Header Reducers

Your headers end in one size, and the rest of your exhaust is a different size. Looks like you need some header reducers!

Since lap joints are easier to deal with than...

Your headers end in one size, and the rest of your exhaust is a different size. Looks like you need some header reducers!

Since lap joints are easier to deal with than butt joints, it's ideal to have the outside diameter of the pipe coming off the collectors fit within the inside diameter of the exhaust pipe. Header reducers (sometimes called collector reducers) usually have a flange on one end, to connect to the header, and the other end is made to slip fit into your exhaust system. From there, it's a simple matter to clamp the joint together, or simply weld it.

Summit Racing Equipment makes it easy to find the reducer you...

Your headers end in one size, and the rest of your exhaust is a different size. Looks like you need some header reducers!

Summit Racing Equipment makes it easy to find the reducer you need. You can filter the results below by collector diameter, outlet diameter, and even material and finish! If you need an exhaust sensor bung, you can filter those out, too.

If you need to change pipe sizes further downstream, Summit also carries exhaust pipe adapters and reducers to help you assemble the perfect custom system. For more information and advice on exhaust component sizing, check out this article and video on our blog.

Top Brands

Never settle for parts from third-party resellers! You can shop with confidence at Summit Racing Equipment, because we only partner with trusted manufacturers. Choose your header reducers from proven brands like Hedman Hedders, Dynomax Performance, Hooker Headers, Flowmaster, Kooks Headers, Patriot Exhaust, Sanderson Headers, JBA Headers, Pypes Performance, and many more.

Showing In Stock Items. Show All 31 Items.

Individual Parts

Part Groups

Results 1 - 25 of 30

Hedman Oxygen Sensor Reducers with 2.5 Inch Outlet 21142

Hedman Oxygen Sensor Reducers with 2.5 Inch Outlet 21142

Header Reducer, 3-Bolt Flange, 3.0 in. Inlet, 2.5 in. Outlet, Oxygen Sensor Fitting, Steel, Each

Part Number: HED-21142

4.28 out of 5 stars ( 18 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Summit Racing™ Exhaust Reducers with 2.5 Inch Outlet SUM-626102

Header Reducer, with Oxygen Sensor Bung, 3-Bolt Flange, 3 in. Inlet, 2.5 in. Outlet, Steel, Painted, Each

Part Number: SUM-626102

4.33 out of 5 stars ( 3 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Oxygen Sensor Reducers with 2.5 Inch Outlet 21143

Oxygen Sensor Reducer; Tube Size 2.5 in.; Collector Size 3 in.; w/Ball And Socket Flanges; Mild Steel

Part Number: HED-21143

4.56 out of 5 stars ( 9 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Oxygen Sensor Reducers with 3 Inch Outlet 21133

Header Reducer, with Oxygen Sensor Bung, 3-Bolt Flange, 3 in. Inlet, 3 in. Outlet, Steel, Painted, Each

Part Number: HED-21133

4.67 out of 5 stars ( 15 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Oxygen Sensor Reducers with 2 Inch Outlet 21106

Header Reducer, with Oxygen Sensor Bung, 3-Bolt Flange, 2.5 in. Inlet, 2 in. Outlet, Steel, Natural, Each

Part Number: HED-21106

Not Yet Reviewed

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Oxygen Sensor Reducers with 3 Inch Outlet 22126

Header Reducer, with Oxygen Sensor Bung, 3-Bolt Flange, 3.00 in. Inlet, 3.00 in. Outlet, Stainless Steel, Natural, Each

Part Number: HED-22126

3.75 out of 5 stars ( 4 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Oxygen Sensor Reducers with 2.25 Inch Outlet 21126

Header Reducer, 3-Bolt Flange, 2.5 in. Inlet, 2.25 in. Outlet, Oxygen Sensor Fitting, Steel, Each

Part Number: HED-21126

3.0 out of 5 stars ( 8 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Patriot Oxygen Sensor Reducers with 2.5 Inch Outlet H7233

Collector Reducers, 3-Bolt, 3 in. to 2.5 in., O2 Sensor Bungs, Gaskets, Fasteners, Pair

Part Number: PTE-H7233

3.75 out of 5 stars ( 4 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Oxygen Sensor Reducers with 2.25 Inch Outlet 21107

Header Reducer, with Oxygen Sensor Bung, 3-Bolt Flange, 3 in. Inlet, 2.25 in. Outlet, Steel, Natural, Each

Part Number: HED-21107

4.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Oxygen Sensor Reducers with 3 Inch Outlet 21134

Header Reducer, Ball/Socket Flange, 3 in. Inlet, 3 in. Outlet, Oxygen Sensor Fitting, Steel, Each

Part Number: HED-21134

3.88 out of 5 stars ( 8 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Patriot Oxygen Sensor Reducers with 2.25 Inch Outlet H7232

Collector Reducers, 3-Bolt, 2.50 in. to 2.25 in., O2 Sensor Bungs, Gaskets, Fasteners, Pair

Part Number: PTE-H7232

Not Yet Reviewed

Estimated Ship Date: May 5, 2026 if ordered today

...Loading

Estimated Ship Date: May 5, 2026 if ordered today

Hedman Oxygen Sensor Reducers with 2.25 Inch Outlet 21117

Header Reducer, Ball and Socket Flange, 3 in. Inlet, 2.25 in. Outlet, Steel, Painted, Each

Part Number: HED-21117

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Summit Racing™ Exhaust Reducers with 3 Inch Outlet SUM-626101

Header Reducer, with Oxygen Sensor Bung, 3-Bolt Flange, 3 in. Inlet, 3 in. Outlet, Steel, Painted, Each

Part Number: SUM-626101

2.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Summit Racing™ Exhaust Reducers with 3 Inch Outlet SUM-626100

Header Reducer, Ball/Socket Flange, 3 in. Inlet, 3 in. Outlet, Oxygen Sensor Fitting, Steel, Each

Part Number: SUM-626100

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Summit Racing™ Exhaust Reducers with 2.25 Inch Outlet SUM-626103

Header Reducer, with Oxygen Sensor Bung, 3-Bolt Flange, 2.5 in. Inlet, 2.25 in. Outlet, Steel, Painted, Each

Part Number: SUM-626103

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Summit Racing™ Exhaust Reducers with 2.5 Inch Outlet SUM-626104

Header Reducer, Ball/Socket Flange, 3 in. Inlet, 2.5 in. Outlet, Oxygen Sensor Fitting, Steel, Each

Part Number: SUM-626104

1.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Header Reducers with 2.25 Inch Outlet 21108

Header Reducer, 3-Bolt, 4-Bolt, Universal Flange, 3 in. Inlet, 2.25 in. Outlet, Steel, Natural, Each

Part Number: HED-21108

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

JBA Performance Exhaust Header Reducers with 2.5 Inch Outlet 1650-1ST

Header Starter Tubes, Ball and Socket, 2-Bolt Flange, 409 Stainless Steel, 2.5 in. Diameter, O2 Bungs, Pair

Part Number: JBA-1650-1ST

4.6 out of 5 stars ( 5 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Flowtech Header Reducers with 2.25 Inch Outlet 10105FLT

Header Reducers, 3-Bolt Flange, 2.5 in. Inlet, 2.25 in. Outlet, O2 Bung, Steel, Natural, Pair

Part Number: BIG-10105FLT

4.67 out of 5 stars ( 3 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Flowtech Header Reducers with 2.5 Inch Outlet 10110FLT

Header Reducers, 3-Bolt Flange, 3 in. Inlet, 2.5 in. Outlet, Steel, Natural, Pair

Part Number: BIG-10110FLT

3.67 out of 5 stars ( 9 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

JBA Performance Exhaust Header Reducers with 2.5 Inch Outlet 31650-1ST

Header Starter Tubes, Ball and Socket, 2-Bolt Flange, 304 Stainless Steel, 2.5 in. Diameter, O2 Bungs, Pair

Part Number: JBA-31650-1ST

Not Yet Reviewed

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Stainless Works Reducers with 3 Inch Outlet HCA33O2

Collector Adapter 3" inlet 3" outlet with O2 bung

Part Number: STW-HCA33-O2

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Hedman Header Reducers with 2 Inch Outlet 21116

Header Reducer, Ball and Socket Flange, 2.5 in. Inlet, 2 in. Outlet, Steel, Painted, Each

Part Number: HED-21116

4.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Stainless Works Reducers with 2.5 Inch Outlet HCA32.5O2

Header Reducers, Collector Reducers, 3-bolt Flange, 3.000 in. Collector Diameter, 2.500 in. Reducer Outlet Diameter, Stainless Steel, Natural, Each

Part Number: STW-HCA32-5O2

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 4/13/2026 if shipped by air

...Loading

Estimated Ship Date: Monday 4/13/2026 if shipped by air

Stainless Works Reducers with 2.5 Inch Outlet HCA3.52.5O2

HEADER COLLECTOR ADAPTER

Part Number: STW-HCA3-52-5O2

Not Yet Reviewed

Estimated Ship Date: Jun 15, 2026 if ordered today

...Loading

Estimated Ship Date: Jun 15, 2026 if ordered today

Page 1 of 2
Next