Universal Catalytic Converters

Does your exhaust system need a catalytic converter that can be welded into a custom-built or modified pipe? Universal catalytic converters have no vehicle-specific flanges or brackets. They are for you if you adapt the piping, length and position yourself in your project.

What a universal catalytic converter does

The catalytic converter converts some of the harmful substances in the exhaust gas before it leaves the car. A universal model is typically supplied as a housing with pipe inlets and outlets of a specific diameter and must be welded or clamped into the system. If you would rather avoid fabrication, direct-fit catalytic converters can be an alternative, and in the parent category for catalytic converters you can see both types.

How to choose a universal catalytic converter

• Pipe diameter: It must match your system. For example, MagnaFlow is available here in 2.00, 2.25, 2.5 and 3 inches.
• Cell count and length: For example, Kooks Headers offers a universal 3-inch catalytic converter with 400 cells and a length of 7.5 inches. Cell count, length and coating affect both back pressure and cleaning efficiency, so size alone does not determine the result.
• Air connection: Some variants have a port for secondary air, which is only relevant if the car has that system.
• Approval: Some product names refer to regulations in other countries. Whether the part can be approved for vehicle inspection in Denmark depends on the product and the car, and any E-mark must be checked for the specific part number.

Installation and maintenance

Position the catalytic converter so that the lambda sensors and heat shield fit, and make sure the joints are tight. An engine that runs rich or misfires can cause overheating and damage the catalytic converter. In this category you will also find brands such as Flowmaster, SLP and Weapon R.

Frequently asked questions

Should I choose a universal or a direct-fit catalytic converter?

A universal catalytic converter requires welding or fabrication, but gives you freedom in positioning and pipe routing. A direct-fit model is made for a specific car and is typically installed without modifying the system.

Can a universal catalytic converter be approved for vehicle inspection?

That depends on the specific product and your car. Check whether the part number has the necessary approval, such as an E-mark, and that the emission values meet the requirements for the car.

What does the cell count of a catalytic converter mean?

The cell count indicates how densely the channels in the catalytic converter's substrate are packed. It typically affects both back pressure and cleaning efficiency, but the result also depends on length, coating and the engine's needs.