exhaust manifold.

Abstract: A number of embodiments of four-cylinder, four-cycle outboard motors having a compact exhaust system and yet one in which the exhaust pulses from one cylinder are not transmitted to other cylinders so as to interfere with their operation. This is accomplished by providing a series of paired exhaust manifolds with no two successive firing cylinders being served by the same manifold.

Abstract: An exhaust manifold of which each exhaust port is formed by a pipe member is disclosed. Each pipe member at one end portion has a wedge shape section. Each pipe member at the other end portion is connected to the cylinder head of an engine. The pipe members are abutted one another in the one end portion to form the merging portion of the exhaust manifold. A plurality of radial partition walls are formed in the merging portion by joining end surfaces of the pipe members one another. In the exhaust manifold, two adjacent partition walls among the partitions walls are arranged almost symmetrically around a plane which passes through the center of the merging portion and is parallel to a direction in which the largest force is generated by thermal expansions of the exhaust ports.

Abstract: An exhaust manifold for conducting exhaust gas from an internal combustion engine including a collection pipe structure having branches with engine flanges at their ends for mounting to cylinder outlet ports of the engine and an outlet flange at the downstream end of the pipe structure for connection to an exhaust pipe. The collection pipe structure has in the area of the branches a cross-section with different diameters for first and second cross-sectional directions which are normal to each other so as to form a drop-like or oval cross-sectional area which, in a downstream direction, continuously changes until the two diameters are equal providing for a circular shape at the end of the collection pipe structure adjacent the outlet flange.

Abstract: An exhaust system for use with the engine (10) of a vehicle. The exhaust system includes a pair of catalytic converters (18) connected to separate exhaust streams, with each catalytic converter (18) including an outlet pipe (22) extending therefrom. A dual inlet muffler (24) includes a pair of inlet pipes (26) spaced to mount to the outlet pipes (22). A slip fit joint (32) connects one of the outlet pipes to an inlet pipe and a ball and flare joint (34) connects the other of the outlet pipes to the other inlet pipe; thus allowing for alignment and proper mounting of the exhaust system to a vehicle.

Abstract: A collector system for exhausts that uses a junction to merge the an engine's primary tubes in a linear arrangement. Thus, all exhaust gas passes cleanly through the unit with no interference or creating any hot spots than can fail. To help remove exhaust gas from the junction portion of the collector, a venturi pipe is installed in the system. This venturi acts to scavenge the junction pipe of any remaining exhaust before the next impulse come through the system. Finally, to eliminate the complex welding of the primary tubes and to guarantee a seal, a tube sheet is used. This tube sheet accepts each of the primary tubes. Each pipe is then welded to the tube sheet, which then fits over the end of the collector junction. The tube sheet is then welded to the junction and the system is sealed.

Abstract: An exhaust header system for an internal combustion engine having improved exhaust gas flow characteristics. Primary pipes extend from openings in a flange bolted to the engines exhaust ports. The primary pipes come together at a collector pipe into which the primary pipes extend slightly. The ends of the primary pipes are substantially parallel, uniformly spaced around the collector pipe axis and have end surfaces lying substantially in a single plane. A generally pyramidal transition piece has a base corresponding to, and secured to, the primary pile end surfaces so as to cover the area between the pipe ends. The pyramid apex extends along the collector pipe centerline toward the exit end. The length and cross section of the transition piece is selected to provide a smooth transition from the greater combined internal cross section of the primary pipe ends to the lesser cross section of the collector pipe exit end.

Abstract: An exhaust manifold has a plurality of double pipes, each of which includes an inner pipe and an outer pipe, and a collecting pipe to which each of the double pipes is connected. The outer peripheral portion of the outer pipe is secured to the collecting pipe, and a thermal insulating layer of air, which is formed as a closed space so that substantially no exhaust gas will penetrate it, is disposed on an inner peripheral side of the portion at which the outer periphery of the outer pipe is secured to the collecting pipe. Owing to the presence of the thermal insulating layer, heat is not transmitted to the welded joint directly via the inner and outer pipes.

Abstract: An exhaust component for an internal combustion engine includes a housing having an interior. Left and right inlet tubes are provided on an inlet end wall of the housing for conveying exhaust gases to the interior, and at least one outlet tube is provided on an opposite outlet end wall of the housing for conveying the exhaust gases from the interior. A first panel extending between top and bottom walls of the housing in a position intermediate the inlet and outlet end walls defines an outlet opening in fluid communication with the outlet tube. Second and third panels extend convergingly toward the outlet opening from left and right side walls of the housing in order to direct the exhaust gases toward the outlet opening. One embodiment includes both left and right outlet tubes that extend from the outlet end wall to the outlet opening covergingly so that both the left and right outlet tubes are in fluid communication with the outlet opening.

Abstract: An engine exhaust manifold and method of making it, comprising an exhaust port flange having a plurality of exhaust port openings therethrough, a base half shell having a pair of elongated, spaced walls terminating in elongated free ends, a plurality of runners attached to the port flange at the exhaust port openings, a liner half shell having a wall thickness less than that of the base half shell, having a pair of spaced walls terminating in elongated free ends overlapping the base half shell free ends, the liner half shell being oriented opposite the orientation of the base half shell to form a flow passage therebetween, a jacket half shell having a thickness greater than that of the liner half shell, having a pair of spaced elongated walls terminating in elongated free ends, the jacket half shell extending over and encompassing the liner half shell but spaced therefrom to form an airgap therebetween except at the jacket half shell free ends and the liner half shell free ends, the jacket half shell free end

Abstract: An exhaust collector for collecting exhaust gases from a multiple cylinder combustion engine to a common flow includes primary tubes. To reduce mass and heat losses in the exhaust system, the peripheral walls of the collector are at least to a substantial part formed by the primary tubes.

Abstract: A method of forming a breakage resistant, erosion resistant ceramic liner for a part comprising the steps of, forming a liner of a ceramic material containing pores; filling the pores with a pre-ceramic polymer resin; and, firing the liner saturated with a pre-ceramic polymer resin at a temperature and for a time which converts the resin into a ceramic within the pores. The liner can be mechanically attached, adhesively bonded or, a metal part can be cast onto the liner by placing the liner within the metal casting mold for the part as a sidewall or integral element thereof. The invention also includes method for producing parts and liners of fiber reinforced ceramic matrix composite by a resin transfer molding process or the like wherein fiber preforms are saturated with liquid pre-ceramic polymer resin. The preforms are then polymerized in a mold, the part removed from the mold, and then fired to transform the polymer to ceramic. The process can also be employed to form hollow parts such as manifolds.

Abstract: A collecting portion for an exhaust manifold branch where a combined pipe portion including a plurality of pipes is welded to a collecting pipe wherein, (1) an intermediate member is provided between the combined pipe portion and the collecting pipe, (2) the collecting pipe has a portion that extends upstream, (3) a weld line formed at the downstream end of a partitioning wall is axially zigzagged, (4) a weld line is offset from the downstream surface of the combined pipe portion, (5) only one of the partitioning walls is curved, (6) downstream ends of the partitioning walls are smoothly convex, (7) an additional weld is formed in the partitioning wall, or (8) an intermediate member is welded at a half circumference of the combined pipe portion.

Abstract: A simple exhaust system is disclosed with improved operational reliability and an increased service life for a turbocharged internal combustion engine, in which system both the advantages of shock-wave charging and those of pulse-converter charging are used, depending on the operating state of the internal combustion engine. These advantages are achieved by virtue of the fact that extension pieces (12, 13) are formed for the shock pipes (6, 7) and are arranged upstream of the connection line (8, 9) furthest away from the exhaust turbine (5). Each shock pipe (6, 7) is connected to a corresponding extension piece (12, 13). The interconnection conduit/s (14) is/are formed between the extension pieces (12, 13). Each interconnection conduit (14) has a cross-sectional constriction (15).

Abstract: A thin-walled double pipe exhaust manifold comprises a double pipe consisting of a comparatively thin inner tube and a comparatively thick outer tube, both spaced apart from each other adiabatically through an aperture defined between these tubes. The inner tube is formed with at least one bead portion for relieving thermal stresses induced in the inner tube. To effectively reduce thermal stresses by way of thermal expansion or contraction, the bead portion is provided around each heat spot similarly to the temperature distribution of each heat spot.

Abstract: A pollutant reducing exhaust manifold for an internal combustion engine incorporating a catalytic converter therein. The manifold has a plurality of header pipes connected to and receiving exhaust gases from respective ones of a plurality of exhaust ports of an internal combustion engine. The header pipes are connected to a single chamber with an outlet therefrom connected to an exhaust pipe as well as a catalytic converter structure having a catalyst disposed on a supporting substrate disposed in the chamber between the inlet(s) and the outlet so that all exhaust gases from the engine must pass through the catalytic converter structure. The catalytic converter operates at higher temperatures for increased efficiency and comes to operating temperature virtually immediately.

Abstract: A four stroke internal combustion engine (10) having a V-type configuration with eight cylinders (11). The firing order of the cylinders is such that a relatively balanced mechanical operation occurs. A right manifold (16) and a left manifold (18) connect to the right bank (12) and left bank (14) respectively. Each of the manifolds (16, 18) includes first and second primary runner. For the right bank (12), the first primary runner (22) connects to one cylinder and the second primary runner (24) connects to the other three cylinders. The separate primary runners (22, 24) are configured such that no two cylinders within a given primary runner will begin to exhaust within 180 of each other. The left bank is similarly configured. In this way, interference of exhaust pulses between cylinders is avoided, leading to equal cylinder to cylinder operation with less back pressure, while still using minimal space around the engine.

Abstract: An exhaust manifold for an internal combustion engine with at least two cylinders includes at least two adjacent connection branches which are interconnected by collection pipe sections having an expansion compensating bellows for accommodating differential thermal expansion therebetween and a gas flow guide pipe structure which extends into the bellows. At least one of the collection pipe sections comprises a multi-layered pipe wall with which the expansion compensating bellows is integrally formed.

Abstract: An exhaust manifold for an engine is made of all fiber reinforced ceramic matrix composite material so as to be light weight and high temperature resistant.

Abstract: An exhaust manifold for an internal combustion engine includes an inner duct with flanges for connection to an engine. The inner duct is enclosed by an envelope consisting of two shells which are interconnected at their edges by seams. Between the inlet flanges, the seams are disposed at a substantially greater distance from the inner duct than in other areas such that, in a cross-sectional plane disposed between, and extending normal to, the flanges, the envelope has drop-like shape.

Abstract: A sealing structure in an exhaust system of an internal combustion engine includes a gasket which is clamped between a cylinder head and a flange fastened to the cylinder head and which has a sealing portion surrounding an exhaust port opening into a side of the cylinder head, and an exhaust pipe which is curved and coupled to the flange and which is in communication with the exhaust port. In this sealing structure, the sealing portion of the gasket is formed into an endless shape to surround said exhaust port, such that the distance between the sealing portion and a peripheral edge of the exhaust port, at least at a location substantially corresponding to a projected position of the exhaust pipe on the flange, is larger than the distance at other locations. Thus, it is possible to prevent or minimize the deterioration of the sealing portion of the gasket due to heat, while avoiding an increase in size of the section associated with the exhaust system.

Abstract: A multi-cylinder internal combustion engine having at least one cylinder head with intake and exhaust ports and having an intake manifold with a common chamber and individual intake runners leading from the common chamber to the intake ports. The individual runners each have interior wall surfaces which are rifled to produce a swirling flow as the intake gases move through the individual intake runners from the common chamber to the intake ports of the cylinder head. This rifling is in the form of a plurality of helical vanes, with the helix being tighter near the intake port than near the common chamber. The helical vanes comprise a first set of helical vanes that extend from adjacent the intake ports to adjacent the common chamber and a second set of helical vanes that extend from adjacent the intake ports to a position intermediate the intake ports and the common chamber. An improved exhaust manifold is also disclosed for use with the internal combustion engine.

Abstract: A method of forming a breakage resistant, erosion resistant ceramic liner for a part comprising the steps of, forming a liner of a ceramic material containing pores; filling the pores with a pre-ceramic polymer resin; and, firing the liner saturated with a pre-ceramic polymer resin at a temperature and for a time which converts the resin into a ceramic within the pores. The liner can be mechanically attached, adhesively bonded or, a metal part can be cast onto the liner by placing the liner within the metal casting mold for the part as a sidewall or integral element thereof. The invention also includes method for producing parts and liners of fiber reinforced ceramic matrix composite by a resin transfer molding process or the like wherein fiber preforms are saturated with liquid pre-ceramic polymer resin. The preforms are then polymerized in a mold, the part removed from the mold, and then fired to transform the polymer to ceramic. The process can also be employed to form hollow parts such as manifolds.

Abstract: An exhaust system for an engine comprising an exhaust manifold which has an outer casing and an inner casing spaced from the outer casing. The inner casing comprises a collecting portion and inner pipes. The collecting portion of the inner casing is stationarily supported by the outer casing. The upstream end portions of the inner pipes of the inner casing are axially movably supported by the outer casing.

Abstract: An exhaust gas pipe for multicylinder, supercharged internal combustion engines has an outer gas-tight casing (2) and an inner hot gas pipe (1) made up of segments (5) of cast parts securable by screws (8) which project into the casing (2) from the outside.

Abstract: The design and construction of past exhaust port liners with heat insulation capabilities have had to become more simple in order to reduce costs. However, less costly exhaust port liners may have inferior heat insulation capabilities. The present invention overcomes this and other problems with a means for encapsulating an insulating layer of material. The encapsulating means is composed of fiberglass cloth with the ability to withstand high temperatures. A blanket is formed when the fiberglass cloth encapsulates the insulating layer. The blanket is stitched in a quilted pattern to form a plurality of individual pockets. The blanket is wrapped around a ceramic body of a port liner. The quilted stitching pattern, due to separating the insulating layer into the plurality of individual pockets, protects the pockets individually. If damage should occur to one of the plurality of pockets, the insulating layer would remain intact within the remaining plurality of pockets.

Abstract: A damped heat shield for a high temperature portion of a vehicle exhaust system. The heat shield has inner and outer metal layers of substantially different thicknesses and substantially different resonant frequencies, which causes the shield to damp vibrational energy and reduce radiated sound energy and noise. Between the metal layers is a layer of sound and heat shielding material such as aluminum foil or ceramic fiber paper. The metal layers are preferably stainless steel, cold rolled steel, aluminized steel, aluminum-clad steel, or aluminum. If cold rolled steel is used, the exterior of the shield is preferably coated with a corrosion-resistant coating.

Abstract: An exhaust manifold in which a plurality of branch tubes at an inlet side are connected to a collecting tube at an outlet side, and in which the fluid flows from the branch tubes to the collecting tube, wherein a volumetric chamber is provided between at least a pair of the branch tubes in communication with the branch tubes, with the volumetric chamber being gradually increased in its cross-sectional area in a fluid flowing direction. An exhaust manifold formed of upper and lower members comprises a branch tube having a bend. The upper lower members are interconnected by joining flanges having a broader width in the vicinity of the bend than other joining flange portions.

Abstract: To provide an exhaust pipe structure capable of arranging a plurality of exhaust pipes in a restricted space inside a cover and suppressing the discoloring of the cover due to an increase in the temperature of the cover. Each of a plurality of exhaust pipes introduced from each cylinder of a multi-cylinder engine includes a double-pipe structure of an outer pipe and an inner pipe. The exhaust pipes pass inside the cover in such a manner that at least one exhaust pipe near the inner side surface of the cover is left as being of the double-pipe structure, and at least each of the remaining exhaust pipes has a portion of a single-pipe structure.

Abstract: An exhaust manifold joint includes a number of like exhaust manifold segments mounted to a corresponding number of cylinder heads of a large diesel engine. The exhaust manifold segments slip relative one another to accommodate thermal growth differentials between the exhaust manifold segments and the cylinder head. The exhaust manifold segments are further mounted to the cylinder head via fasteners that extend through a bolt hole of the exhaust. manifold. The bolt hole incorporates a reverse counterbore at the manifold to cylinder head attachment to move loading of the fastener away from the attachment, thereby resulting in elastic deformation rather than yielding of the fastener during loading of the fastener.

Abstract: The design and construction of past port liners with heat insulation capabilities have had to become more simple in order to reduce costs. However, less costly exhaust port liners may have inferior heat insulation capabilities. Additionally, port liners cast into a cylinder head of an internal combustion diesel engine must endure the stresses associated with the high casting temperatures of cast iron. The present invention overcomes these and other problems by utilizing a ceramic port liner containing a low temperature softening phase. The ceramic port liner is surrounded by a blanket formed when a fiberglass cloth encapsulates an insulating layer of material. The ceramic port liner and surrounding blanket are cast within a cylinder head. During the casting process, the ceramic port liner remains in a softened state. As the casting cools, the ceramic port liner returns to a regular solid state at a progressively sufficient thermal rate to protect it from damage.

Abstract: A number of embodiments of exhaust systems for outboard motors including a combined catalyst bed and exhaust manifold forming member affixed within the cylinder block of the engine so as to be readily detachable for servicing. This combined member is provided with a separate cooling jacket for its cooling.

Abstract: An arrangement for silencing the exhaust gases discharged from a multi-cylinder internal combustion engine, wherein the exhaust gas is discharged in first and second streams from separate exhaust gas manifolds on opposite sides of the engine and the two streams traverse a different but equal lengthed path to be combined into a single stream to be presented to exhaust system components, such as catalytic converters and separate mufflers. In one embodiment, the streams pass through conduits integrally formed, in part, with through structure of a muffler. In other embodiments, the stream paths are equalized by being passed through conduits formed in closed shells.

Abstract: A number of embodiments of small personal watercraft each embodying a V-type engine. Arrangements are shown wherein the engine is mounted either with its output shaft extending in a longitudinal direction or in a vertical direction. Various placements for the engine are disclosed and in all embodiments a straddle-type seat is incorporated for accommodating at least the rider and in some instances additional passengers. Various types of exhaust systems including watertrap devices are incorporated and the watercraft is provided with a pair of fuel tanks in several embodiments that are disposed in longitudinal alignment with the seat and on opposite sides thereof for improving balance.

Abstract: The invention relates to an exhaust system for a W-12 reciprocating piston internal combustion engine with three rows of cylinders of four cylinders each, with outlet channels connected to the exhaust lines, in which there are two separate exhaust runs to which two cylinders per row of cylinders are connected in order to achieve a functional, structurally favorable system.

Abstract: A connector is provided for joining two upstream exhaust pipes with a downstream exhaust pipe and for substantially offsetting any difference in length that may exist in the upstream exhaust pipes. The connector includes first and second external shells that are secured on opposite respective sides of an internal divider plate. The external shells and internal plates cooperate to define unequal travel lengths within the connector to offset the unequal travel lengths of the upstream exhaust pipes leading to the connector. The two separate exhaust flows with travel lengths equalized by the connector converge with one another into a chamber defined by the connector, and exit from the connector through an outlet. Expansion of the converging exhaust gas streams into the chamber contributes to acoustical tuning of the exhaust system. The equal lengths of the respective exhaust gas streams also facilitates acoustical tuning performed by a downstream muffler.

Abstract: An exhaust control system having a plurality of exhaust manifolds is configured and arranged such that combustion of exhaust gases flowing therethrough is unhibited to the extent that the concentration of major pollutants (CO, HC, NO.sub.x) exiting from the tail pipe and into the environment is substantially reduced. The exhaust system utilizes pairs of primary pipes defining an upstream portion of an exhaust manifold which are coupled to exhaust ports whose respective valves provide fluid flow communication to only one of the primary pipes at any moment in time. A secondary pipe defining an downstream portion of the exhaust manifold is coupled to the outlet of the primary pipes through a connector. One-way valves permit atmospheric air surrounding the exhaust manifold to be drawn into each primary pipe proximate its inlet, and into the secondary pipe proximate the connector.

Abstract: An exhaust system for a supercharged internal-combustion engine in which of the exhaust-gas-carrying components, the exhaust gas pipes leading from the cylinder outlets to the turbines, or the turbines, or the turbines and the exhaust gas pipes are arranged jointly in an exhaust-gas-tight housing. Openings in the exhaust-gas-carrying components cause the space formed between the exhaust-gas-carrying components and the housing to be filled with exhaust gas. By way of a bypass pipe which is connected with the space and leads to the turbine, exhaust gas can be blown off from the space. A blow-off valve is arranged in the bypass pipe.

Abstract: A manifold catalytic converter for automotive engines includes a flange provided on a cylinder head of the engine with a plurality of installation openings formed therethrough corresponding to exhaust ports of the engine. Tubes are connected to the installation openings with the other end of each of the tubes being attached to the vessel of the catalytic converter, aligned along a line of installation which is slanted relative the longitudinal direction of the engine so as to reduce transmission of vibrations from the engine to the vessel of the catalytic converter in directions transverse to the axial direction of the engine.