Kooks Universal 2.5 Inch GREEN Catalyst 7.5 Inch Length

Free Flowing 2.5 Inch EPA Certified Cat for Street Performance Exhaust Builds

The GE-90148 is a universal 2.5 inch GreenCats catalytic converter with a 7.5 inch body length, built to deliver genuine emissions compliance without choking flow on modified street cars. Kooks designed the GE-90148 for performance exhaust systems where a 2.5 inch pipe diameter is the standard, including many V8 muscle car and sports car applications running factory or slightly enlarged exhaust tubing. The T304 stainless steel body and platinum coated high output substrate give you durability and efficient catalyst light off in a compact package sized for tight exhaust routing.

At 7.5 inches of body length, this converter fits into exhaust routing where a longer cat body would create clearance problems. The 2.5 inch inlet and outlet connections make it a direct drop in for 2.5 inch exhaust systems via weld on installation. EPA certification confirms this converter meets federal emissions standards for 49 state street use, making it appropriate for street driven vehicles outside of California. For builders assembling a complete high performance exhaust from scratch, or replacing a failed cat in an existing 2.5 inch system, this converter is a straightforward choice with Kooks quality behind it.

Key Features

• Universal 2.5 inch inlet and outlet for broad exhaust compatibility
• 7.5 inch body length for applications with tighter routing clearance
• EPA certified for 49 state street use
• High output GreenCats substrate rated for performance applications
• T304 stainless steel body construction
• Platinum coated substrate for fast catalyst light off
• Weld in installation for a permanent, leak free connection
• Not for sale or use in California (not CARB certified)

What's Included

• 1 x this converter universal 2.5 inch GreenCats catalytic converter

Specifications

Frequently Asked Questions

What pipe diameter is required for this converter?
This converter is sized for 2.5 inch exhaust systems. Both the inlet and outlet measure 2.5 inches for direct weld in installation into 2.5 inch tubing.

How long is the body of this converter?
The converter body is 7.5 inches long, making it a compact option suitable for builds where space between other exhaust components is limited.

Is this converter legal for street use?
This converter carries EPA certification and is street legal in 49 states. It is not CARB certified and is not legal for sale or installation in California.

Does this converter require welding to install?
Yes. This is a universal weld in converter. A professional exhaust fabricator should cut the exhaust pipe and weld this converter into position at both the inlet and outlet.

Will this converter restrict flow compared to a straight pipe?
All catalytic converters create some backpressure relative to open pipe. The GreenCats high output substrate is engineered to minimize this restriction compared to OEM replacement cats, making it appropriate for performance applications.

Can I use this converter on a turbocharged vehicle?
Yes. The GreenCats substrate is rated for performance and forced induction applications, including turbocharged builds that produce higher exhaust temperatures.

Is this sold as a single unit or a pair?
This converter is sold as a single unit. Dual exhaust V8 builds would require two converters.

What material is the converter body made from?
The body is constructed from T304 stainless steel, providing excellent resistance to corrosion and thermal fatigue over extended service life.

Does installing this converter require a tune?
If installing downstream of long tube headers or in conjunction with other engine modifications, an ECU tune is recommended to optimize fueling and prevent false O2 sensor codes.

What is the flow direction for installation?
Install this converter with the inlet (marked end) toward the engine and the outlet toward the rear of the vehicle to ensure proper catalyst function.

Installation Instructions

This converter is a universal weld in catalytic converter. Follow these general steps for proper installation:

1. Allow the vehicle exhaust system to cool completely before beginning work.
2. Mark the cut location in the exhaust pipe where this converter will be inserted, accounting for the 7.5 inch body length plus weld joint allowance.
3. Cut the exhaust tubing at the marked locations and deburr the cut ends.
4. Slide this converter into position, ensuring the inlet faces the engine and the outlet faces the rear.
5. Check clearance to the floor pan, frame, and any heat sensitive components before welding.
6. Tack weld at multiple points to confirm alignment, then complete full circumference welds at both connections.
7. Use filler compatible with T304 stainless steel for TIG welding, or a suitable MIG wire for MIG welding.
8. Inspect all welds for porosity or gaps before returning the vehicle to service.

Prop 65 Warning

WARNING: This product can expose you to chemicals including Chromium and Nickel, which are known to the State of California to cause cancer, birth defects or reproductive harm. For more information go to www.P65Warnings.ca.gov.