At Hedman Hedders, it’s all about pride. Pride in what the company has achieved in the past and pride in what they are developing for the future of hot rod headers. When you visit their manufacturing facility in Whittier, California, it’s clear to even the most casual observer that Hedman Hedders cares about their reputation and the quality of their products. Awards are proudly displayed in large trophy cases and photos from racing’s greatest legends are lining the hallways.  Officially started in 1954, Bob Hedman had already been building headers for many racers looking to maximize their performance. With 60 years of experience behind them, Hedman has a lot to be proud of.

We wanted to stop by and take a look at the Hedman manufacturing facility in Whittier, California because it’s close to our own back yard and we had heard that major car collectors were still ordering Hedman Hedders for their collector cars in large quantities. Hedman Hedder have become a staple for many hot rod fanatics, which is no surprise given the research and development that goes into each style of header produced, but to have a half century’s worth of staying power with fickle A-list car collectors is nothing short of amazing.

How It’s Made

We had the idea to do a story on a set of Hedman Hedders from start to finish in order to show how Hedman has taken Henry Ford’s idea of mass production and incorporated the research and development into the process to expand product lines of the headers for quality fit in almost any engine bay with almost any aftermarket engine products. In essence, Hedman has found a way to offer a Hedman “custom” header at mass production prices.

"The stock of unbent tubing was low on this day," according to Hedman's Marc Lewis, "We are waiting for a shipment to come in," he added.

Mr October

We showed up to the Hedman factory and outlined the idea of following a set of headers from beginning to end in the manufacturing process. Hedman Hedder’s Director of Marketing, Marc Lewis liked the idea and took us to the factory floor where we began at the raw material area. Picking up the first order in the stack of daily orders, we saw a name that we immediately identified as one of the most recognizable car collectors in the Nation, Reggie Jackson.

The 20 foot sections of tubing are cut into individual header tubes at the first station.

So our tour began by following a selection of straight exhaust tubing that was eventually going to become a set of Hedman Hedders for a Gen I Camaro owned by Reggie Jackson. For an interesting story line, it looks like we made contact and it was heading back… back… back… toward the warning track and over the wall. Holy Cow! It’s a home run.

In The Beginning…

The first verse in the Hedman Hedder bible, Genesis verse 1.1, begins with, “In the beginning there was exhaust tubing, and exhaust tubing was with Hedman Hedders, and the exhaust tubing was Hedman Hedders.” Verse two continues by saying, “Hedman said let the headers fit correctly and make power. Car enthusiasts saw that the design was good, and so it was.”

This was our starting point, looking at the pallets of raw straight exhaust tubing in twenty foot sticks of various diameters. Marc Lewis, our tour guide for the day, apologized for the limited supply of tubing, which looked like a pretty good supply to us. According to Lewis, they were awaiting a shipment of tubing and normally there was three or four times this amount in the raw material area.

Doing a Jig

When the orders are processed, the correct diameter of tubing is pulled from the raw material area and cut down into individual pipe sections. For each header offered by the company, there are tube length specifications that have been carefully developed from vehicles that they are intended to be installed in. From the research and development phase of their header design, Hedman makes a “master” header which is used to develop a set of jigs that holds the headers in place during manufacturing. This process ensures there is minimal waste in the manufacturing process.

The tubing comes out of the bending machine with a series of precise complicated bends on each tube.

Lewis explained that the jigs are custom built by the company to ensure that each header falls within an exact tolerance. “A fraction of an inch or a degree off here or there could make a big difference in the final product. It could be the difference in a header fitting or not fitting in a customer’s collector car engine bay. We build the jigs with very tightly controlled tolerances so that each header is built as closely to the ‘master’ header as humanly possible.”

Getting The Bends

After the individual tubes are cut to length for the specific header design, the tube ends are shaped so that the bending machines can work with the tubes without difficulty. The tubes are placed into large carts by part number which identifies them for specific header design and placement.

The tubes then travel to the next phase where tube bending machines put the necessary bends in each header tube. The machines are operated by a computer program and almost fully automatic. The only assistance needed is a set of hands to put the unbent tube into the dies and remove the fully bent tube once the operation is done. Lewis explained that the company was in the process of changing over to all new equipment which was even more automatic.

Putting It All Together

When the bent tubing arrives at the next station, the appropriate header flanges and collector flanges are pulled from the shelves, along with the proper header jig. The entire header assembly is test fitted to ensure that everything is correct and the all of the materials to build a specific header are at the work station.

Each header tube is checked for fit before the end is heated up with a torch to anneal the metal. This not only removes stresses from the composition of the metal but it also makes the metal less brittle and easier to work with in the shaping process. The annealing process is a critical to ensure that the tube end does not crack or split when the metal is worked by stretching and shaping.

With the tube ends annealed, each tube is taken to a machine that shapes it for a snug fit in the header flange. This is actually a two step procedure where the first step angles the tube end for proper orientation in the flange and the second step which shapes the tube end to match the header flange and exhaust port on the cylinder heads.

While this process is going on, another station is working on the collector end of the header assembly. A three inch tube is stretched into a semi-square shape that will accommodate the four exhaust tubes as they meet at the collector. On the other end of the collector, a mounting flange is installed with a flare at the round end of the collector to promote a secure sealing surface when installed to the rest of the exhaust system in the vehicle.

Circular Welding

When the tube ends are perfectly shaped and the entire header is reassembled on the jig, it moves to the next station, where the tubes are welded to the exhaust flange and collector. Lewis explained the importance of using their heavy duty custom jigs and circular welding process, “the jigs are built so that they can be used at each station, including the welding station where the welder assembles and welds the tubes to the head flange, welds a collector star to the ends of the tubes, then tack welds the collector to the headers.  Once the welder finishes those steps, he sets them in the rack where they are taken to the circular welding station. Here the welder places the header on a turntable and finish welds the collector to the header. The rack helps to eliminate heat distortion and movement in the header tubes as the welder is using a circular welding technique that also helps to reduce tube distortion,” Lewis says. The welder then hangs the headers on a large rolling rack that is eventually moved to the header flange grinding station that utilizes belt sanders.

Once the welding is complete there is one final piece to add. The Hedman Hedder’s name plate is welded on the header assembly and sent over to the final quality control inspection.

Wrapping It All Up

The Quality Control department uses several techniques to ensure the the welds are complete and the tubes are sealed. Each seam and joint is inspected. A torch is used to spot any pin holes in the welds or bends and visual inspection of the entire assembly is conducted. Lewis explained the process, “the headers are sprayed down at the outside of the collector with water and the inspector heats the header with the flame to boil off the water, he is looking for any vapor from the evaporating water coming out the end of header collector opening. If vapor comes out the collector, then there is a leak.”

“Conversely, when he sprays the inside of the header collector and boils off the water, he is checking for vapor escaping out of the header through the collector welds. It is an old technique, but one of the most effective methods for detecting any leaks,” Lewis added.

If there are no problems, the header either goes to packaging where it will be boxed and ready for shipment or get additional treatment like protective or thermal coatings depending on the customer’s order.

Final Analysis

A good set of headers is not something that you can do at home in your garage. We’ve seen that Hedman Hedders are carefully developed on the vehicles that are intended to fit, with several different options for most aftermarket combinations. The headers are checked and rechecked several times through the process.  The amount of time and resources spent on development of these complex designs is far beyond what a DIY or fly-by-night operation can handle. A set of Hedman Hedders is as close to custom built as you can get and still have the convenience of an off-the-shelf part. If it’s good enough for Mr. October, then it’s a home run as far as we are concerned.