Check out the complete course at https://www.howacarworks.com/video-course This episode has everything you need to know about the exhaust muffler, or in British English, the silencer. We cover what it does, why it's needed, and then chop a muffler up and see what's inside. I also talk about exhaust back pressure and the differences between turbo muffler, absorption or straight-through mufflers, and finally we look at chambered designs. 00:00 Why is a muffler needed 00:58 Engine noise 02:16 Acoustic tuning 04:05 Different engines. Different sounds. 05:06 Dissecting a muffler 09:36 What's inside 10:03 Difference between noise and gas movement 11:36 Absorption and Reflection 15:11 Straight-through muffler 15:39 Turbo mufflers 15:57 Exhaust back-pressure 21:42 Why mufflers corrode so quickly 23:27 Chambered muffler 24:15 Active exhaust systems