Exhaust system Law in the United States and other countries to not have a catalytic converter. Converters may not be removed from a vehicle that is used only for "off-road" driving in the United States. The main purpose of a catalytic converter on an automobile is to reduce harmful emissions of hydrocarbons, carbon monoxide and nitrogen oxides into the atmosphere. They work by transforming the polluted exhaust components into water and carbon dioxide. Cat-back (also cat back and catback) refers to the portion of the exhaust system from the outlet of the catalytic converter to the final vent to open air. This
Aftermarket exhaust parts but are very effective at reducing the sound levels. The piping that connects all of the individual components of the exhaust system is called the exhaust pipe. Contrary to popular belief, the larger diameter exhaust pipe is not always better. If the pipe is too large, the scavenging effect will suffer at low rpm, resulting in loss of torque and driveability. Running a pipe that is too large may also decrease a car's ground clearance, increasing the risk of the exhaust being damaged when the car moves over an uneven surface. While it was common for the stock or factory