Originally Posted by
markk
How you going to open the butterfly?
On my Escort rally car it has twin side exit. One has a silencer and a catalyst the other has nothing. My butterfly valve is controlled by the ecu on boost pressure. Below 0.5bar everything goes quiet and through the cat. Above that through both.
You can get electric solenoid operated exhaust valves.
I too have thought about them
Cheers Paul