Glasspacks:

Dynomax Ultra Flows are a glasspack muffler. You can get them to fit in place of your factory mufflers. They probably won't be as loud as a Cherry Bomb type glasspack, but they sound better IMO.
 
when i bought my car it had a o/r h glasspacks and tails and it is the most annoying loud stupid sound....i spend 330 bucks for a cat back i absolutly could not stand my car with glasspacks just figured i would let you know. i got a 4 month old and i wouldn't want to load him up in that car he would never be able to sleep