Using a Hobbs switch to control a 3 way switch

[Pushit2.0]

I think in this case you might want to plan 3 seconds in advance for your cut out. Or find a way to have a flapper system that opens under higher exhaust pressure, kind of like a stock evo muffler. Most cut outs are DC motors and only need ~3 seconds to open then a polarity switch and ~3 seconds to close, so Ryan your controller would work.

~John