[Viper]

I have no cats or rear muffler. Good sound but evil resonance at times. Bought a pair of Sony noise cancellation headsets and they work great. Actually can hear things going on while driving that I never heard before.

Downside, you wearing headphones while driving. Uber dork points.

 

[PRVT JET]

That's also illegal in some states or all states. I know people that wear ear plugs when they drive.

 

[Gerald]

Try keeping a full tank of gas in the car, that usually helps.

G

 

[GTS Dean]

An x-pipe does a great job of minimizing the drone.