The problem with exhaust systems is that they're either loud or quiet. And sometimes you want one and not the other. Meet the first active exhaust for the Miata! They're popping up on high end cars all over the place.
At idle and light throttle, the exhaust stream is routed through an effective muffler that keeps the sound levels low. Very comfortable and neighbourhood-friendly.
But when you dip deeper into the throttle pedal, a butterfly opens to allow the exhaust to bypass the muffler completely. This cuts down on restriction and you can hear the car respond to your extra enthusiasm. When you want it loud, it's loud. Never obnoxiously so, but sporty.
We also have a CAN integration package that allows you to change the behavior of the exhaust on the fly by simply twisting a dial. You can change from always loud to always quiet or set the percentage of throttle needed to open the bypass.
We cannot give a specific decibel rating for this exhaust, as that depends on the measuring technique as well as other modifications on the car. If you are competing in a noise-sensitive facility and are having trouble with noise levels, it's possible to change the muffler over to the "always quiet" mode quickly and easily. That will drop sound levels to just a bit over the stock muffler.
*Due to the design and operation of the butterfly valve used in the Hush-O-Matic muffler, the valve may experience a slight vibrational noise at the point of closure. This typically happens when applying a light throttle, however in most cases the there is little to no noticeable effects. The CAN control system eliminates the chance of this noise.