When it comes to exhaust, the terminology can be a little intimidating. That’s why we’ve put together this handy guide that explains what the different types of exhaust system upgrades are.


For illustration purposes, we’ve selected images of a few specific examples, but these terms will apply to nearly all make and model vehicles.

Exhaust Systems are a very subjective category, as the best exhaust for you is the one that sounds the best to -your- ears. That’s why we produce special videos that let you HEAR the SOUND of the exhausts we offer. So whether you just want 3″ Exhaust Pipe, want a set of great looking quad exhaust tips or if you are after a very specific sound – quiet or aggressive, ModBargains offers the best Performance Exhaust brands out there to ensure you’ve got options. We offer many aftermarket parts and accessories as well, since we’re not like your average exhaust and muffler shop. Choosing an exhaust for your vehicle isn’t as straightforward as it was back in the Muscle-Car days – Our Modification Experts can recommend an exhaust that suits the character you want your exhaust to exude.

Axle-Back Exhaust

This is the best option for those on a tighter budget or mainly after sound or aesthetics. This type of system usually only replaces the mufflers aft of the rear axle, hence “axle-back”. Many manufacturers offer Axle-Back options including but not limited to: Remus Exhaust, Active Autowerke, Air Flow Engineering (aFe), Berk Technology, Borla, Flowmaster, Korkar Performance Engineering (KPE), Magnaflow, Mustang RTR, SLP and Solo Performance.

Cat-Back Exhaust

This is the most common choice for upgrading your exhaust system. This type of exhaust system includes different mufflers like an Axle-Back system but also includes larger diameter exhaust tubing and spans the length of the exhaust system aft of the catalytic converters, hence the term “Cat-Back”. This type of exhaust system is more expensive, but offers tangible performance gains as well as an improvement in sound and aesthetics. An even wider variety of Cat-Back systems are available from the finest names in exhaust, including: Remus Exhaust, Active Autowerke, Air Flow Engineering (aFe), ARK Performance, AWE Tuning, Berk Technology, Billy Boat Exhaust, Borla, Cobb Tuning, Eisenmann, Flowmaster, Gibson Extreme, HKS, Injen, Invidia, Neuspeed, JBA and Milltek Sport.

Turbo-Back Exhaust

A turbo back exhaust is specific to turbocharged cars. This type of system pairs a typical “cat back” system with a High-Flow Downpipe, which effectively replaces the entire exhaust system after the turbocharger. This type of system will deliver the greatest power and torque gains as well as the improvement in looks and sound. Often, people will pair a downpipe upgrade with a cat-back exhaust system as individual items to allow them to tailor their system to their tastes rather than purchase a complete “turbo back” kit. It’s important to mention that catless downpipes aren’t legal for street use, but most catted downpipes are 49-state legal (though you should check your local laws/regulations.). Several manufacturers offer Turbo Back systems, including Kline Innovation, Remus Exhaust, and Supersprint Exhaust to name a few, and there are many more.

Headers aka Exhaust Manifolds

Headers, as they are commonly called, are the exhaust manifolds – most commonly, “headers” refers to a high performance exhaust manifold. They can be manufactured in cast iron, cast aluminum, 304 Stainless Steel or even exotic materials like Formula-One grade Inconel 625 alloy. In the case of a naturally aspirated or supercharged (non-turbo) vehicle, the exhaust manifolds are connected to the exhaust ports on the Cylinder Head of the engine and channels exhaust gases out of the engine and directs them into the exhaust pipe at the outlet of the headers. These offer performance increases by smoothing out the flow of exhaust gas out of the engine, allowing the engine to operate more efficiently and thereby make more power. the enhanced design can remove or relocate catalytic converters integrated into the OEM manifolds in some applications and some are engineered for precise equal-length manifold runners (“equal length headers”) for even greater gains and efficiency. Supercharged engines in particular, will respond more to a set of headers than a naturally aspirated car. There are two main types of “headers”.

-Shorty Headers
Shorty headers, as their name implies, are short and only span the distance between the engine cylinder head and the catalytic converter (or turbocharger, in the case of a turbo car). This is the most common style of header. For example, BBK Performance offers Shorty Headers for Ford Mustang GT as well as Long Tube headers.

-Longtube Headers
Used primarily on naturally aspirated or supercharged cars, long tube headers eschew the catalytic converters complete and use long exhaust runners to create both an incredible, unique sound as well as deliver significant power changes. These are more expensive, and also much trickier to install than shorty headers. Long Tube headers are especially popular on Domestic Muscle V8 applications, such as BBK Performance Long Tube Headers for the Ford Mustang GT or Kooks Long Tube Headers for Chevrolet Camaro SS and SLP even offers Long tubes for the Pontiac GTO and Pontiac G8.


The downpipe is a part of the exhaust system only on turbocharged vehicles. The downpipe is the part of the exhaust system that connects from the turbocharger’s outlet to the rest of the exhaust system. Many OEM downpipes feature integral catalytic converters, which are often highly restrictive. Performance downpipes streamline the flow of exhaust gases out of the turbo for better throttle response, faster spool-up and more power and often either omit the catalytic converter or replace it with a high performance unit.
 A redesigned Downpipe for B5 Audi RS4 engine from Wagner Tuning, for instance, is a re-engineered version of the OEM pipe that eliminates restrictions in the OEM system for enhanced flow. This results in much faster turbocharger spool-up times (less lag), enhanced exhaust sound and significantly improved power. Generally speaking, most downpipes will yield similar results. A downpipe is a great bang-for-the-buck modification for most turbocharged vehicles and really unlock the potential of your turbocharged motor. A multitude of manufacturers offer Catted Downpipes for a wide variety of turbocharged models, from the popular BMW N54 and N55 turbo sixes to the supercar-killing Nissan GT-R.  We offer a wide selection of performance Downpipes manufactured to the highest engineering standards, including: Remus Exhaust, AR Design, Active Autowerke, Air Flow EngineeringAWE Tuning, Cobb Tuning, Eurojet, Evolution Racewerks, Korkar Performance Engineering, Milltek Sport, Steve Petty Motorsports (SPM), Supersprint Exhaust, Tanabe and Wagner Tuning.

High-Flow Catalytic Converters

It’s common knowledge that the catalytic converters equipped on most cars are designed with cost and emissions control in mind, rather than performance. As such, they’re often restrictive and dampen the potential output of your vehicle. By removing the catalytic converter (this may not be legal in your area, consult local laws before cutting out your cat please), exhaust flow is streamlined and a huge source of restriction is removed. This, however, often leaves cars smelling of unburnt fuel from their exhausts. This is why High Flow Catalytic converters are such an attractive option. These performance catalysts still filter your exhaust but are designed with flow and performance in mind, resulting in power and torque gains and enhanced throttle response without removing the cat completely. High flow cats are popular for both forced induction and naturally aspirated applications. More and more manufacturers are offering High Flow catalyst options as emission control systems of today’s vehicles become increasingly complex. We offer Performance and Racing Cats from these fine manufacturers:
 Remus Exhaust, BBK performance, Billy Boat Exhaust, Berk Technology, Cobb Tuning, FabSpeed, Korkar Performance Engineering, Magnaflow, Milltek Sport, SLP, Steve Petty Motorsports (SPM), Solo Performance and Supersprint Exhaust.

Test Pipes

The word “Test Pipes” is a little vague, but these are straightforward. Test Pipes are literally simply sections of straight tube that are typically installed in place of a catalytic converter. They can also be called Cat Delete pipes. The name is because they are not usually legal for street use and are for off-road or “test” purposes only, rather than as a regular piece of equipment for a street car. These are a fine choice if you have a track-day-only project car or if you want to remove your cats for a track day.   Test pipes are available from Berk Technology, Evolution Racewerks and Supersprint Exhaust.
The main thing most people are after when upgrading their exhaust is how it sounds, with how it looks coming in 2nd and how well it performs in 3rd. ModBargains cutting edge video team is constantly producing new videos showcasing just what your future exhaust upgrade will look and sound when it’s installed. Check out our Exhaust Systems playlist from our YouTube Channel below.

ModBargains knows that when it comes to  exhaust, personal preference for the sound is one of the most important things to our customers. That’ why we offer a comprehensive selection of exhaust options so that with our Experience, Expertise and Enthusiasm, we can pair you up with the sound and performance that suits your tastes.

We offer exhausts from AWE TuningRemus ExhaustAir Flow Engineering (aFe)AR DesignBilly Boat PerformanceMilltek SportNeuspeed, STaSIS Engineering, Eisenmann Exhaust SystemsBorla, Magnaflow, Evolution RacewerksWagner TuningRogue Engineering and more. Give one of our enthusiastic Modification Experts a call today at
714-582-3330 or chat online now to get started.

Story by Nicholas Gregson