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Hedman Hedders 21110 Header Reducer Gasket Kit

Manufacturer

Hedman Hedders

<h3>Hedman Hedders: Over 70 Years of American-Made Exhaust Performance</h3><p>Few names carry as much weight in the hot rod and performance world as <strong>Hedman Hedders</strong>. Founded in 1954 by Bob Hedman, the company holds a unique distinction: <a href="/309-hedman-hedders-exhaust-header-5848">Hedman was the world's first mass producer of exhaust headers</a>, born from a grassroots passion for drag racing and engine performance. What started as Bob selling hand-welded exhaust tubes to fellow racers eventually grew into one of the most recognized brands in American performance manufacturing — and every header is still made in the USA.</p><p>Bob Hedman's origin story is the stuff of hot rod legend. As a teenager, he swapped a flathead V-8 into a Model A and never looked back. His early curiosity about exhaust flow led him to purchase the Equaflow exhaust business in 1954, rename it Hedman Muffler and Manufacturing, and pivot entirely to building &quot;hedders&quot; — the intentional misspelling a clever way to brand the product as uniquely his own. Demand from the drag racing community exploded almost immediately, and the company name was soon changed to Hedman Hedders to reflect what the brand had truly become.</p><h3>What Makes Hedman Headers Stand Apart</h3><p><a href="/309-hedman-hedders-exhaust-header-5848">Hedman exhaust headers</a> are engineered for performance, restoration, and engine-swap applications across GM, Ford, and MOPAR platforms. The lineup spans long-tube, mid-length, and shorty configurations, with designs tailored for everything from classic muscle cars and C10 pickups to modern LS swap builds. Headers are constructed from mandrel-bent primary tubing with laser-cut flanges, ensuring consistent fitment and leak-free performance — hallmarks of a brand that has refined its craft over seven decades.</p><p>One of Hedman's most enduring contributions to the industry is the HTC (High Temperature Coating) ceramic-metallic finish, a technology that <strong>Bob Hedman himself developed</strong> and that remains widely used by exhaust manufacturers to this day. Available in polished silver, satin black (Black-MAXX), and stainless variants, these coatings resist corrosion and withstand extreme heat, while also carrying their own multi-year factory warranty on top of Hedman's standard limited lifetime header warranty.</p><h3>A Complete Exhaust Ecosystem</h3><p>Beyond their flagship headers, Hedman supports a full exhaust installation ecosystem. Proper header installation often requires connecting the collector to the downstream exhaust system, which is where <a href="/309-hedman-hedders-exhaust-header-reducer-16774">Hedman exhaust header reducers</a> come in. Available in ball-and-socket and 3-bolt flange styles, these reducers are sold as matched pairs with all necessary hardware, making the transition from header collector to exhaust pipe clean and secure.</p><p>Sealing the system correctly is equally important. <a href="/309-hedman-hedders-exhaust-flange-5824">Hedman exhaust flanges</a> and gasket hardware are purpose-built to mate with Hedman header collectors, ensuring tight, leak-free joints that hold up under the thermal cycling of performance driving. For vehicles equipped with factory emissions systems, Hedman also offers parts that support <a href="/309-hedman-hedders-secondary-air-injection-check-valve-22222">secondary air injection</a> compatibility — many Hedman header configurations are offered with A.I.R. provisions built in, and associated check valve components help maintain emissions compliance on applicable builds.</p><h3>Built for GM, Ford, and MOPAR Enthusiasts</h3><p>Whether you're building a period-correct street machine, swapping in a modern LS engine, or extracting more power from a stock small-block, Hedman Hedders has a solution engineered specifically for your combination. Their engineering team continuously updates fitment data to accommodate new suspension components, steering upgrades, and chassis configurations — so builders get headers designed for real-world clearance, not just theoretical fit. For classic car restorers and serious performance builders alike, Hedman remains the standard by which American exhaust headers are measured.</p>

Part Number

21110
07/17/2036 8:28 PM
Sale Price

$42.33

In Stock (6)

delivery box

Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Hedman Hedders 21110 Header Reducer Gasket Kit provides everything needed to complete a professional header collector reducer installation. This complete kit eliminates the need to source components separately, ensuring proper sealing and secure mounting.

What's Included:

  • 2 reducer gaskets per package
  • Matching flanges for secure connection
  • All necessary mounting hardware

Designed to work with Hedman Hedders exhaust systems, this kit ensures a proper seal between header collectors and your exhaust system when using reducer pipes. The included gaskets help prevent exhaust leaks while the flanges and hardware provide a secure, vibration-resistant connection.

Products specifications

Bolts/Studs Included

Yes

Collector Attachment

3-bolt flange

Gasket Material

Paper

Oxygen Sensor Bung Included

No

Quantity

Sold as a pair.

Reducer Finish

Aluminized

Reducer Material

Steel

Reducer Outlet Diameter

2.5 in.

Very fast shipping

Awesome

My second order for the same rack for our new fleet pickup truck. I did not know what to expect with the first delivery. I was very satisfied and impressed with the quality for the price paid. The price on my second order within a month or two did increase approximately $12. I still feel this price is within reason. Of course we all like to pay less! The shipping time is adequate for the free delivery. I do recommend this rack. If the others in this line are as well build you will not go wrong with this brand. Thanks from the Glynn County Airport Commission Fleet Department.

Great site, user friendly!

Easy

Arrived timely, was the correct part.

So far so good. Now if the part fits it'll be great!!

Great prices on parts.

Autoplicity simply had the best prices available and everything was in stock to be shipped.

love the amazon sign in

Autoplicity leads the way ! Others take a lesson !! Great prices and excellent service !!!

No problems ordering a leak down tester from Autoplicity which had the lowest price and reasonable shipping charges. The item was well packaged and I would buy from them again.

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