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How Does an Armytrix Exhaust System Increase Horsepower?

As an enthusiast, you probably know that an aftermarket exhaust will add power to your car, or at least that’s what the internet says. The idea is that with a less restrictive exhaust your car gains power. What confuses many people is why a less restrictive exhaust gains power. Things like thermal efficiency, scavenging, velocity, and total flow all matter and can separate a great exhaust from a bad one. In this short article, we’re going to dive in-depth on everything you need to know about Armytrix exhaust systems and how they increase power.

As you probably know, exhaust gases are a byproduct of combustion. After the engine goes through the intake, compression, and ignition cycles, it now has hot gases it needs to expel to continue the cycle. The exhaust valve opens, and the piston comes up, forcing the air out of the engine and into the exhaust system. The purpose of the exhaust system is to route these potentially harmful gasses away from the cab of the vehicle and to the rear or sides.

Bigger is Always Better, Right?

Once the exhaust gases are forced out of the cylinder, they flow through the exhaust ports of the cylinder head(s) to the exhaust header(s). The gases come out in pulses, and if the headers are correctly designed, the low-pressure zone behind the pulse can help pull the next pulse along at a faster rate. This is known as scavenging and is one of the critical components to an aftermarket exhaust making more power compared to the stock exhaust.

After the header(s) is the rest of the exhaust system, which is typically comprised of a catalytic converter, mufflers, and resonators. In turbocharged cars, the exhaust gases flow through the exhaust housing of the turbocharger, then exit through a downpipe which mates up to the rest of the system. Depending on the size of your engine, how much power you’re trying to make, and a variety of other factors, the size of the piping will effect exhaust flow. The general idea is that a larger diameter is always better, but the law of diminishing returns applies; for example, a 5” exhaust on a four-cylinder engine is unlikely to make a difference in power compared to a 3” exhaust.

Heat is Energy

In case you didn’t know, heat is energy. As exhaust gas cools, its velocity decreases. Harnessing this energy isn’t extremely important for a naturally aspirated vehicle, but it’s important for turbocharged vehicles. With hot, high-velocity exhaust gases entering the turbocharger, the turbine can be spun faster resulting in better spool times, more power, and ultimately much better thermal efficiency. You can harness even more of the energy by using an exhaust wrap which is designed to keep the heat inside the header instead of it dissipating to the air under your hood.

Back Pressure Myth

All over the internet are “experts” claiming that four-stroke engines need ‘x’ amount of back pressure to run properly. This is entirely false. You see, with less back pressure the gases can exit the cylinder faster, resisting the upwards force of the piston less, and allowing the engine to rotate easier and ultimately make more power. The reason so many internet “experts” claim that you need back pressure is that unless a huge amount of time is spent on research and development, creating an exhaust system with no back pressure, great scavenging, and a great sound is basically impossible.

In general, a well-designed exhaust system is designed with a focus on improving scavenging and back pressure is not as large of a concern. To put it simply, most performance exhaust systems have a small amount of back pressure, as tuning that absolutely nothing is borderline impossible unless you are just running some sort of open header system which will be incredibly loud and is not something you want for the street. The real gains are in improving scavenging as much as possible, with decreasing back pressure also being a factor to power improvement.

How we do it

In general, larger piping diameter means more power, but that does not mean all exhaust systems are created equal. Armytrix focuses on not only improving flow, scavenging, and decreasing back pressure, but also on fine-tuning the exhaust note and keeping the entire design lightweight. Not only will an Armytrix exhaust increase power, but it will also be lighter than the stock exhaust, and our Valvetronic system allows you to quickly and easily change the exhaust note on the fly.

Bryce Cleveland Aug 28, 2018 ARMYTRIX USA 0 Comment Read More

Video: 2018 991.2 Carrera S Spitting Flames with Armytrix Exhaust

As Porsche moves towards turbocharged engines across their lineup of vehicles, including their coveted 911, a lot of enthusiasts were worried that these new Porsches would sound terrible compared to the old naturally aspirated Porsches. Although there may be some people out there who refuse to think turbocharged engines sound good, most of us have accepted this new turbocharged sound from Porsche and have learned to love it. Straight from the factory, the Carrera sounds pretty good, but it’s on the quiet side. The problem with many aftermarket exhausts is finding a middle ground between the exhaust being too loud and too quiet. This is where the Armytrix Valvetronic exhaust comes in, which allows you to change the volume on the fly.

Our Valvetronic system works by using a valve to direct the exhaust gases through a muffler or to bypass the muffler. With the valves closed, your Carrera with still be relatively quiet, but with the valves opened it turns in an absolute monster. On top of the awesome sound under loud, while engine braking these new Carrera’s love to pop and spit flames. Check out the quick dyno run below showing off this exhaust!

Bryce Cleveland Aug 07, 2018 Porsche 0 Comment Read More

Video: Nissan R35 GTR with Armytrix Exhaust

Although the Nissan GTR is one of the best bang-for-buck high-performance cars on the market, there is always room for improvement. Straight from the factory, the GTR is relatively quiet because it needs to appeal to a wide range of potential buyers, and many people don’t like loud cars. Us enthusiasts want to hear our car when we put the pedal down, but sometimes you also want your car to be quiet, so you don’t piss off your neighbors. This is where we come in with our Valvetronic exhaust, which allows you to change the volume of your GTR on the fly.

Armytrix is a very big name in the GTR market, and as such we have the opportunity to meet a lot of cool GTR owners. @mpolito97 is one of those cool GTR owners. With an awesome set of Advan wheels, a big APR wing, and an Armytrix exhaust, his GTR is a beast. Check out the exhaust video below showing off his GTR and that awesome Armytrix sound!

Bryce Cleveland Jul 10, 2018 ARMYTRIX USA 0 Comment Read More

Video: FK8 Civic Type R Armytrix Exhaust Cold Start

A couple of weeks ago we posted a quick sneak peek video of the new Armytrix FK8 Civic Type R exhaust, and it got a lot of attention. Development has moved farther along, and we are getting pretty close to the full product launch. With that, we have more sneak peek videos to show off just how aggressive our new exhaust system sounds. Of course, it doesn’t always have to be loud thanks to our Valvetronic system which allows you to change the volume on the fly.

The particular FK8 in this exhaust clip is one of our US-based test vehicles and is currently using the burnt titanium tips, but there will also be Stainless Steel, Matte Black, and Carbon Fiber tips available for the full launch. Separate from the catback exhaust are Armytrix downpipes, which are on the Civic Type R in the video below. The downpipes will be available in ceramic and non-ceramic coated versions, both of which are catless for maximum flow and performance. Check out the sound clip below!

Bryce Cleveland Jun 12, 2018 ARMYTRIX USA 0 Comment Read More

Sneak Peek Video: Armytrix FK8 Civic Type R Exhaust

Although the FK8 Civic Type R the most powerful front-wheel-drive production car ever and has a phenomenal chassis, there is always room for improvement. Many factory components are heavy and hold the engine back. A full turbo-back exhaust is a great way to shed some weight, add some power and add some sound to your FK8 Type R, of course, it was only a matter of time until Armytrix got their hands on a Civic Type R for exhaust development. The full system isn’t available in the US just yet, but that’s just a matter of time. For now, though, we have this awesome exhaust clip to enjoy!

Of course, like every Armytrix exhaust system, this new one for the FK8 Type R will include our world famous Valvetronic system. The Valvetronic system allows you to change the tone of your exhaust on the fly quickly. In the case of the Civic Type R, with the valves closed it has a quiet but sporty sound and with the valves open it sounds incredible. Be sure to check out the full sound clips below and keep your eyes peeled for this exhaust to be available in the US!

Bryce Cleveland May 22, 2018 New Products 0 Comment Read More