A vehicle includes an engine configured to generate power and noise. The vehicle includes a transmission configured to operate in a first gear corresponding to a first gear ratio and a second gear corresponding to a second gear ratio. The second gear ratio is less than the first gear ratio. The vehicle also includes a noise reduction device coupled to the engine and configured to operate in a first state to reduce the noise of the engine to a first volume and a second state to reduce the noise of the engine to a second volume that is greater than the first volume. The vehicle also includes an electronic control unit (ECU) coupled to the engine, the transmission and the noise reduction device and configured to control the noise reduction device to switch to the second state when the transmission shifts from the second gear to the first gear.

A vehicle includes an engine configured to generate power and noise. The vehicle includes a transmission configured to operate in a first gear corresponding to a first gear ratio and a second gear corresponding to a second gear ratio. The second gear ratio is less than the first gear ratio. The vehicle also includes a noise reduction device coupled to the engine and configured to operate in a first state to reduce the noise of the engine to a first volume and a second state to reduce the noise of the engine to a second volume that is greater than the first volume. The vehicle also includes an electronic control unit (ECU) coupled to the engine, the transmission and the noise reduction device and configured to control the noise reduction device to switch to the second state when the transmission shifts from the second gear to the first gear.

A silencer for noise reduction at an internal combustion engine is disclosed. The silencer comprises an input opening, an output opening, at least one chamber, and at least one partition configured to be inserted into and removed from the at least one chamber to convert the silencer to a collector.

An embodiment of an exhaust handling system for a marine vessel includes a cap connected to a top end portion of an exhaust stack of the marine vessel to form an enclosure at least partially surrounding an outlet of an exhaust pipe extending through the exhaust stack. In addition, the exhaust handling system includes a collection pipe in fluid communication with the cap such that the collection pipe is to receive exhaust from the enclosure, and a coupling connected to the collection pipe that is to connect to an exhaust cleaning assembly. The exhaust cleaning system includes a tank to receive the exhaust. The cap at least partially defines a first flow path for the exhaust that extends from the enclosure to the atmosphere. The collection pipe at least partially defines a second flow path for the exhaust that extends from the enclosure to the coupling via the collection pipe.

A muffler assembly for a vehicle exhaust system including a muffler that has a primary muffler conduit with a primary resonator, a secondary muffler conduit with a secondary resonator, and a valve that directs exhaust flow through both the primary and secondary muffler conduits or primarily through the secondary muffler conduit depending on the position of the valve. The muffler provides a first level of sound attenuation when the valve is in an open position and a second level of sound attenuation when the valve is in a closed position. The second level of sound attenuation is greater than the first level of sound attenuation and therefore the muffler provides a louder exhaust sound when the valve is in the open position and a quieter exhaust sound when the valve is in the closed position.

An embodiment of an exhaust handling system for a marine vessel includes a cap connected to a top end portion of an exhaust stack of the marine vessel to form an enclosure at least partially surrounding an outlet of an exhaust pipe extending through the exhaust stack. In addition, the exhaust handling system includes a collection pipe in fluid communication with the cap such that the collection pipe is to receive exhaust from the enclosure, and a coupling connected to the collection pipe that is to connect to an exhaust cleaning assembly. The exhaust cleaning system includes a tank to receive the exhaust. The cap at least partially defines a first flow path for the exhaust that extends from the enclosure to the atmosphere. The collection pipe at least partially defines a second flow path for the exhaust that extends from the enclosure to the coupling via the collection pipe.

A silencer for noise reduction at an internal combustion engine is disclosed. The silencer comprises an input opening, an output opening, at least one chamber, and at least one partition configured to be inserted into and removed from the at least one chamber to convert the silencer to a collector.