Single vs Dual Exhaust Systems

Dual exhaust systems, as the name implies, use two exhaust pipes. The question is, are they actually any better than the single exhaust you find on most cars? If there is a difference, what exactly is it? It’s worth knowing that two pipes aren't always a sign of a dual exhaust system. There are single exhaust systems that feed to dual pipes.

Single Exhaust System

Most cars or vehicles you buy will only come equipped with a single exhaust system. They’re used because they’re perfectly efficient for most vehicles. Single exhaust systems are compact and lightweight, and simple.

The exhaust tubes all go into one collector that’s very close to the engine, then routes out along a single pipe from the muffler for the exhaust gases. They cost less to produce and install because there are fewer parts. There’s one great failing about single exhaust systems, and that’s what’s called absolute flow. The problem is that the diameter of the tubing isn’t large enough for the system, but there’s little that can be done about it because of the ground clearance needed for the vehicle.

Dual Exhaust Systems

Real dual exhaust systems, found on muscle cars and hot rods, consist of two mufflers, two catalytic converters, and a pair of tail pipes. The twin pipes aren’t just for show. Dual exhaust systems can increase the efficiency and horsepower of an engine. As a general rule, you’ll only find dual exhaust systems on V6 or V8 engines, since they have twin manifolds, which are necessary for dual exhaust systems.

Where dual exhausts occur on smaller vehicles, they’ll be what’s known as an exiting dual system. What this means is that the muffler has been modified so it has two exhaust pipes, nothing more than that. With a dual exhaust, more of the exhaust actually exits through the system and in turn increases the horsepower. This is an improvement in the performance of the engine. On the downside, the result is greater emissions.

Dual exhaust system with narrow tail pipes will produce a lot of torque because the exhaust gases are forced through the pipes more quickly. The larger the pipes, the lower the torque. Dual exhaust systems tend to be noisier, although that’s not always the case. With proper mufflers they shouldn’t be especially noisy, although the pitch of the exhausts might be different, and dual exhaust systems often naturally produce more noise.

Crossover Dual Exhaust

The crossover dual exhausts are slightly different systems and some believe they’re the ideal system. It doesn’t have the pressure imbalance often found in dual exhaust systems, due to the X-pipe crossover, which makes it easier for the gases to exhaust. The only downside is the size, which makes the system’s clearance too low for most cars, and therefore generally not viable.

Single To Dual Systems

The single to dual exhaust systems are really modified single exhaust systems. However, that modification makes is almost as effective as dual exhaust systems, especially when fitted with oval pipes.