I plan on modifying my R/T slightly with the Flowmaster 40 series muffler. What exactly will this do? And how do I increase the classic sound desired from this modern day muscle car? The company suggested removing the rear resonators which would cut out the muffling of the exhaust but from what I've seen on youtube nothing really increases the growling sound of the engine.

 

Here's a Youtube video of my Challenger with American Thunder Flowmaster (Super 40 I think) mufflers installed.