What does the muffler do in a classic VW bug?

Answer 1

Well it provides the right back pressure for the car to run well. It muffles the sound of the exhaust as well as creates an outlet for the exhaust gasses to escape. Cars don't run well on exhaust fumes so you need to get them out of the head and away from the intake as efficiently as possible. It also (on later models, Dual Ports) helps to heat the intake. In winter time your intake will freeze right below the carb this is because of the cold temps outside as well as very cold fuel hitting very cold metal. There are two small pipes that come off the intake(on Dual Port motors) that go down and meet with the exhaust, these are called the heat risers. These are what heat the intake.