Some states require a muffler to prevent excessive noise, while others require an exhaust system, and some states require a muffler or exhaust system and allow drivers to choose between the two.
Modifying a car muffler to make it louder is illegal in Washington, though Washington State Patrol citation data doesn't show many tickets written for the alterations. (iStock.com) Tim Halloran ...
Can you drive a car or motorcycle without a muffler in ... by enabling the driver to determine whether the exhaust bypasses or exits the muffler as usual. This can be controlled by the driver ...