Tasked with expelling the byproducts of combustion, exhaust systems are a key player in the areas of engine performance and fuel efficiency. In this guide, we will examine the various components that make up an exhaust, identifying the responsibilities of each piece, and noting the benefits of replacing your stock exhaust with an aftermarket upgrade.
Exhaust Systems Components
Exhaust manifolds, also called headers
: Connected to the side or sides of your engine, the exhaust manifold (or “header) is the first piece in your vehicle’s exhaust system. Gasses produced during combustion are channeled out of your engine’s exhaust valves and into the manifold, which moves the gasses into the rest of the exhaust system.
A catalytic converter. Notice the O2 sensor hole.
: The toxicity of exhaust fumes is mitigated by the catalytic converter. This device catalyzes a redox (oxidation and reduction) reaction in its chamber by exposing the exhaust fumes to precious metals. This is a mandatory piece of equipment on U.S. vehicles since 1975.
A Magnaflow aftermarket muffler
: Tasked with dampening the noise produced by your engine, mufflers are usually found towards the rear of an exhaust system. A muffler consists of an enclosed series of baffles and insulation which work together to reduce the harsh noise produced by a working engine.
: While a muffler dampens engine noise across the entire sound spectrum, a resonator is designed to cancel out specific sound frequencies. Resonators are often employed to cut unpleasant droning noises, making this part a key player in determining what your exhaust sounds like.
Segments of an exhaust pipe
: Connecting all of these items together is a series of pipes, usually made of steel. These pipes are designed to conform to the contours of your vehicle’s underbody and conduct exhaust gasses to the outlet (usually located at the rear of the vehicle). Common pipe configurations include down-pipes, X-pipes, Y-pipes, and mid pipes. The shape and purpose of these pipes are determined by your vehicle’s underbody contours.
Benefits of Aftermarket Exhaust
A side exit dual exhaust system
The factory installed exhaust system on your vehicle was designed with one major factor in mind: affordability. While functional, stock exhaust systems often sacrifice power and fuel efficiency to be inexpensive and easily mass produced. An aftermarket exhaust such as those made by Magnaflow
will improve your vehicle’s horsepower, increase your fuel mileage, and produce a more aggressive engine note. In addition to these benefits, many aftermarket exhausts are made with stainless steel which can withstand road salt and other corrosive factors that take a toll on materials of lesser quality . If you’re not prepared to invest in a complete aftermarket exhaust system, you can still customize your exhaust tone with a performance muffler
Types of Exhaust Systems
An exhaust system on an F-150.
Aftermarket exhaust systems are usually categorized by the parts of your vehicle’s exhaust they attach to or their position on the vehicle. Below are some of the more common types of exhaust systems.
Cat Back Exhaust
- Replaces your exhaust from the catalytic converter back. On modern vehicles equipped with catalytic converters, this is usually the most extensive system replacement available.
Axle Back Exhaust
- Replaces the system from the rear axle to the rear bumper. Depending on your vehicle this could be anything from a large dual-exit muffler to a simple set of pipes. Usually more affordable than other exhaust system types due to fewer parts being replaced.
Header Back Exhaust
- Replaces the exhaust system from the exhaust manifold to the rear bumper. Not as common as the cat back system, header back systems are most frequently found on track vehicles or vehicles old enough to pre-date modern emissions-control laws.
Turbo Back Exhaust
- Almost exclusively available on diesel applications, this replaces the exhaust from
the turbocharger to the back of the vehicle. Since forced induction (turbochargers or superchargers) is relatively uncommon on OEM gasoline engines, gas systems are usually limited to cat, axle, and header back configurations.
Downpipe Back Exhaust
- A variant of the turbo back exhaust, downpipe back exhausts use the vehicle’s existing downpipe, making them more affordable and easier to install at the expense of less than optimal power gains. As with turbo back exhausts, these are rarely seen on gas engines.
DPF Back Exhaust
- Replaces the exhaust from the DPF (diesel particulate filter) to the rear of the system. The simplest exhaust available for a diesel engine, DPF back usually entails a new tailpipe and muffler.
Whether you replace it in parts or in whole, changing up your exhaust can produce a wide array of improvements from sound to power and efficiency. If you have more questions about exhaust systems, contact us today and speak with one of our product experts. They’re standing by to help you choose the best exhaust for your ride.