Anybody ever try this on an aftermarket exhaust for an even more aggressive sound? Rather than going with race cats, headers or x-pipes to complement the exhaust. Just curious.

 

An after market exhaust system, cats and headers esp, is designed and tested to facilitate the flow of gasses from the engine in an effort to increase power output. Some are more successful than others. The purpose is not to make more noise. Ne1 who would pay upwards of 4-5000$ and then screw up the manufacturers design via a "hack" should donate their money to my favorite charity instead. (Details upon request). In the meantime, you can just unbolt your headers for the sound others love to hear.