A good Glasspack muffler is one of the best mufflers present in the automotive world nowadays. The design is simple. The exhaust passes through the center of the pipe and the padding around the exhaust pipe muffles the vibration and sound of the engine. But this variety of muffler does have its advantages and disadvantages too.
Advantages of Glasspack Mufflers
Glass pack mufflers work on the simple principle that all the sound generated by the car engine is passed through a sound absorbing material before it is released. This means very little sound is allowed to escape the muffler, and the sound blanketing capacity of the muffler is excellent. Several people commonly refer to the Glasspack Muffler as the Cherry Bomb Muffler due to its really great sound muffling abilities. These mufflers are also much better than ordinary mufflers, as they do not allow the sound to resonate back into the engine. This usually happens in ordinary engines, causing them to dissipate without damaging human ears. The loud sound of the engine is negated by the same loud sound produced by an ordinary muffler. But this creates negative pressure on the engine. The glasspack muffler reduces the pressure on the engine by dissipating the pressure of the loud sound waves out through a sleeve of glass particles. Another advantage is that they are quite cheap at about $20-$100.
Disadvantages of Glasspack Mufflers
Glasspack Mufflers don't really work on every kind of car. Another problem is that as they do get old, they start to sound really bad. They require regular care too.
But on the whole Glasspack Mufflers are pretty good. They offer value for money and have a good capability for absorbing sound. But make sure you check with the garage before you get them installed.