Part 1-Hedman Header Dyno Weld up kit. Buying Parts

Headers are both an engine and trans/converter/chassis/application part. But I am listing them in Part 1- Buying Parts.
I decided to try the Hedman Dyno Weld up header kit for the Chrysler big block wedge engine. Hopefully this will reduce the amount of cutting/fitting/welding to make headers for this engine in my Daytona tube chassis drag race car. IMO, this application could use either the 2-1/4” tubes or 2-3/8” tubes. One will favor the RPM range just above torque peak, and the larger tubes could be used for peak top RPM horsepower.

As delivered, the tube lengths are about 40” using a tape measure inside the tubes. All tubes have a long length (~6”) from the head to the first bend (for dyno applications), so they can be shortened if desired for a car. Also, there is a long (~10”) straight section in each tube before the collector, so the overall desired length can be shortened even more. Therefore, these numbers should be considered the maximum tube lengths without extensions.

The Hedman catalog says the rear tube must be cut and rotated. As you can see the #7 tube is pointing away from the engine. It appears to be the same part as the #8 mandrel bent tube. But I expect to cut/fit/weld more to route in my car’s chassis and exit where I want.

I didn’t like the flanges that came with the Hedman kit. They were a little rough cut and the port didn’t match my heads. So, I had a local Laser Cutting shop make custom flanges for me to my specs. They are 3/8” thick and the opening is shaped like my ports, and sized for a 2-1/4” tube to be inserted and welded.