INTERNAL COMBUSTION ENGINES AND INTAKE MANIFOLDS WITH PORTALINE INJECTION DEVICES FOR GASEOUS FUEL

Abstract

This document discloses internal combustion engines and intake manifolds with intake ports and port fuel injectors. Each cylinder receives charge flow from a first and a second intake port, and at least one fuel passage is configured to distribute gaseous fuel from a port fuel injector through each of the first and second intake ports to the combustion chamber.

Description

Cross-reference to related application:

[0001] This application claims priority to and the benefit of the filing date of U.S. Provisional Application No. 63 / 386,253, filed December 6, 2022, which is incorporated herein by reference. TECHNICAL FIELD

[0002] The invention relates to internal combustion engines and, more particularly, to intake manifolds configured to distribute gaseous fuel to the combustion chambers of an internal combustion engine. GENERAL STATE OF THE ART

[0003] A cylinder head for an internal combustion engine may include two intake valve openings into the combustion chamber, each opened and closed by a first and a second intake valve. The valve openings are connected to respective first and second intake ports, which distribute the charge flow from the intake manifold to the respective intake valve openings.

[0004] For internal combustion engines powered by gaseous fuel, a first fuel injector may be mounted to deliver fuel to a first intake port, and a second fuel injector may be mounted to deliver fuel to a second intake port. Fuel is injected into each intake port upstream of the combustion chamber of each cylinder of the engine. Both or just one of the port injectors may be used to deliver the required amount of gaseous fuel into the intake port for delivery to the combustion chamber in response to specific engine operating conditions. Under engine operating conditions that require the use of only one port injector to deliver the required amount of gaseous fuel, inadequate or inefficient mixing of gaseous fuel in the combustion chamber may occur.Therefore, further improvements in this technological area are desired. SUMMARY

[0005] Internal combustion engines and intake manifolds are disclosed that include first and second intake ports for providing boost flow to each cylinder of the engine. The intake manifold is configured to distribute gaseous fuel from a port fuel injector associated with either the first or second intake ports to each of the first and second intake ports.

[0006] In one embodiment, the internal combustion engine includes at least one cylinder having a combustion chamber. The internal combustion engine includes at least one port fuel injector operable to inject a gaseous fuel for delivery to the combustion chamber. The internal combustion engine includes an intake manifold configured to provide a charge flow to the combustion chamber. The intake manifold includes a first inlet port connected to a first port output and a second inlet port connected to a second port output. The first inlet port is configured to introduce charge flow into the combustion chamber through the first port output, and the second inlet port is configured to introduce charge flow fuel into the combustion chamber through the second port output.The intake manifold includes at least one fuel passage connecting the at least one port injector to each of the first inlet port and the second inlet port upstream of the first port exit and the second port exit. The at least one fuel passage is configured to distribute gaseous fuel injected by the at least one port injector to each of the first inlet port and the second inlet port for delivery to the combustion chamber through each of the first and second port exits.

[0007] In one embodiment, an intake manifold is provided for distributing a charge flow to an internal combustion engine. The intake manifold includes a first inlet port for receiving a first portion of the charge flow and a second inlet port for receiving a second portion of the charge flow. The first inlet port is configured to provide the first portion of the charge flow, and the second inlet port is configured to provide the second portion of the charge flow, respectively, to a combustion chamber of the internal combustion engine. The cylinder head includes at least one port injector inlet. At least one fuel passage connects the at least one port injector inlet to each of the first inlet port and the second inlet port.

[0008] This summary is provided to introduce a selection of concepts further described below in the illustrative embodiments. This summary is not intended to identify central or essential features of the claimed subject matter, nor is it intended to be used as a means of limiting the scope of the claimed subject matter. Other embodiments, forms, objects, features, advantages, aspects, and benefits will be apparent from the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram of an internal combustion engine according to an embodiment of the present disclosure. Fig. 2 a schematic view through a cylinder of the internal combustion engine from Fig. 1, which shows an intake manifold and port fuel injector assembly according to an embodiment of the present invention. Fig. 3 is the intake manifold and intake manifold fuel injector assembly of Fig. 2, which shows the injection of fuel from only one of the port fuel injectors delivered to each of the intake ports. Fig. 4 is a schematic perspective view of a fuel passage arrangement between the inlet ports according to an embodiment of the present invention. Fig. 5 is a schematic view of a fuel passage arrangement between the inlet ports according to another embodiment of the present invention. DETAILED DESCRIPTION

[0009] To promote an understanding of the principles of the present invention, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe them. It should be understood, however, that no limitation of the scope of the invention is intended thereby; any changes and further modifications in the illustrated embodiments, and any further applications of the principles of the invention illustrated therein, as would commonly occur to one skilled in the art to which the invention pertains, are contemplated herein.

[0010] Fig. 1-5 show various aspects of an internal combustion engine 10. The internal combustion engine 10 includes at least one cylinder 12 including a combustion chamber 14. The internal combustion engine 10 includes at least one port injector 70, 80 operable to inject a gaseous fuel for delivery to the combustion chamber 14. An intake manifold 30 is configured to provide a charge flow 20 to the combustion chamber 14. The intake manifold 30 includes a first inlet port 32 connected to a first port outlet 34. The first inlet port 32 is configured to introduce charge flow 20 into the combustion chamber 14 through the first port outlet 34. The intake manifold 30 includes a second inlet port 36 connected to a second port outlet 38. The second inlet port 36 is configured to introduce charge flow 20 into the combustion chamber 14 through the second port outlet 38.The intake manifold 30 includes at least one fuel passage 100, 100' connecting the at least one port injector 70, 80 to each of the first inlet port 32 and the second inlet port 36 upstream of the first port outlet 34 and the second port outlet 38. The at least one fuel passage 100, 100' is configured to distribute gaseous fuel injected by the at least one port injector 70, 80 to each of the first inlet port 32 and the second inlet port 36 for delivery to the combustion chamber 14 through each of the first and second inlet port outlets 34, 38.

[0011] Additionally disclosed is an intake manifold 30 for distributing a charge flow 20 to the internal combustion engine 10. The intake manifold 30 includes a first inlet port 32 for receiving a first portion of the charge flow 20. The first inlet port 32 is configured to provide the first portion of the charge flow 20 to a combustion chamber 14 of the internal combustion engine 10. The intake manifold 30 includes a second inlet port 36 for receiving a second portion of the charge flow 20. The second inlet port 36 is configured to provide the second portion of the charge flow to the combustion chamber 14. The intake manifold 30 includes at least one port injector inlet 112, 114. The intake manifold 30 includes at least one fuel passage 100, 100' connecting the at least one port injector inlet 112, 114 to each of the first inlet port 32 and the second inlet port 36.

[0012] With reference to Fig. 1, the internal combustion engine 10 includes a plurality of cylinders 12. Each of the cylinders 12 includes a combustion chamber 14. The internal combustion engine 10 also includes an inlet 16 and an outlet 18 connected to each combustion chamber 14 of the cylinders 12. The inlet 16 provides a charge flow 20 to the combustion chambers 14, and the outlet 18 provides a path for the exhaust flow 22 to be expelled from the combustion chambers 14.

[0013] The engine 10 further includes an intake manifold 30 extending along one or more of the cylinders 12. The intake manifold 30 and / or the intake ports 32, 36 may be connected to and / or form part of a cylinder head 26. The intake manifold 30 distributes the charge flow 20 to the combustion chambers 14 via a plurality of intake ports, as explained below. An exhaust manifold 28 collects the exhaust output from combustion in the combustion chambers 14 of each of the cylinders 12 and provides the exhaust flow 22 to the exhaust 18.

[0014] The engine 10 may be any type of engine and, in a specific embodiment, is an internal combustion engine including a number of cylinders 12, each housing a piston 24. In one embodiment, the engine 10 is powered by gaseous fuel, such as natural gas, propane, hydrogen, etc. A source of gaseous fuel 50 may be connected to a manifold 52 that distributes the gaseous fuel to a pair of port injectors 70, 80 associated with a pair of intake ports 32, 36 for each of the one or more cylinders 12.

[0015] As explained below, each of the two port injectors 70, 80 receives gaseous fuel from the fuel source 50 via a manifold 52. The port injectors 70, 80 are operable to provide controlled injection of gaseous fuel into the intake ports 32, 36 in response to fuel delivery commands from a controller (not shown) that are responsive to providing the desired engine output. It is contemplated that any type of port injector 70, 80 may be used as the port injectors. Additionally, embodiments are contemplated in which only one port injector 70 or 80 is provided and only one port injector 70, 80 is connected to each inlet port 32, 36 with the fuel passage 100, 100'.

[0016] In the illustrated embodiment, the engine 10 includes six cylinders 12 connected to the intake manifold 30 and the exhaust manifold 28 via the cylinder head 26. However, any number of cylinders 12 that can be used for an engine 10 is contemplated. The engine 10 may be an in-line engine with a single cylinder bank, as shown in the illustrated embodiment, or another configuration including V-shaped cylinder arrangements, a W-engine, or any engine arrangement having one or more cylinders 12. It is contemplated that the engine 10 may be provided as part of a powertrain for a vehicle (not shown), however, other applications are also contemplated, such as generator sets, equipment, and marine applications.

[0017] With further reference to Fig. 2-3, each cylinder 12 includes a combustion chamber 14 and a piston 15 movably disposed within the combustion chamber 14. Each cylinder 12 may also include a spark plug 17, intake valves 60, 62, and one or more exhaust valves (not shown). Each cylinder 12 may include other components and features not disclosed herein. In the illustrated embodiment, the intake valve 60 extends into the first intake port 32, and the intake valve 62 extends into the second intake port 36.

[0018] In the illustrated embodiment of Fig. 2-3, the intake manifold 30 includes at least one first intake port 32 paired with a corresponding second intake port 36. Each cylinder 12 of the engine 10 may include paired first and second intake ports 32, 36. The paired first and second intake ports 32, 36 are each fluidly connected to one of the plurality of cylinders 12 to provide a charge flow 20 to the combustion chambers 14. Additionally, the first and second intake ports 32, 36 of each cylinder 12 are interconnected with at least one fuel passage 100 or at least one fuel passage 100' ( Fig. 5).

[0019] The first intake port 32, the second intake port 36, and / or the fuel passage 100, 100' may be formed by casting, drilling, machining, assembling, or other forming techniques for the intake manifold 30 and / or the cylinder head 26. The intake manifold 30 may be comprised of a single, unitary body sized to extend along all cylinders 12 of the engine 10, divided into two or more portions spanning one or more cylinders 12, or assembled from multiple components. Additionally, the intake manifold 30 may include other features not shown in the illustrated embodiments, such as passages, bores, and other ports for sensors, fasteners, and the like.

[0020] Each of the first intake ports 32 includes a respective first port outlet 34, and each of the second intake ports 36 includes a respective second port outlet 38. The first port outlet 34 and the second port outlet 38 allow the charge flow 20 into the combustion chamber 14 of the corresponding cylinder 12 when the intake valves 60, 62 are lifted from their respective valve seats 64, 66. For example, each cylinder 12 includes two intake valves 60, 62 that are opened and closed by a valve opening mechanism (not shown) via a camshaft (not shown). Opening the valve(s) 60, 62 allows charge flow 20 to be admitted into the combustion chamber 14 of the respective cylinder 12 via the port outlets 34, 38.

[0021] The intake manifold 30 further includes a first port injector 70 and a second port injector 80 mounted thereon. The port injectors 70, 80 are each connected to the first inlet port 32 and the second inlet port 36 with at least one fuel passage 100. In the illustrated embodiment of Fig. 2-4, the at least one fuel passage 100 includes a first fuel passage 102 and a second fuel passage 104. The first and second fuel passages 100, 102 intersect to form an X-shape, although other linear and / or non-linear shapes are contemplated and not excluded. For example, embodiments with a single port fuel injector may have an inverted Y-shape.

[0022] The first fuel passage 102 includes a first port injector inlet 112, and the second fuel passage 104 includes a second port injector inlet 114. The first port injector 70 is fluidly connected to the first fuel passage 102 at the first port injector inlet 112, and the second port injector 80 is fluidly connected to the second fuel passage 104 at the second port injector inlet 114. The first fuel passage 102 further includes a first gaseous fuel outlet 116 connected to the second inlet port 36, and the second fuel passage 104 includes a second gaseous fuel outlet 118 connected to the first inlet port 32.

[0023] The intersecting fuel channels 102, 104 allow gaseous fuel from both intake manifold injectors 70, 80 to be distributed to both the first inlet port 32 and the second inlet port 36, as shown in Fig. 2. When only one intake manifold injector 70, 80 is used to inject fuel, such as during low engine load conditions, fuel injected by the active one of the intake manifold injectors 70, 80 is distributed evenly or substantially evenly between the first and second inlet ports 32, 36. For example, in Fig. 4 Fuel is injected only from the intake port 70 into the connected portion of the first fuel passage 102. The connection of the first fuel passage 102 to the second fuel passage 104 distributes some of the injected fuel from the first fuel passage 102 and into the second fuel passage 104. As a result, injected fuel from the one port injector 70 is distributed to each of the first and second intake ports 32, 36. A similar result is obtained when fuel is injected only from the second port injector 80 into the second fuel passage 104.

[0024] In one embodiment, the first fuel passage 102 between the first port injector inlet 112 and the first gaseous fuel outlet 116 has a cylindrical shape. The second fuel passage 104 between the second port injector inlet 114 and the second gaseous fuel outlet 118 also has a cylindrical shape. Other embodiments contemplate other shapes for one or both of the first fuel passage 102 and the second fuel passage 104. For example, the fuel passage shapes may be smooth, non-uniform, tapered, conical, etc.

[0025] In one embodiment, the first fuel passage 102 and the second fuel passage 104 are formed by drilling through the intake manifold material used to cast the first intake port 32 and the second intake port 36. Other techniques may also be used to form the first fuel passage 102 and the second fuel passage 104, including machining, casting, printing, or otherwise forming the first fuel passage 102 and the second fuel passage 104.

[0026] In Fig.5 shows another embodiment of the fuel passage 100'. The fuel passage 100' includes a distribution chamber 106 that extends between and fluidly connects the first port injector inlet 112, the second port injector inlet 114, the first gaseous fuel outlet 116, and the second gaseous fuel outlet 118. In one embodiment, the distribution chamber 106 includes a first end 120 between the port injector inlets 112, 114 and a second end 122 between the gaseous fuel outlets 116, 118. The distribution chamber 106 also includes a first side 124 extending between the first port injector inlet 112 and the second gaseous fuel outlet 118, and a second side 126 extending between the second port injector inlet 114 and the first gaseous fuel outlet 116.

[0027] In the illustrated embodiment, the distribution chamber 106 expands from the port injector inlets 112, 114 to the gaseous fuel outlets 116, 118. Other embodiments contemplate other shapes and configurations for the distribution chamber 106, as long as gaseous fuel from at least one port injector 70, 80 is distributed to each of the intake ports 32, 36.

[0028] In operation, fuel injected from either the first port injector 70 or the second port injector 80 is received in the distribution chamber 106 and distributed evenly or substantially evenly between the first gaseous fuel outlet 116 and the second gaseous fuel outlet 118. Consequently, fuel injected from a single port injector 70, 80 is distributed via the distribution chamber 106 to both the first inlet port 32 and the second inlet port 36.

[0029] In one embodiment, the fuel passage 100' is formed by molding within the intake manifold material used to mold the first intake port 32 and the second intake port 36. Other techniques for forming the fuel passage 100' may also be used, including machining, printing, or otherwise forming the first fuel passage 100' and its distribution chamber 106.

[0030] It is contemplated that the distribution chamber 106 does not contain the charge flow 20, but only distributes gaseous fuel to the intake ports 32, 36. In one embodiment, the first and second fuel passages 102, 104 do not contain the charge flow 20 and only distribute gaseous fuel to the intake ports 32, 36. The positions of the port injectors 70, 80 and the at least one fuel passage 100, 100' allow gaseous fuel to be provided to each intake port 32, 36 without mixing with the charge flow 20.

[0031] Many aspects of the present disclosure are provided. For example, one aspect is directed to an internal combustion engine including at least one cylinder including a combustion chamber, at least one port injector operable to inject a gaseous fuel for delivery to the combustion chamber, and an intake manifold configured to provide a charge flow to the combustion chamber. The intake manifold includes a first inlet port connected to a first port output and a second inlet port connected to a second port output. The first inlet port is configured to introduce charge flow into the combustion chamber through the first port output, and the second inlet port is configured to introduce charge flow fuel into the combustion chamber through the second port output.At least one fuel passage connects the at least one port injector to each of the first inlet port and the second inlet port upstream of the first port outlet and the second port outlet. The at least one fuel passage is configured to distribute gaseous fuel injected by the at least one port injector to each of the first inlet port and the second inlet port for delivery to the combustion chamber through each of the first and second port outlets.

[0032] In one embodiment, the at least one port injector includes a first port injector and a second port injector, and the at least one fuel passage connects each of the first and second port injectors to each of the first and second inlet ports.

[0033] In one embodiment, the at least one fuel passage includes a first port injector inlet connected to the first port injector, a second port injector inlet connected to the second port injector, a first gaseous fuel outlet connected to the first inlet port, and a second gaseous fuel outlet connected to the second inlet port.

[0034] In one embodiment, the at least one fuel passage includes a distribution chamber within the intake manifold head fluidly connecting the first and second port injector inlets to the first and second gaseous fuel outlets.

[0035] In one embodiment, the distribution chamber includes a first end extending between the first and second port injector inlets, a second end extending between the first and second gaseous fuel outlets, a first side extending from the first port injector inlet to the first gaseous fuel outlet, and a second side extending from the second port injector inlet to the second gaseous fuel outlet.

[0036] In one embodiment, the at least one fuel passage includes a first fuel passage extending from the first port injector inlet to the second gaseous fuel outlet, and a second fuel passage extending from the second port injector inlet to the first gaseous fuel outlet. The second fuel passage intersects the first fuel passage between the first port injector inlet and the second gaseous fuel outlet.

[0037] In one embodiment, the first fuel passage and the second fuel passage form an X-shape between the first and second port injector inlets and the first and second gaseous fuel outlets.

[0038] In one embodiment, the at least one fuel passage is configured to distribute gaseous fuel injected simultaneously from the first port injector and the second port injector to each of the first inlet port and the second inlet port.

[0039] In one embodiment, the at least one fuel passage does not include boost flow. In one embodiment, the at least one fuel passage is cast into the intake manifold. In one embodiment, the at least one fuel passage includes a first fuel passage and a second fuel passage drilled through the intake manifold in an intersecting relationship.

[0040] According to another aspect of the invention, an intake manifold is provided for distributing a charge flow to an internal combustion engine. The intake manifold includes a first inlet port for receiving a first portion of the charge flow and a second inlet port for receiving a second portion of the charge flow. The first inlet port is configured to provide the first portion of the charge flow to a combustion chamber of the internal combustion engine, and the second inlet port is configured to provide the second portion of the charge flow to the combustion chamber of the internal combustion engine. The intake manifold also includes at least one port injector inlet and at least one fuel passage connecting the at least one port injector inlet to each of the first inlet port and the second inlet port.

[0041] In one embodiment, the at least one port injector inlet includes a first port injector inlet and a second port injector inlet, and the at least one fuel passage connects the first port injector inlet to the first and second inlet ports and the second port injector inlet to the first and second inlet ports.

[0042] In one embodiment, the at least one fuel passage of the cylinder head includes a first fuel passage extending from the first port injector inlet to the second intake port and a second fuel passage extending from the second port injector to the first intake port.

[0043] In one embodiment, the first fuel passage crosses the second fuel passage between the second port injector inlet and the first inlet port.

[0044] In one embodiment, the first fuel passage from the first port injector inlet to the second inlet port is cylindrically shaped and the second fuel passage from the second port injector inlet to the first inlet port is cylindrically shaped.

[0045] In one embodiment, the intake manifold includes a fuel rail extending between the first port injector inlet and the second port injector inlet.

[0046] In one embodiment, the at least one fuel passage includes a distribution chamber fluidly connecting the at least one port injector inlet to the first and second inlet ports.

[0047] In one embodiment, the distribution chamber includes a first outlet connected to the first inlet port and a second outlet connected to the second inlet port. In one embodiment, the distribution chamber extends from the at least one port injector inlet to the first and second outlets.

[0048] While the invention has been illustrated and described in detail in the drawings and the foregoing description, it is to be considered as illustrative and not restrictive, and it is to be understood that only certain exemplary embodiments have been shown and described. Those skilled in the art will recognize that many modifications are possible in the exemplary embodiments without materially departing from this invention. Accordingly, it is intended that all such modifications be included within the scope of this disclosure as defined in the claims. In reading the claims, it is intended that the use of words such as "a," "an," "at least one," or "at least one part / portion" is not intended to limit the claim to only one subject matter, unless the claim expressly states otherwise.When the phrase "at least a part / section" and / or "a part / section" is used, the subject matter may include a part / section and / or the entire subject matter, unless expressly stated otherwise. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 386,253

[0001]

Claims

[1] Internal combustion engine, the internal combustion engine comprising: at least one cylinder containing a combustion chamber; at least one port injector operable to inject a gaseous fuel for delivery to the combustion chamber; an intake manifold configured to provide charge flow to the combustion chamber, the intake manifold including: a first inlet port connected to a first port outlet, the first inlet port configured to introduce charge flow into the combustion chamber through the first port outlet; a second inlet port connected to a second port outlet, the second inlet port configured to introduce fuel charge flow into the combustion chamber through the second port outlet; and at least one fuel passage connecting the at least one port injector to each of the first inlet port and the second inlet port upstream of the first port outlet and the second port outlet, the at least one fuel passage configured to distribute gaseous fuel injected by the at least one port injector to each of the first inlet port and the second inlet port for delivery to the combustion chamber through each of the first and second port outlets. [2] The internal combustion engine of claim 1, wherein the at least one port injector includes a first port injector and a second port injector, and the at least one fuel passage connects each of the first and second port injectors to each of the first and second intake ports. [3] Internal combustion engine according to claim 2, wherein the at least one fuel channel includes: a first port injector input connected to the first port injector; a second port injector input connected to the second port injector; a first gaseous fuel outlet connected to the first inlet port; and a second gaseous fuel outlet connected to the second inlet port. [4] The internal combustion engine of claim 3, wherein the at least one fuel passage includes a distribution chamber within the intake manifold head fluidly connecting the first and second port injector inlets to the first and second gaseous fuel outlets. [5] An internal combustion engine according to claim 4, wherein the distribution chamber comprises: a first end extending between the first and second port injector inlets; a second end extending between the first and second gaseous fuel outlets; a first side extending from the first port injector inlet to the first gaseous fuel outlet; and a second side extending from the second port injector inlet to the second gaseous fuel outlet. [6] Internal combustion engine according to claim 3, wherein the at least one fuel channel includes: a first fuel passage extending from the first port injector inlet to the second gaseous fuel outlet; and a second fuel passage extending from the second port injector inlet to the first gaseous fuel outlet, the second fuel passage crossing the first fuel passage between the first port injector inlet and the second gaseous fuel outlet. [7] An internal combustion engine according to claim 6, wherein the first fuel passage and the second fuel passage form an X-shape between the first and second port injector inlets and the first and second gaseous fuel outlets. [8] The internal combustion engine of claim 2, wherein the at least one fuel passage is configured to distribute gaseous fuel injected simultaneously from the first port injector and the second port injector to each of the first intake port and the second intake port. [9] Internal combustion engine according to claim 1, wherein the at least one fuel channel does not include a charge flow. [10] The internal combustion engine of claim 1, wherein the at least one fuel passage is cast into the intake manifold. [11] The internal combustion engine of claim 1, wherein the at least one fuel passage includes a first fuel passage and a second fuel passage drilled through the intake manifold in an intersecting relationship. [12] Intake manifold for distributing a charge flow to an internal combustion engine, the intake manifold comprising: a first inlet port for receiving a first portion of the charge flow, the first inlet port configured to provide the first portion of the charge flow to a combustion chamber of the internal combustion engine; a second inlet port for receiving a second portion of the charge flow, the second inlet port configured to provide the second portion of the charge flow to the combustion chamber of the internal combustion engine; at least one intake manifold injector input; and at least one fuel passage connecting the at least one port injector inlet to each of the first inlet port and the second inlet port. [13] The intake manifold of claim 12, wherein the at least one port injector inlet includes a first port injector inlet and a second port injector inlet, and the at least one fuel passage connects the first port injector inlet to the first and second inlet ports and the second port injector inlet to the first and second inlet ports. [14] The intake manifold of claim 13, wherein the at least one fuel passage of the cylinder head includes a first fuel passage extending from the first port injector inlet to the second intake port and a second fuel passage extending from the second port injector to the first intake port. [15] The intake manifold of claim 14, wherein the first fuel passage crosses the second fuel passage between the second port injector inlet and the first inlet port. [16] Intake manifold according to claim 14, wherein: the first fuel passage from the first port injector inlet to the second inlet port is cylindrically shaped; and the second fuel channel from the second intake manifold injector inlet to the first inlet port is cylindrically shaped. [17] The intake manifold of claim 13, further comprising a fuel rail extending between the first port injector inlet and the second port injector inlet. [18] The intake manifold of claim 12, wherein the at least one fuel passage includes a distribution chamber fluidly connecting the at least one port injector input to the first and second inlet ports. [19] The intake manifold of claim 18, wherein the distribution chamber includes a first outlet connected to the first inlet port and a second outlet connected to the second inlet port. [20] The intake manifold of claim 19, wherein the distribution chamber extends from the at least one port injector inlet to the first and second outlets.

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