Be Careful....
Yes, the diesel dragster header is one I built myself, and it was (note the word was) equal length and JetHot coated inside and out.
It actually lost heat energy more than the ATS manifold and adapter I am running now. The header was a good engineering exercise, I spend 30 hours building and $400 in parts and coating.
On the dyno, it overheated during a wastegate tuning session, and hit 1900 or so. No longer in good shape.
I really suggest a cast manifold for any serious power, and if you really want a header, go stainless, or inconel. Equal length? No real gain seen. I am building more headers for the dragster for a VG twin setup up, VG on the HP and VG on the LP, and another with a stupid big LP and VG HP... .
We will be testing it all after the truck drags... July 25.