Catalyst vs. Flame arrester

The struggle of automotive engineers for environment has led to appearance of units that are not used for movement, but reduction of air pollution. Catalyst is one of them. A metal can with a ceramic honeycomb system "burns" exhaust gases inside and reduces the harmfulness of car exhaust. According to experts, you need to get rid of a catalyst after 150-200 thousand kilometers. It is for such a run that this node is designed. It’s better to do it as soon as fuel consumption starts to increase and the car starts to accelerate worse.


Removing catalyst and installing a flame arrester will cost much less than replacing catalyst itself. But removing of catalyst will increase toxicity of emissions, so this option is not suitable for people concerned about environmental safety of our planet.


But catalytic converter is not eternal, sooner or later the catalyst is clogged, its cells are destroyed, and it not only ceases to fulfill its functions, but also prevents the engine from working. So which are the options for a car owner regarding replacement?

Catalyst vs. Flame arrester β€” Photo β„– 1 | AutoCatalyst Market


It is possible to replace a faulty catalyst with a new one, however such a replacement will cost a good sum of money. Such catalysts are very expensive. The cost goes up to a quarter of market value of a used car. But there are models where several catalysts are installed, and each should be changed in case of breakdown. Naturally, the majority of car owners prefer a more economic resolution, like installation of a flame arrester instead of a catalyst.

The advantages of this approach are the following: 

  1. Lower price. Replacing the catalyst with a flame arrester can cost 5-10 times cheaper than buying a new cat. There are no comments here.

  2. A slight increase in engine power and lower fuel consumption. The flame arrester creates less resistance to exhaust gases than the catalyst, engine "breathes” better, which means it adds to the power. The increase, as well as fuel economy, is not very large, about 5-10%. Most drivers will not feel it. It is not worth it to specially remove the catalyst for the sake of increasing power, but for those who still decide on this procedure, improving engine performance is a small bonus.

  3. Reduced fuel quality requirements. Catalysts react most sharply to bad quality gasoline and often it is because of that quality, catalyst fails. The flame arrester does not cope with such work. This does not mean that after replacing a catalyst, refueling at cheap gas stations will be a good idea, but you don’t have to worry about an expensive and fragile part when using unfamiliar gas stations.

Catalyst vs. Flame arrester β€” Photo β„– 2 | AutoCatalyst Market

Catalyst Cons are the following: 

  1. First of all, ecology. If you are proud that your car doesn’t pollute environment, then after replacing the catalyst with a substitute, you need to stop doing this, because your car will no longer have Euro-4 or Euro-5 standard.

  2. No need to program car computer. Vehicle electronic control system is designed to use a catalyst and without it will start to go crazy. Using a substitute, you need to invent tricks on oxygen sensors, and in the best case, reprogram the engine.

  3. Reducing the resource of exhaust system. Even a good catalyst substitute with the task of lowering the temperature of exhaust copes worse than the catalytic converter, so the risk that the muffler burns out increases. On the other hand, you can change more than one silencer for money that will save a flash suppressor.


If benefits of replacing catalyst with a flame arrester are obvious for you, then a detailed instruction of step-by-step process will be useful. Usually car owners have to deal with universal flame arresters, which must be adjusted locally, or even make such a unit on their own. People without experience with a grinder and welding should not take up the replacement.

Step 1. Removal of the catalyst

The catalyst and collector are located directly in the exhaust manifold. Catalyst is easier to remove, especially if the design permits to use a screwdriver. If there are no such a possibility, because they are tightly attached, a grinder is used. The second one requires dismantling the exhaust manifold, which increases the complexity of process.

Step 2. Choosing a flame arrester

The supply of such car parts is sufficient, you can consider the details, cost and other elements. In general, the main thing is that it is two-layer, the brand is not so important. However, this is such a simple unit that you can do it yourself. Cut the casing from the catalyst, knock out the entire filling from it, and instead insert a piece of perforated pipe, cover the casing from the inside with heat-resistant, sound-absorbing material, brew and the arrester is ready. As for cost, such an assembly will turn out to be very cheap, but only those who know how to use a welding machine should undertake independent manufacture of a flame arrester. As practice shows, the most popular damage to flame arrester is a burst weld.


Catalyst vs. Flame arrester β€” Photo β„– 3 | AutoCatalyst Market

Step 3. Installing a flame arrester instead of a catalyst

If we are not talking about products that are precisely designed for regular places, then to install a catalyst substitute you have to use a combination of welding and ingenuity. It’s not that it’s very difficult, but you have to measure and adjust the dimensions, think over the location, especially when it comes to collector arresters. In addition, no manufacturer describes such a procedure in official reference materials, so you need to look for information in additional sources.

Step 4. Correction of electronics

For the car to work correctly without catalyst, you need to consider reprogramming for the second lambda probe, or completely reflash the motor. The deception is like a catalyst in miniature, it “filters” a piece of exhaust that enters the sensor, showing that everything is fine, the emulator simply transfers the values ​​that it expects to the engine, without real measurements. Deceptions and emulators may not work, but a good alternative firmware almost always solves problems after installing such a device.


Catalyst vs. Flame arrester β€” Photo β„– 4 | AutoCatalyst Market


What is the general cost to replace the catalyst with a flame arrester? Units themselves are relatively inexpensive from 15 to 20 USD, depending on the brand and design. Prices for catalyst replacement services depend on region and brand of car. Average price would be 75-100 USD for such a service (although the price range is very large). Separately, you will need to pay extra for installing a lambda sensor and reprogramming.


Talking about catalyst its starting cost will get even up to 1200 USD, which is not a limit, due to various car models. That is why in case of a problem with catalysts it is very reasonable to pay attention to other options (which can be 10 times cheaper!). Savings are obvious, and replacement can be done by yourself or in most car service stations, the main thing is not to forget to adjust engine and electronic system.