The replacement costs on catalytic converters are quite pricey and most people would question whether or not it’s worth having them replaced. Although the prices can be high the catalytic converter is essential to your car and to the earth’s atmosphere.
By law, all cars, trucks, buses and motorcycles should have an integrated catalytic converter. If your car doesn’t have a catalytic converter you could face fines of up to $10 000 in some states. To avoid legalities you should always get your catalytic converter checked and replaced when you need to.
For a full guide on catalytic converters continue reading. Perhaps the top 10 product reviews on the list will aid you in selecting a catalytic converter best suited for your budget without compromising on quality.
- Features to Consider in Good Catalytic Converters
- Top 10 Best Best Catalytic Converters 2024
- 1. Nissan Altima 2.5L Direct-Fit
- 2. MagnaFlow 51356 Universal Catalytic Converter
- 3. EvanFischer REPG960301 Silver Powder-Coated Catalytic Converter
- 4. Flowmaster 2230130 223 Series
- 5. Walker 15634 Catalytic Converter
- 6. AutoSaver Universal Catalytic Converter
- 7. MagnaFlow 27402 Direct Fit Catalytic Converter
- 8. FlowMaster 2230125 Catalytic Converter
- 9. MagnaFlow 447206 Universal Catalytic Converter
- 10. Pontiac G6 Catalytic Converter
- Guide to Buying the Best Catalytic Converters
- Final Thoughts
Features to Consider in Good Catalytic Converters
What is a Catalytic Converter?
A catalytic converter eliminates any unburned fuel and toxic gasses produced by a vehicle’s exhaust before the toxicity is released into the atmosphere. It reduces vehicle emissions and greenhouse gasses.
What Does a Catalytic Converter Do?
It’s essentially an exhaust emissions control. It converts carbon monoxide, nitrogen oxides and hydrocarbons into less harmful emissions:
- Carbon monoxide is rendered into carbon dioxide
- Nitrogen oxide is converted into nitrogen and oxygen
- Hydrocarbon is turned into carbon dioxide and water
How it’s Made
A catalytic converter is simply a stainless steel box that’s attached to the muffler. The box contains beads and it’s coated with catalysts on the inside usually with compounds such as alumina & ceria. The compounds can be combined with the following materials:
- Palladium
- Rhodium
- Platinum
- Gold
Catalytic converters also have sensors which regulate fuel and air passing through your vehicle’s engine.
Where is it Located?
The catalytic converter is located between the muffler and the engine. A catalytic converter is not to be confused with an engine component as its part of the exhaust system.
You’ll notice that most modern vehicles such as SUVs come with more than one catalytic converter. Trucks also have two catalytic converters as they’re big and tend to emit the most CO2 into the environment. Bigger vehicles need more powerful emissions control systems.
Smaller vehicles will only have one catalytic converter and motorcycles too. Catalytic converters aren’t only used for cars. Mobile machinery such as tractors and excavators can also have integrated catalytic converters as well as trains.
Types of Catalytic Converters
Two-Way Converter
The two-way catalytic converter is usually used in diesel engines. It performs two tasks at the same time:
- Converts carbon monoxide into carbon dioxide.
- Changes hydrocarbon into carbon dioxide and water.
Two-way catalytic components convert two toxic gasses into less harmful pollutants.
Three-Way Converter
The three-way catalytic converter is essentially used in all petrol based vehicles. Three-way converters perform the same task as two-way converters but they convert an additional toxic gas. This converter changes nitrogen oxide into nitrogen and oxygen.
Catalytic Converter Fittings
To modify or upgrade your vehicle with a catalytic converter you’ll need to purchase a component that fits your car. There are two types of catalytic converters you can opt for; the direct fit or the universal fit.
Direct Fit Catalytic Converter
A direct fit catalytic converter is bolted directly into your vehicle. These converters are best suited for OEM (Original Equipment Manufacturing) styled exhaust systems or one that’s factory fitted. The direct fit is to reduce additional modifications on a vehicle.
With a direct fit catalytic converter, you won’t have to spend additional cash to modify your vehicle so the component can fit into your car. Installation is easy, they’re more reliable and they’re endorsed by manufacturers.
Universal Fittings
A universal fit is not an OEM component. You’ll need additional modifications and alterations done on your vehicle in order to fit a universal catalytic converter. Although universal fits are generally cheaper the installation is more labor intensive.
You’ll need various tools to install a universal catalytic converter. Components and vehicle specific parts will need to be purchased separately. Installation is not easy and it will take a lot of time & the additional components and modification needed for a universal fit may cost you more.
Now which one should you use?
Top 10 Best Best Catalytic Converters 2024
1. Nissan Altima 2.5L Direct-Fit
Editor’s Rating:
It’s one of the best catalytic converter brands on the market as it provides optimal performance for your vehicle.
Key Features
The Nissan Altima catalytic converter’s outer shell is made with durable stainless steel. Internally the converter has a honeycomb structure to provide maximum flow.
To avoid MIL (malfunction indicator lamp) the Nissan Altima’s internal layers have been engineered with precious metals for optimal performance. The catalytic converter has direct bolts that allow the component to be installed into your vehicle without additional modifications.
The Nissan Altima catalytic converter is stamped with a genuine Federal EPA certification and it’s OBDII compliant. It’s also important to note that it’s not CARB (California Air Resources Board) compliant and will be illegal to use in the state of California.
Why Use the Nissan Altima Converter?
The internal honeycomb structure allows catalysis to fully react with exhaust gasses without compromising on the flow rate, therefore, reducing back pressure. The increased exhaust flow improves the performance of your vehicle.
You’ll experience increased horsepower and it will reduce your gas mileage. The Nissan Altima catalytic converter will reduce the effects of your engine overheating. It’s also a direct fit which means it’s user-friendly as the Nissan Altima is of OEM standards.
The Nissan Altima catalytic converter also eliminates the check engine light and removes restrictions that hinder your vehicle’s overall performance. It’s a high quality component made from premium materials for durability. It’s also extremely economical making it better value for money.
Pros
- Provides maximum efficiency
- Easy installation
- Premium materials
Cons
- Some bolt holes don’t match
2. MagnaFlow 51356 Universal Catalytic Converter
Editor’s Rating:
The MagnaFlow 51356 catalytic converter has been carefully engineered to work well with both petrol and diesel applications.
Key Features
MagnaFlow’s universal catalytic converter is constructed from stainless steel for durability and strength. The body type is a clamshell with a 2,5″ outlet and a 2,5″ inlet. The oxygen sensor location is midbed. The substrate material is made from ceramic for an even flow.
It’s a universal converter so you may need additional modifications to install it. The MagnaFlow converter is Federal EPA compliant but it’s not CARB approved.
Why Use the MagnaFlow Converter?
The MagnaFlow universal catalytic converter is designed to keep your engine check light off. CNC robotic manufacturing was used for precision and durability of the unit. The catalytic converter exceeds EPA requirements and it’s made according to OEM standards.
MagnaFlow’s universal converter is designed to improve your vehicle’s overall performance by increasing horsepower and it decreases fuel consumption. There’s an even flow of oxygen so there won’t be any back pressure.
If your car is showing emissions codes it’s best to check your spark plugs, engine and all the components in your vehicle before changing the converter. It’s known to be easy to install however you may need additional assistance as it does require cutting and welding.
The MagnaFlow converter is made with premium materials and it’s an inexpensive component. It has a 50 000 mile construction warranty as well as a 25 000 emissions warranty.
Pros
- Robust
- Works well with diesel engines
- Economical
Cons
- Doesn’t fit some vehicles
3. EvanFischer REPG960301 Silver Powder-Coated Catalytic Converter
Editor’s Rating:
The direct feature means that the EvanFischer catalytic converter is easy to install. Your car won’t need any additional modifications in order for you to install the converter.
Key Features
EvanFischer’s catalytic converter is manufactured using aluminized steel for durability. It has a dual outlet and a single inlet for maximum flow. The oxygen sensor port’s location is upstream & downstream.
The EvanFischer has four oxygen sensor ports. The Y-shaped pipe design allows for a direct fit which makes it OEM standard. There is also hardware included such as gaskets, bolts and nuts. Assembly for the converter is on the driver and passenger side.
EvanFischer’s catalytic converter is federal EPA certified but is not of CARB standards. It has a 50 000 mile warranty.
Why Use The EvanFischer Converter?
The direct fit component is made for long lasting durability and protection. It’s easy to install with no modifications needed such as cutting or welding. The EvanFischer catalytic converter is manufactured according to industry standards for reliability.
EveanFischer’s direct fit converter improves the performance of your vehicle and eliminates the emissions code. The converter increases horsepower and minimizes engine heat. The four oxygen sensor ports increase a maximum flow which minimizes back pressure and adds protection for your engine.
The catalytic converter fits well into most vehicles as it is an OEM component.
Pros
- Easy installation
- Robust
- Economical
Cons
- May start to rattle
4. Flowmaster 2230130 223 Series
Editor’s Rating:
The Flowmaster converter has excellent flow characteristics. It’s a versatile component that’s a direct fit which is of OEM standards.
Key Features
Flowmaster’s catalytic converter is made with premium stainless steel on the outer shell for durability and strength & the substrate is made with ceramic. The body length is 10,50″ and the width is 4″ & the body shape is round. It has flip-fit inlet and outlet connections.
The Flowmaster converter is a 3-way converter style for vehicles that are 5500lb in weight and engine size of 5,9L. It’s not of CARB standards but it is Federal EPA approved in 49 states.
Why Use the Flowmaster Converter?
Flowmaster’s catalytic converter meets the requirements for a wide range of applications. It’s made with premium materials to ensure durability and strength. It’s a universal component which means you may need to use additional modifications such as cutting and welding before installation.
The precious metals and internal substrates have been carefully engineered for maximum efficiency. It decreases MIL codes and improves your vehicle’s acceleration as well as fuel consumption. The Flowmaster catalytic converter takes care of foul exhaust smells and it’s easy to install.
It’s a tight and compact component that is suited for hobbyists as it doesn’t require much work to fit into your vehicle. It provides maximum flow which protects all the other important components in your car.
Pros
- Reduces exhaust smells
- Made from premium materials
- Has a ceramic core
Cons
- May start to rattle over time
5. Walker 15634 Catalytic Converter
Editor’s Rating:
It’s an easy to install converter that doesn’t require professional work as it’s an OEM standard design. The Walker catalytic converter is also available for pre-OBDII vehicles which means it can be used for car models from 1995 and older.
Key Features
The Walker 15634 catalytic converter is manufactured using stainless steel on the outer shell for durability. The catalytic converter’s internal substrate is made with ceramic for maximum flow. The body shape of the converter is a standard oval shape with a height of 4,25″ and a width of 6,125″.
It has a four bolt welded flange inlet connection type and a pipe for the outlet connection. It has no O2 sensor ports and no air tubes but it is Federal EPA certified.
Walker’s catalytic converter is made with aluminized piping and it comes with heat shields for maximum longevity. The thick OE flanges, brackets and hangers ensure the converters overall strength.
Why Use the Walker Converter?
The Walker converter is manufactured to meet your vehicle’s standard emissions requirements. The body and heat shields are made with premium quality materials that ensure durability & stability. It also includes a gasket and a pipe assembly for easy installation.
It’s both universal and a direct fit which means it will fit older & newer applications easily without any hassles with the installation. The OE style routing and hanger position make it easy to install.
The Walker catalytic converter provides optimal performance for your vehicle and protects the other components in your car from contaminants and fouling. It also eliminates foul exhaust smells and has a maximum oxygen flow.
Pros
- Made with premium materials
- Increases horsepower
- Robust design
Cons
- Not a CARB component
6. AutoSaver Universal Catalytic Converter
Editor’s Rating:
This catalytic converter exceeds OE standards without sacrificing the flow rate of the component.
Key Features
The outer shell of the AutoSaver converter is made with durable stainless steel material and the internal substrate is made from ceramic. The body is a round shape with an inlet diameter of 2,5″ and an outlet diameter of 2,5″.
The length of the body is 13″ and is suited for vehicles with a 2,25″ OD exhaust pipe. It can fit applications with an engine of 5,9L. The AutoSaver universal catalytic converter is stamped with a certified Federal EPA stamp which makes it OBDII compliant.
Why Use the AutoSaver Converter?
AutoSaver manufactures durable catalytic converters that have long service lives. The universal converter has high emissions control with stable performance and reliable quality.
AutoSaver’s catalytic converter avoids MIL (malfunction indicator lamp) issues that are common with lower grade components. The honeycomb design reduces the effects of harmful emissions without minimizing the flow rate.
The increased flow rate improves your vehicle’s performance by increasing the horsepower and decreases fuel consumption. It protects your engine from overheating and it eliminates foul exhaust smells. It’s not of CARB standards but it is an OEM component which means it will fit most applications.
Pros
- High performance component
- Durable
- Ceramic core
Cons
- Tends to clog up
7. MagnaFlow 27402 Direct Fit Catalytic Converter
Editor’s Rating:
The MagnaFlow 27402 catalytic converter is a versatile component that fits myriads of applications as it’s an OBDII compliant unit that can be used for newer vehicles.
Key Features
MagnaFlow’s catalytic converter is made with robust stainless steel on the outer shell with a metallic finish. The internal substrates are made from ceramic. It’s a direct fit component with a 2″ diameter on the main pipe. The overall length of the converter is 16″.
The seam is welded close to the converter body for a robust and tighter bond. This product also includes a gasket.
Why Use the MagnaFlow Converter?
Although the MagnaFlow catalytic converter is not of CARB standards it is a Federal EPA certified component. It’s known to exceed EPA requirements to stabilize the emissions of your vehicle. This means this component will minimize fouling in all parts of your vehicle.
The MagnaFlow is manufactured with CNC robotics for precision which also contributes to the OEM standards of the converter. It’s a direct fit component which means you can easily install it yourself without the help of a mechanic.
The converter is also engineered to keep your check engine light off which helps eliminate emissions codes. MagnaFlow manufactures converters with high quality materials to ensure durability and this one has a 50 000 mile warranty to ensure stable service life.
MagnaFlow’s catalytic converter improves your car’s overall performance by increasing horsepower and protecting other components of your car. It eliminates foul exhaust smells & prevents pollutants from entering your engine & the atmosphere around you.
Pros
- Optimizes efficiency
- Used for petrol and diesel applications
- Robust design
Cons
- Not CARB compliant
8. FlowMaster 2230125 Catalytic Converter
Editor’s Rating:
With its excellent flow characteristic, the FlowMaster converter is able to actively eliminate all harmful emissions and gas pollutants from the exhaust system.
Key Features
The FlowMaster is made with robust stainless steel construction with internal substrates made with ceramics. It’s a three-way style converter for maximum oxygen flow. It has a round shaped body with the dimensions of 10,50″ X 4″.
It has a slip-fit inlet and outlet connection type with diameters of 2,5″. The FlowMaster catalytic converter is compatible with cars that have an engine capacity of 5,9L and a maximum weight of 6000lb.
Why Use the FlowMaster Converter?
The FlowMaster Universal fit catalytic converter is designed to meet and even exceed EPA requirements & is suitable for a wide variety of applications. The high quality converter is manufactured in the USA using high quality materials to ensure long service life.
All the precious materials and substrate combinations are engineered to perfection to eliminate MIL codes. The FlowMaster Catalytic converter is a universal component which means you may need a professional to help you with the installation. It may need additional modifications such as welding and cutting.
The FlowMaster 2230125 catalytic converter improves your car’s overall performance and prevents exhaust fouling. It also protects the other components in your vehicle from harmful pollutants. Unfortunately, it’s not CARB certified but it does have an official EPA stamp which is standard in all 49 States.
Pros
- Robust construction
- Keeps the MIL light off
- Excellent flow
Cons
- May be difficult to install
9. MagnaFlow 447206 Universal Catalytic Converter
Editor’s Rating:
The direct fit component means it’s of OEM standards. An OEM component means you don’t need any additional modifications done such as welding or cutting as it’s easy to install without professional assistance.
Key Features
MagnaFlow’s catalytic converter has a clamshell structure made from durable stainless steel with dimensions of 5,5″ x 9″. The internal substrates are made with ceramics for maximum flow. It has an inlet and outlet pipes with a diameter of 2,5″ each which is standard.
There are no oxygen sensor locations and no air tubes but the seam is welded close to the body of the converter for a tight & robust fit. The MagnaFlow 447206 series is suitable for both diesel and petrol applications.
Why Use MagnaFlow Converters?
It’s difficult to find a catalytic converter that meets the standards of the California Air Resources Board (CARB) which makes this a versatile component. It will exceed EPA requirements so it can be used in myriads of applications in all 50 states.
The certified CARB component is ideal. It maximizes the conversion of harmful pollutants which contributes to the protection of other components in your vehicle. The robust construction also ensures the longevity of the converter’s service life.
MagnaFlow catalytic converters are known to improve the performance of your vehicle by increasing acceleration and eliminating MIL error codes. The converter reduces fouling and keeps your exhaust from emitting pollutants into your engine & into the air around you.
The MagnaFlow brand manufactures superior catalytic converters and exhaust technologies. Each component is made with exact OEM specifications to keep your engine check light off.
Pros
- CARB certified
- For petrol and diesel applications
- Premium quality
Cons
- Installation may be difficult for some
10. Pontiac G6 Catalytic Converter
Editor’s Rating:
It’s designed to fit all post-OBDII models which means any applications from 1998 and newer. It’s one of the best OEM standard component brands on the market.
Key Features
Pontiac’s G6 catalytic converter is made with a strong stainless steel outer shell for maximum durability. The internal substrates are made with premium precious metals for efficient flow. Durable OE flanges are designed for easy installation and the bolts fit existing exhaust systems.
The honeycomb internal construction is designed to allow the catalytic converter to fully react to exhaust gasses without compromising the airflow. The increase in flow reduces back pressure and increases performance.
This component comes with a gasket and hardware so you can easily install the catalyst into your vehicle. It’s not CARB compliant but it does have an official federal EPA stamp which meets emission standards in 49 states; not in California though.
Why Use the Pontiac Converter?
The Pontiac catalytic converter is designed with strong materials to ensure a long service life which contributes to its 50 000 mile manufacturing warranty.
It’s a high flowing catalytic converter which contributes to efficient and cleaner exhaust gasses. The Pontiac converter removes restrictions that can impede your car’s overall performance. It also eliminates MIL error codes and ensures the check engine light stays off.
The Pontiac converter reduces exhaust emissions and prevents foul smells coming from the exhaust. It also prevents pollutants from entering other components in your car and protects the overall environment.
This catalytic converter fits well into any application with no additional modifications, such as cutting or welding, needed. It also comes with all the hardware needed for installation. It’s advised that you insert a gasket to prevent exhaust leakage.
Pros
- Reduces fouling
- Direct fit
- Exceeds EPA requirements
Cons
- Shipping services are not ideal
Guide to Buying the Best Catalytic Converters
Federal or CARB Converters
Before purchasing a catalytic converter you’ll need to know what kind of emission system your vehicle is manufactured with. Your catalytic converter has to adhere to either CARB or Federal regulations. You can find out by popping the hood of your car to find the emissions sticker.
The sticker will either be located directly on the underside of your hood or near the firewall area behind the engine. Federal standards for catalytic converters are in line with EPA (Environmental protection Agency) standards.
The California Air Resources Board (CARB) is stricter on their regulations. CARB requires more precious metals and rigorous testing which is why they cost more than EPA catalytic converters. To see which converter you need, check the following:
- Your converter will be CARB compliant if your vehicle was originally sold in the state of California.
- It may or may not be CARB compliant if your vehicle was sold in one of the other 49 US states. Check your state’s DMV site to see if they follow California emission standards.
- If your catalytic converter is CARB compliant it will be stamped with a certification or it will be labeled accordingly on the shell. The stamp will include the part number, installation directions, CARB approval number and the manufacture date.
Why CARB Converters?
CARB is stricter on their regulations because they are more serious toxins being released into the atmosphere. Since its establishment in the 1960s CARB has made it its mission to protect Americans from harmful toxins.
The CARB regulations were formed in response to Los Angeles’ severe smog problems. They subsequently set higher regulations to help control vehicle emission-based pollutants to reduce the effects of GHG (greenhouse gasses). And so each person can aid in reducing their carbon footprint.
Although the regulations are based in California other states follow CARB standards. The states that currently follow CARB regulations are as follows:
- Arizona
- California
- Connecticut
- Maine
- Maryland
- Massachusetts
- New Jersey
- New Mexico
- New York
- Oregon
- Pennsylvania
- Rhode Island
- Vermont
- Washington
- District of Columbia
What is an EFN?
EFN stands for Engine Family Number. It’s the number given to your specific engine which you’ll need in order to find the correct catalytic converter for your vehicle. You’ll also need to know the following:
- Manufacture year
- Model number
- Engine type
- Transmission type
- Sub model
You’ll find your EFN number on the VECI (vehicle emissions control information) label. The location of the label all depends on the model and make of your vehicle. The label is most commonly located under the hood of your car or on the fender.
If you’re not sure where to find your EFN number follows these steps:
- Pop the hood of your vehicle and prop it open.
- Search for your emission sticker.
- Locate the EFN number on the sticker
- Write down the EFN number and use it as a reference when you purchase your catalytic converter.
When to Change your Catalytic Converter
Typically a catalytic converter can last up to 10 years and maybe even longer. You can change your converter when you need to as there is no set maintenance time for these components.
The most common symptoms of a damaged or old catalytic converter include reduced acceleration, the smell of sulfur or a foul smell from the exhaust and excessive heat under the vehicle. You will also notice a drop in gas mileage and you’ll experience frequent stalling.
If you don’t accelerate when pushing your foot down on the accelerator you could have a clogged catalytic converter. If you have a clogged catalytic converter it could potentially damage your engine because of the exhaust back pressure.
Your oxygen sensor will also fail as the cause of poor fuel and air mixture will result in too much or too little oxygen entering into the exhaust system. If there’s insufficient oxygen entering the exhaust system there won’t be enough oxygen to react with the carbon monoxide and hydrocarbons during the oxidation catalyst stage.
Too much oxygen produced will cause overheating which will melt and clog the catalytic converter in your vehicle.
Take note that faulty spark plugs and damaged exhaust valves can also cause catalytic converter problems. If you’re experiencing acceleration problems and backfiring on the exhaust or any of the above mentioned points, you should have your catalytic converter replaced immediately.
How to Maintain Your Catalytic Converter
In order to preserve your catalytic converter, you’ll need to maintain it regularly. There are products out there that you can put into your catalytic converter to clean it. You don’t necessarily have to go to a mechanic to have your converter cleaned. Follow these simple steps to clean your converter.
Step 1
Ensure your vehicle is parked on a hard flat surface. Open the hood of your car and lift the prop rod. Use the prop rod to keep the hood of the car open while you work. Put on protective gloves and eyewear before you start working.
Step 2
Use the correct sized wrench to remove the bolts holding the converter in place. Place the bolts in a safe place until you need to use them again. Remove the catalytic converter from your exhaust system.
Step 3
Inspect the catalytic converter for any damages. Move it around and listen for any sounds that could mean there are loose parts.
Step 4
Clean your converter by wiping away any residue using a clean cloth. Use a power washer to remove any built-up debris. Force water into the inlet and outlet pipes to clean them thoroughly.
Step 5
Allow the catalytic converter enough time to dry before installing it back into the exhaust system.
Cleaning the Converter Without Removing It
It is possible to clean a catalytic converter without removing it from the vehicle. There are many cleaning aids on the market such as OXICAT that can unclog your converter. Just note that converter cleaning aids won’t always clear out components if they’re damaged.
Check your converter for any cracks or damaged parts before clearing it out. To clean the converter all you have to do is put some of the cleaning aid into your fuel tank before you go for a drive. The cleaning product will clean your O2 sensors as well as the entire exhaust system.
Final Thoughts
As you can see there is a lot to learn about catalytic converters. If you feel it’s time to replace your catalytic converter try one of the above mentioned brands. They’re all trusted manufacturers that make their converters with quality materials to ensure maximum performance for your car.
It would seem MagnaFlow and the Walker brands are the top manufacturers on the market at the moment. So if you’re looking for a catalytic converter that’s not going to be difficult to install and won’t break after a few miles, MagnaFlow and Walker components are for you.
To minimize your vehicle’s footprint and to avoid legal actions make sure your car has a proper certified catalytic converter according to your state’s requirements. It won’t only protect other components in your car but it will also protect the environment from pollutants.
Improve the performance of your vehicle and contribute to eliminating emissions by purchasing one of the above premium quality catalytic converters.
