Im gunna be building a header pretty soon for 263 straight eight using a Victory header flange. I was looking around their website and came across some pictures of customer built headers.. Are these headers twisted and wrapped around in this manner to keep the tube length the same? I've also read somewhere that this is because this header is "tuned". What exactly does "tuned" entail ??
For hot rods like ours, a tuned header really isn't going to make a hell of alot of diffrence. If we were really in a quest for every single last tiny bit of horse power, we wouldn't have six Strombergs on a Y block... The headers in the pic may or may not be equal length, but I think the guy built them that way cause they would look cooler than the regular way rather than to be perfectly tuned. Good luck, -Abone.
As one who builds headers for a living, I can tell you that this was done just for looks! And it's kind of cool. Exhaust air flow is laminar, and as such, every curve changes the flow of the exhaust. There is a lot of science that goes into a good race header and it is beyond the scope of what most people would be willing to learn or spend the time on for a Hot Rod. A tuned header means that the designer tuned the length of the tubes for a given RPM range based on Compression, cam timing, VE of the engine, Carburetor etc etc. Ideally every tube would end up the same length that is calculated by knowing all the engine information. But in reality, you can't build them all the same length and end up at one collector point, especially since the car and it's parts get in the way. So the builder has to compromise and that means bends and angles and this changes the flow characteristics of each tube. The best advice for a novice header builder is KISS - Keep It Simple Stupid! Do dome studying and figure out a good goal for primary diameter and length and then take the straightest paths to get there. This will give you the best you can hope for and should make good power. That example above would be out powered by a simpler, straighter design I would bet. There are exceptions to that, like the "Bag Of Snakes" 180° designs that were popular in Indy and Formula 1 back in the 60's but they had many hours of design and experimental work.
my sentiments exactly!! PS I built my first set of headers in 1967. No headers available for fender well exit 383 Chrysler in a 38 Chevy coupe.
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