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Compact 2.5 Inch Oval Muffler in T304 Stainless for Custom Performance Exhaust Builds
The KO250-12 is a 2.5 inch oval weld on muffler with a 12 inch body, built from T304 stainless steel for performance exhaust fabrication on vehicles running 2.5 inch exhaust tubing. The oval cross section is the defining advantage of the KO250-12 for builders working under vehicles with limited ground clearance or undercarriage packaging constraints. Where a round muffler body of equivalent internal volume would stand taller and create clearance issues with the floor pan or spare tire well, the oval profile fits into tighter spaces while delivering the same flow performance and sound attenuation characteristics.
With a 2.5 inch inlet and outlet, this muffler is a direct fit for exhaust systems built around the 2.5 inch pipe diameter common on many V8 muscle cars, pony cars, and sports cars. T304 stainless steel construction ensures the muffler resists the corrosion and thermal cycling that deteriorate lesser materials over years of use. The weld on design creates a permanent connection that does not loosen over time the way band clamp connections can. Whether you are building a complete custom exhaust system or fabricating a replacement for a worn out muffler in an existing 2.5 inch system, this muffler delivers Kooks quality in a versatile universal package.
Key Features
- 2.5 inch inlet and outlet for 2.5 inch exhaust system compatibility
- 12 inch body length for effective noise attenuation
- Oval body profile for improved ground clearance versus round mufflers
- T304 stainless steel construction for durability and corrosion resistance
- Weld on installation for a permanent, leak free connection
- Universal fitment for custom fabrication applications
What's Included
- 1 x 2.5 inch oval weld on muffler with 12 inch body
Specifications
| Specification | Detail |
|---|---|
| Part Number (MPN) | KO250-12 |
| UPC | Contact us for UPC |
| Inlet Diameter | 2.5 inch |
| Outlet Diameter | 2.5 inch |
| Body Shape | Oval |
| Body Length | 12 inch |
| Material | T304 Stainless Steel |
| Installation Type | Weld On |
| Fitment | Universal |
Frequently Asked Questions
What exhaust pipe size does this muffler fit?
This muffler has 2.5 inch inlet and outlet connections for integration into 2.5 inch exhaust systems via weld on installation.
What is the advantage of the oval body over a round muffler?
The oval body has a reduced height compared to a round muffler of similar internal volume. This lower profile is useful on vehicles where ground clearance or body clearance under the car is a limiting factor.
How is this muffler installed?
This muffler is welded into the exhaust system. Both the inlet and outlet ends are welded to adjacent 2.5 inch exhaust tubing for a permanent connection.
What material is used in this muffler?
The muffler is constructed from T304 stainless steel, which provides strong resistance to rust, road salt, and the thermal stresses of a performance exhaust environment.
How long is the muffler body?
The body is 12 inches long. This dimension affects the internal volume of the muffler and its sound attenuation level.
Can I use this muffler on a single exhaust system?
Yes. This is a universal single muffler and can be used in single or dual exhaust configurations. For dual exhaust, two units would be required.
Is this muffler suitable for a turbocharged build?
Yes. T304 stainless construction handles the higher exhaust temperatures and pressures of forced induction applications, and the 2.5 inch pipe size is appropriate for many turbocharged engine setups.
Can I use clamps instead of welding?
Welding is the recommended installation method. Band clamps can be used for temporary fitment during fabrication, but a welded installation is more reliable for permanent use.
Is this muffler sold individually or in pairs?
This muffler is sold as a single unit. Order two for a dual exhaust system.
Installation Instructions
- Allow the exhaust system to cool before beginning.
- Plan the muffler location, accounting for the 12 inch body length and clearance to undercarriage components at the oval body height.
- Cut the 2.5 inch exhaust tubing at the inlet and outlet positions.
- Slide the muffler into position with the inlet toward the engine.
- Confirm that the oval body clears the floor pan, spare tire well, and all adjacent components at ride height.
- Tack weld at multiple points to verify alignment before completing full welds at both connections.
- Use T304 compatible filler material for TIG welding.
- Inspect for exhaust leaks after first startup.
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.
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