Methods and systems are provided for user controlled engine revving. In one example, the engine may be revved to a peak speed according to a target revving sequence in response to a user-initiated command. A revving sound may be provided in response to an input device, without demanding manual depression of an accelerator pedal.

A variable valve for a muffler may include an actuator; a valve tube having an inlet into which exhaust gas is flowed, and a first outlet and a second outlet into which the exhaust gas is discharged, and installed in a middle of a tail pipe into which the exhaust gas is discharged from a muffler; and a valve body in a ball shape rotatably installed in the valve tube, and rotatable by a rotational force delivered from the actuator to block the inlet, or to communicate the inlet with a selected one of the first outlet and the second outlet according to a rotated state of the valve body.

An apparatus and method are provided for a drone elimination muffler to attenuate drone exhibited by engine exhaust systems. The drone elimination muffler comprises a hollow canister having a length and a diameter, and a tuned port comprising a first end connected to the canister and a second end connected to the exhaust system. The canister operates in concert with the tuned port as a dampener configured to substantially attenuate exhaust drone, or resonance, at one or more frequencies of engine operation. A valve is configured to switch the drone elimination muffler between a closed state in which the exhaust system operates without acoustic influence due to the drone elimination muffler, and an open state in which the drone elimination muffler directly influences the acoustic properties of the exhaust system.

A motor-driven throttle valve for an exhaust duct and having: a tubular duct, which is designed so that exhaust gases can flow through it; a throttle shutter, which is arranged inside the tubular duct and is mounted so as to rotate around a rotation axis; a first shaft, which is mounted so as to rotate around the rotation axis and supports the throttle shutter; an electric actuator, which is provided with a second shaft and is designed to rotate the shaft around the rotation axis; a support bearing, which supports the shaft in a through manner and is arranged on the outside of the tubular duct; and a spring, which applies to the shaft an elastic force, which axially pushes the shaft and, at the same time, is configured to transmit a rotary motion around the rotation axis from the second shaft of the electric actuator to the first shaft supporting the throttle shutter.

The preferred invention is directed to a controller for a vehicle exhaust valve. The controller comprises a vehicle interface for determining a live value for an operating parameter of a vehicle, a recording module being configured to, upon activation, instantaneously record the live value of the operating parameter, and a programming module for determining a value range based on the recorded live value and allowing a desired position of the valve to be set such that during operation, the control system automatically moves the valve to the desired position when the operating parameter is within the value range.

Methods and systems are provided for user controlled engine revving. In one example, the engine may be revved to a peak speed according to a target revving sequence in response to a user-initiated command. A revving sound may be provided in response to an input device, without demanding manual depression of an accelerator pedal.

Systems and methods for operating an engine that includes an exhaust tuning valve in its exhaust system are described. In one example, a position of the exhaust tuning valve may be adjusted to reduce a possibility of the exhaust tuning valve becoming stuck due to freezing water. In particular, the exhaust tuning valve may be cycled as ambient temperature approaches a temperature at which water freezes.

An engine exhaust system includes a catalytic converter, an exhaust conduit connected upstream of the catalytic converter, and an oxygen sensor extending into the exhaust conduit at a first axial position of the exhaust conduit. A valve is located within the exhaust conduit at the first axial position. The valve includes a movable throttle plate having a bypass notch formed on a periphery of the plate. The valve has an open position, and a closed position in which the bypass notch is placed adjacent to the oxygen sensor to guide exhaust over the oxygen sensor.

A motor-driven throttle valve for an exhaust duct and having: a tubular duct, which is designed so that exhaust gases can flow through it; a throttle shutter, which is arranged inside the tubular duct and is mounted so as to rotate around a rotation axis; a first shaft, which is mounted so as to rotate around the rotation axis and supports the throttle shutter; an electric actuator, which is provided with a second shaft and is designed to rotate the shaft around the rotation axis; a support bearing, which supports the shaft in a through manner and is arranged on the outside of the tubular duct; and a spring, which applies to the shaft an elastic force, which axially pushes the shaft and, at the same time, is configured to transmit a rotary motion around the rotation axis from the second shaft of the electric actuator to the first shaft supporting the throttle shutter.

Methods and systems are provided for adjusting a position of an exhaust valve that regulates engine exhaust noise. In one example, the position of the exhaust valve is adjusted according to a distance between a first vehicle and a second vehicle. The exhaust valve may be adjusted to reduce an exhaust noise level when the distance between the first vehicle and the second vehicle is less than a threshold distance.