Yeah, definitely, that Y pipe would divert into the resonator for a "silent" system. Once that valve opened up, the vast majority of sound would really just come from the side without a resonator. Also, probably a simple solenoid controlled valve is what it seems... especially if it's electronic.
The only questions I have toward dual-mode exhausts is that:
- More moving parts usually aren't a good thing.
- Increased backpressure from a closed valve, although it's silent and meant for "grandma" driving, it still doesn't look too good.
- All the sound just comes from one muffler end, really. Not too much of a bother but a balanced sound is better to me.
- No symmetry under the car... "hey why doesn't that left side have a block in it"
I'm just whining really but I saw the Sacalm exhaust and like the other people that saw it, I kinda went "wtf" at the sealed center piping and the interestingly shaped resonator ends. And what is that thing, a heat shield?