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Author Topic:   Header building
posted October 05, 2004 07:29 PM
I am building a set of headers for my street car right now, and I have a question. They are 1 5/8" primaries 36" long. My question is how much tolerance can I live with in the length of each tube and still get good results? This is on a 302 cubic inch motor turning about 6000 rpms. This is my first go at building headers, so I am looking for a little insight first. Thanks.


posted October 05, 2004 08:54 PM
on a street car i wouldn't worry about it too much. what are you trying to do? get a bigger ticket?

posted October 06, 2004 05:30 AM
Dode, if my memory serves me correctly, you won't be able to notice any difference if you're slightly off in length. The key is for them to connect in the same spot, unless you're building a 4-2-2-1 y-pipe setup. I have seen where people will vary the lengths of pipes intensionally to achieve a broader torque band, vs. one certain power range. I'm sure you already are aware of this, but the length of your primaries, secondary length/location will dictate your power band for your engine. Hope this helps.

posted October 06, 2004 10:29 AM
Here's a couple of pointers. Get a chain type exh. pipe cutter. they work slick, don't fully weld anything until you're happy with how it fits. Use .024 type wire if using mig welder. Fit is most times more important than length. Power diff will be small even if they're off a bit. Use U bends in the size you need they help allot. Build each pipe towards the collector. Have the collector mocked into place to visualize where your headed. Have stuff like spark plugs in, leave room for wires, starter, oil pan & filter etc. when you go to finish welding them, go slow they will warp and cause fit problems. Have fun!!!