Why Do Some Vehicles Have 2 Exhaust Pipe

Ever notice how some vehicles have two exhaust pipes? All vehicles that feature an Internal Combustion Engine (ICE) require at least one exhaust pipe. Exhaust pipes are metal pipes that release exhaust gases produced by engines. Engines will burn gas and air while creating exhaust gases as a byproduct. These exhaust gases will travel through the exhaust system before being expelled from the exhaust pipe.

While most vehicles have a single exhaust pipe, though, some of them have two exhaust pipes. Known as a dual-exhaust system, it offers performance benefits. Both of the exhaust pipes perform the same task of flushing out exhaust gases, but dual-exhaust systems can improve the performance of the engines with which they are used.

The Science Behind Dual-Exhaust Systems

Some drivers assume that dual-exhaust systems are used strictly for aesthetics, but this isn't the case. Vehicles with two exhaust pipes may generate more horsepower than those with a single exhaust pipe.

The horsepower of an engine is influenced by the speed at which it can remove exhaust gases. An engine may have six or more cylinders, but unless it's able to quickly remove the exhaust gases from its combustion chamber, its horsepower will be limited. 

Dual-exhaust systems encourage faster removal of exhaust gases by providing two exit points. Exhaust gases can exit the exhaust system through two pipes rather than one. The engine can then suck in fresh air more quickly, resulting in faster combustion and more horsepower.

Protection From Back Pressure

Dual-exhaust systems help to protect against back pressure. Back pressure involves the buildup of exhaust gases in the exhaust system. Some of the exhaust gases may remain stuck inside the exhaust system for a short period, thus creating back pressure.

To protect against back pressure, some vehicles feature a dual-exhaust system. Back pressure is likely to occur when there are two exhaust pipes as opposed to one exhaust pipe. The exhaust gases will have more pipes through which they can exit. While back pressure is common with single-exhaust systems, it's typically rare with dual-exhaust systems.

Mufflers and Catalytic Converters

It's important to note that most dual-exhaust systems have two mufflers and catalytic converters as well. Mufflers are sound-dampening devices. Catalytic converters are air-filtration devices that remove harmful gases from exhaust gases.

If a vehicle has two exhaust pipes, it will typically feature two mufflers and catalytic converters. Each exhaust pipe will have its own muffler and catalytic converter.