GMC G25 Header Reducers

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GMC G25

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Year

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Make

Model

G25

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3-Bolt

3-Bolt Ball and Socket

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93 products

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GMC G25

Products

Hedman Hedders |

#41821110

Hedman Hedders 21110 3 Inch Header Reducers 2-1/2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$45.48

/pair

Hedman Hedders |

#41821114

Hedman Hedders 21114 3 Inch Ball-Style Header Reducers 2-1/4 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt Ball and Socket

$33.39

/pair

Hedman Hedders |

#41821116

Hedman Hedders 21116 2-1/2 Inch Ball-Style Header Reducer 2 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt Ball and Socket

$25.12

/each

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 2.5/2.0-in SS

Speedway Motors |

#9302512

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 2.5/2.0-in SS

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$110.99

/pair

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/2.5-in SS

Speedway Motors |

#9302515

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/2.5-in SS

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$124.99

/pair

Tuning Tips after Header Installation

Making the switch from manifolds to headers is a popular performance upgrade, but it may take more than just bolting on the new part. We provide some tips and things to consider after you bolt on a new set of headers.

Exhaust System Header Wrapping

Whether you’re looking for performance improvements or heat reduction, if you decide to wrap your headers, we'll show you the benefits and possible precautions to take before you wrap your exhaust.

Hooker Header Installation Guide

Hooker headers are installed in a 1967 Pontiac Firebird for increased power and a boost in performance. See how to work through fitment of the steering box, clutch Z bar and starter.

Replacing GM Rear End Spherical Bushings

In this budget build, a GM rear end is upgraded in order to hold 400+ HP. See how spherical bushings are replaced in a used 8.5” GM 10 bolt rear end.

How to Install Side Detent Shifter for GM TH200, TH250, TH350, and TH400

Learn how to install a side detent shifter in a 1969 Chevy C10.

Hedman Hedders |

#41821155

Hedman Hedders 21155 2-1/2 Inch Header Collector Conversion Kit

Sold in Quantity:

Kit

Flange Style:

3-Bolt Ball and Socket

$199.99

/kit

-9%

Patriot Exhaust |

#447H7248

Patriot Exhaust H7248 Collector Reducers, 2.5" to 2.0" Outlet

Material Type:

Steel

Flange Style:

3-Bolt

$43.37

/pair

$47.71

Hedman Hedders |

#41821134

Hedman Hedders 21134 3 Inch Ball-Style Header Reducer 3 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt Ball and Socket

$25.57

/each

Hedman Hedders |

#41821104

Hedman Hedders 21104 3-1/2 Inch Steel Header Reducer 2-1/2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$38.99

/pair

Hedman Hedders |

#41821103

Hedman Hedders 21103 3 Inch Steel Header Reducer 2-1/2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$36.99

/pair

Patriot Exhaust |

#9307249

Patriot Exhaust H7249 Replacement Collector Reducer For H8014

Sold in Quantity:

Set

GTIN Code:

694342533175

$98.79

/pair

Patriot H7251 3" Diameter, 2 1/4" Outlet Collector Reducers

Patriot Exhaust |

#9307251

Patriot H7251 3" Diameter, 2 1/4" Outlet Collector Reducers

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$54.86

/pair

Hedman Hedders |

#41821122

Hedman Hedders 21122 3 Inch Ball-Style Header Reducers 2-1/4 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt Ball and Socket

$47.65

/pair

Hedman Hedders |

#41821156

Hedman Hedders 21156 3 Inch Header Collector Conversion Kit

Sold in Quantity:

Kit

Flange Style:

3-Bolt Ball and Socket

$165.26

/kit

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 2.5-inch

Speedway Motors |

#9302501

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 2.5-inch

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$69.99

/pair

Hedman Hedders |

#41821143

Hedman Hedders 21143 3 Inch Ball-Style Header Reducer 2-1/2 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt Ball and Socket

$23.92

/each

Hedman Hedders |

#41821101

Hedman Hedders 21101 2-1/2 Inch Steel Header Reducer 2 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt

$33.99

/each

Hedman Hedders |

#41821106

Hedman Hedders 21106 2-1/2 Inch Header Reducer w/O2 Bung 2 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt

$34.99

/each

Hedman Hedders |

#41821107

Hedman Hedders 21107 3 Inch Header Reducer w/O2 Bung 2-1/4 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt

$30.12

/each

Hedman Hedders |

#41821109

Hedman Hedders 21109 2-1/2 Inch Header Reducers 2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$42.59

/pair

Hedman Hedders |

#41821113

Hedman Hedders 21113 2-1/2 Inch Ball-Style Header Reducers 2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt Ball and Socket

$30.99

/pair

Hedman Hedders |

#41821115

Hedman Hedders 21115 3 Inch Ball-Style Header Reducers 2-1/2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt Ball and Socket

$33.99

/pair

Hedman Hedders |

#41821153

Hedman Hedders 21153 2-1/2 Inch Header Collector Conversion Kit

Sold in Quantity:

Kit

Flange Style:

3-Bolt Ball and Socket

$37.99

/kit

Hedman Hedders |

#41821142

Hedman Hedders 21142 3 Inch Header Reducer 2-1/2 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt

$27.99

/each

Hedman 22105 2-1/2 Inch Stainless Steel Header Reducers, Pair

Hedman Hedders |

#41822105

Hedman 22105 2-1/2 Inch Stainless Steel Header Reducers, Pair

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$178.99

/pair

Hedman Hedders |

#41822115

Hedman Hedders 22115 3 Inch Ball-Style Header Reducers 2-1/2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt Ball and Socket

$167.97

/pair

Hedman Hedders |

#41822123

Hedman Hedders 22123 2-1/2 Inch Ball-Style Header Reducers 2 Inch

Sold in Quantity:

Pair

Flange Style:

3-Bolt Ball and Socket

$172.92

/pair

Hedman Hedders |

#41822124

Hedman Hedders 22124 2-1/2 Inch Ball-Style Header Reducer 2 Inch

Sold in Quantity:

Each

Flange Style:

3-Bolt Ball and Socket

$93.62

/each

3-Bolt Exhaust Flange Collector w/ O2 Bung, 3.0/2.5-in SS

Speedway Motors |

#9302506

3-Bolt Exhaust Flange Collector w/ O2 Bung, 3.0/2.5-in SS

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$56.99

/pair

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.0/2.25-in

Speedway Motors |

#9302509

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.0/2.25-in

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$90.99

/pair

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.0/2.5-in

Speedway Motors |

#9302510

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.0/2.5-in

(1)

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$94.99

/pair

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/3.0-in

Speedway Motors |

#9302518

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/3.0-in

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$114.99

/pair

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/3.0-in SS

Speedway Motors |

#9302519

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/3.0-in SS

Gasket(s) Included:

Yes

Sold in Quantity:

Pair

Flange Style:

3-Bolt

$146.99

/pair

-9%

Patriot Exhaust |

#447H7238

Patriot Exhaust H7238 Collector Reducers, 3 Inch

(2)

Material Type:

Steel

Flange Style:

3-Bolt

$49.37

/pair

$54.31

Hedman Hedders |

#41821119

Hedman Hedders 21119 3 Inch Ball-Style Header Reducers 3 Inch

(1)

Sold in Quantity:

Pair

Flange Style:

3-Bolt Ball and Socket

$38.99

/pair

Hedman Hedders |

#41821152

Hedman Hedders 21152 3 Inch Header Collector Conversion Kit

Sold in Quantity:

Kit

Flange Style:

3-Bolt Ball and Socket

$39.99

/kit

Showing 1 - 36 of 93 results

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GMC G25 Header Reducers

Flange Style

Brand

Availability

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Price

Customer Rating

Products

Hedman Hedders 21110 3 Inch Header Reducers 2-1/2 Inch

Hedman Hedders 21114 3 Inch Ball-Style Header Reducers 2-1/4 Inch

Hedman Hedders 21116 2-1/2 Inch Ball-Style Header Reducer 2 Inch

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 2.5/2.0-in SS

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/2.5-in SS

Related Articles

Hedman Hedders 21155 2-1/2 Inch Header Collector Conversion Kit

Patriot Exhaust H7248 Collector Reducers, 2.5" to 2.0" Outlet

Hedman Hedders 21134 3 Inch Ball-Style Header Reducer 3 Inch

Hedman Hedders 21104 3-1/2 Inch Steel Header Reducer 2-1/2 Inch

Hedman Hedders 21103 3 Inch Steel Header Reducer 2-1/2 Inch

Patriot Exhaust H7249 Replacement Collector Reducer For H8014

Patriot H7251 3" Diameter, 2 1/4" Outlet Collector Reducers

Hedman Hedders 21122 3 Inch Ball-Style Header Reducers 2-1/4 Inch

Hedman Hedders 21156 3 Inch Header Collector Conversion Kit

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 2.5-inch

Hedman Hedders 21143 3 Inch Ball-Style Header Reducer 2-1/2 Inch

Hedman Hedders 21101 2-1/2 Inch Steel Header Reducer 2 Inch

Hedman Hedders 21106 2-1/2 Inch Header Reducer w/O2 Bung 2 Inch

Hedman Hedders 21107 3 Inch Header Reducer w/O2 Bung 2-1/4 Inch

Hedman Hedders 21109 2-1/2 Inch Header Reducers 2 Inch

Hedman Hedders 21113 2-1/2 Inch Ball-Style Header Reducers 2 Inch

Hedman Hedders 21115 3 Inch Ball-Style Header Reducers 2-1/2 Inch

Hedman Hedders 21153 2-1/2 Inch Header Collector Conversion Kit

Hedman Hedders 21142 3 Inch Header Reducer 2-1/2 Inch

Hedman 22105 2-1/2 Inch Stainless Steel Header Reducers, Pair

Hedman Hedders 22115 3 Inch Ball-Style Header Reducers 2-1/2 Inch

Hedman Hedders 22123 2-1/2 Inch Ball-Style Header Reducers 2 Inch

Hedman Hedders 22124 2-1/2 Inch Ball-Style Header Reducer 2 Inch

3-Bolt Exhaust Flange Collector w/ O2 Bung, 3.0/2.5-in SS

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.0/2.25-in

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.0/2.5-in

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/3.0-in

3-Bolt Exhaust Flange to V-Band Flange w/ O2 Bung, 3.5/3.0-in SS

Patriot Exhaust H7238 Collector Reducers, 3 Inch

Hedman Hedders 21119 3 Inch Ball-Style Header Reducers 3 Inch

Hedman Hedders 21152 3 Inch Header Collector Conversion Kit

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