Semi-Active Muffler Valve
| ITEM | DESCRIPTION |
|---|---|
| 1 | Outer case |
| 2 | Overpipe |
| 3 | Valve cage |
| 4 | Semi-active muffler valve assembly |
A semi-active muffler valve is located in the rear of each rear silencer. The valve comprises a valve head, a valve shaft, a shaft guide, a housing shell, a membrane and a spring. The valve head is connected to the membrane by the valve shaft which is located within the shaft guide. The valve shaft is attached to the membrane with a pin. The membrane is located inside the housing shell and is held in position by the spring.
The valve head is located in and seals against the over pipe. When the exhaust gas pressure increases and overcomes the spring pressure, the valve head is lifted and the gasses by-pass the valve and are expelled though slots in the valve cage into the rear chamber and into the outlet pipe.
When the semi-active muffler valve is closed the exhaust gasses are expelled from the inlet tube through the perforations. The exhaust gasses then pass through perforations in the outlet pipe and are expelled from the silencer via the single outlet pipe and 2 polished stainless steel finishers.
When the semi-active muffler valve is open, the exhaust gasses are released into the rear chamber. The exhaust gasses then pass directly into the open end of the outlet pipe and are expelled from the silencer via the outlet pipe and the 2 polished stainless steel finishers. With the valve open, the gasses reduce through the baffle plates and tube perforations giving the exhaust note a more 'sporty' sound.