To describe the MK3 Ford Focus as a hot-hatch would be a dramatic understatement. Third-degree hatch or napalm hatch might be better fitting descriptors. In 2015, the third generation Focus RS reached the US to massive acclaim from enthusiasts and reviewers alike. It was a first for the US market, as the RS nameplate hadn’t made it over the pond until the MK3. The MK3 Focus RS features the somewhat infamous 2.3L Ecoboost four-cylinder that also powered the 2014 Ecoboost Mustang. Despite the meager 2.3L displacement, the Focus RS produces 350 horsepower and will get to 60 from a dead stop in 4.7 seconds. Those figures are what make the RS a unique beast in the Ford lineup.

While the RS might not be wielding a high-displacement V8 behemoth under the hood, the 2.3L Ecoboost is very responsive to aftermarket additions. The MK3 Focus RS is unquestionably an exciting car from the factory. But, as with most things, it can be more exciting. One of the standout modifications that can introduce a little more verve to your RS driving experience is an upgraded exhaust system. Since the 2.3L Ecoboost is a turbocharged engine, there is quite a bit to be gained from fitting a less restrictive exhaust. In addition to performance gains, an upgraded Focus RS exhaust can introduce some additional sound into the equation for those that want to make a grand entrance.

Types of Ford Focus RS Exhausts

You’ll also need to think about what kind of aftermarket Focus RS exhaust you want to go with your car, in addition to the things mentioned above. 2016-2018 Focus RS models typically come with one of two styles of exhaust systems. Turbo-back and cat-back exhaust systems are two examples of this.

Turbo-Back Exhaust

Installing a Ford Focus RS Turbo-back exhaust system is the most demanding task. When it comes to a turbo back exhaust, practically every part of your stock exhaust is replaced. Your Focus RS’s downpipe and catalytic converter are part of this package. This enables you to increase the system’s overall diameter and, thus, the amount of exhaust gas that may escape. Because of this, turbo-back exhausts offer the most significant gains in performance. The most costly exhaust system you can buy is a Focus RS header-back, because it replaces everything. They are also the most complex to install of the two types of exhaust.

Cat-Back Exhaust

A cat-back exhaust is a frequent addition to mildly modified Focus RSs. Exhaust systems with catalytic converters sound just like that. From the catalytic converter to the exhaust tip, they replace everything in the stock exhaust system. These exhausts, which are often constructed of stainless steel, are designed to increase engine exhaust gas flow, resulting in more power and, of course, increased noise. Exhaust systems for the Focus RS may differ greatly in terms of pipe diameter, tip diameter, and exit location.

Factory Focus RS Exhaust System

The MK3 Focus RS’s original exhaust system is actually rather good, especially considering the price point of the car. For the most part, all turbocharged sports cars’ exhaust systems look a lot like the one on the RS. In the downpipe, a catalytic converter is located very close to the turbocharger. Once the 2.75″ cat-back system takes over, there aren’t too many notable or important limits. There is a second catalytic converter in several cars that are identical to the RS. According to reports, the RS does not require any additional exhaust cleaning in terms of pollutants. That should testify to the effectiveness of the 2.3-liter Ecoboost.

The factory exhaust system for the Focus RS is well-optimized. It boasts good factory flow numbers from the catalytic converter to the exhaust tips in terms of its real design. Because of this, an aftermarket Focus RS cat-back exhaust won’t have much of an impact on performance. You’ll see a substantial increase in performance with a turbo-back system Since turbo-back exhausts replace the factory cat with a higher-flowing one that removes the major source of restriction, they are more efficient. Cat-back exhaust improvements of between 5 and 10 horsepower can be expected, while turbo-back gains of around 20 horsepower should be expected.

How Does the Ford Focus RS Exhaust Valve Work?

Incorporating valves into the exhaust system is a unique feature found on the Ford Focus RS. Although valved exhausts are nothing new, there is a general lack of understanding regarding how the RS valved exhaust works in the Ford Focus community. Exhaust valves are incorporated into the RS exhaust’s left-hand muffler outlet pipe in simple words. It is controlled electronically by the PCM, which can open or close the valve.

The PCM is preprogrammed to open the valve upon a cold start in order to either annoy your neighbors or impress your friends. The valve will close once the cold start procedure is complete. As a result, it will open and close in response to the engine’s load, revolutions per minute, and speed. The PCM of the Focus RS constantly monitors and adjusts for all of these aspects. There is a noticeable variation in sound between the two valve settings, despite the fact that performance is not significantly different. According to the RS owner’s manual, exhaust limits are minimal when the valve is open. With the valve open, the RS is said to provide a more “sporty” sound. They could have been a little more descriptive, but hey, that’s the best they could do given the circumstances. Exhaust flow is reduced marginally and noise levels are greatly reduced when the valve is closed on the factory Focus R exhaust system.

The lack of a manual valve control on the stock Focus RS valved exhaust system is a major disappointment. There are a lot of aftermarket valved exhausts available for the Focus RS because of that terrible restriction.

Ford Focus RS AWE Switchpath Exhaust 

Look no farther than the AWE Switchpath if you’re searching for a high-performance Focus RS Catback system that keeps the factory exhaust’s valved functionality but gives you more control. AWE has made a name for itself in a variety of aftermarket circles. Everything from McLarens to Volkswagens may get their high-quality exhaust systems from these guys. Particularly well-known and well-reviewed are their Ford exhausts. The AWE Switchpath is a popular choice in the Focus RS community because it provides a solid balance of aftermarket performance and factory functionality.

It has a valved configuration, similar to that of the OEM Focus RS exhaust. The AWE exhaust, in contrast to the factory RS exhaust, has a switchable valve mode. The Switchpath comes with a wireless remote control that overrides the RS PCM valve control mechanism, allowing you to have complete control over your music.

In terms of performance, the AWE Switchpath Focus RS exhaust goes far beyond the novelty of the valve party trick. The piping is larger in diameter than the factory exhaust and is made completely of T304L stainless steel. The 2.3L Ecoboost engine’s gas flow is improved because to the Switchpath’s 3.0″ diameter, which results in higher power. Both resonators and no resonators are options for the AWE exhaust. If you want the least amount of exhaust drone, they suggest purchasing it with resonators. The non-resonated variant, on the other hand, is the best option if you’re searching for more power and volume.

Even though the AWE Switchpath exhaust system is the most expensive, it offers the most in terms of performance and versatility for the Focus RS.

Mountune V2X 2.3L Ecoboost RS Exhaust

Aftermarket manufacturers tend to specialize in specific brands or models, and there’s almost always one that sticks out from the rest. Mountune is the manufacturer for the MK3 Focus RS. It is safe to say that they have the most RS tuning experience and the most Focus RS performance parts available of everyone. In the RS community, the Mountune V2X is almost universally adored, and for good reason.

The Montune V2X doesn’t tamper with the original formula too much in terms of its actual construction. An increase in exhaust pipping to 3.0″ enables a little more exhaust gas to be expelled, which is the most important alteration. The exhaust drone is completely eliminated thanks to the high-flow silencer. Custom double-slip joints or V-bands connect all of the joints, ensuring the finest possible seals at all times. There are two versions of the V2X: one has a valve, the other does not. Unquestionably louder is the V2X non-valved model.

The sound that the Montune Focus RS exhaust generates is one of the key reasons for its popularity. The stock exhaust noise, according to most 2.3L Ecoboost Ford RS owners, is, to put it mildly, unimpressive. By enhancing the nature of the 2.3L Ecoboost engine under hard acceleration, the Mountune V2X corrects this problem. Many RS enthusiasts swear by the crackles and pops that come from their V2X exhaust.

COBB Tuning Turboback MK3 RS Exhuast System

Full turbo-back exhaust systems are required for optimal power and performance from your MK3 Focus RS exhaust system. Despite the fact that cat-back systems can certainly improve exhaust flow, the downpipe’s stock catalytic converter in your Focus RS is the main bottleneck here. Replaces the standard catalytic converter in the MK3 Focus RS turbo-back system with a 4.5″ high flow Gsi cat to considerably minimize backpressure.

The COBB exhaust is a 3.0″ system with a bespoke straight-through muffler and resonator that provides the right mix between sound and flow, like many of the other alternatives on this list. The COBB Focus RS Turboback uses an OEM valve that is included in the kit itself. The COBB Turboback, according to its owners, has just the right amount of rasp when pushed hard, and softens out significantly on the interstate.

The COBB Focus RS Turboback is the best of the best in terms of performance, especially when paired with a tune. Cobb is a tuning company at heart; hence, all of its performance parts are designed to be tuned. The Turboback can increase horsepower and torque by double digits when combined with a tune. According to COBB, their Ford Focus RS exhaust is so free-flowing that it outperforms the stock turbocharger. If you’re looking to make a lot of power, the COBB Turboback is the way to go.

Focus RS Milltek Exhaust Sport Cat-Back