To keep the heat on the down-low, I’d like to keep my stock exhaust and get an e-cutout for any track days my car might be seeing (unlikely).

A cutout is a device which is welded right after the down-pipe on an exhaust system. It has a flange that opens via an electronic solenoid (activated in the car) and releases the exhaust gases after the down-pipe instead of travelling through the rest of the exhaust system (b-piping, catalytic converter and muffler). A cutout slightly improves a motor’s output.