header flanges??

want to try and build some headers for my 241 hemi, what thickness material would be good to use for the flanges? should the tubes go through the flange or butt up against the outside of the flange? is there any problems with welding the thinner tube material to the thicker flange material? what material options exist for making "limefire" style headers, didn't a particular year torque tube get used for headers?? thanks-

 

I just some for the 350 buick off egay and they are 3/16" nice fit & quality too.

 

Quarter inch works fine - contrary to some who think thicker is better.
I've made several sets from 1/4" and no leakage problems.
And that's using either the hot rod aftermarket one piece high-temp paper gaskets, stock aluminum with asbestos-like innards as well as steel shim stock gaskets.

Make a point to use cold rolled for the flanges.
Hot rolled works, but cold rolled is easier to work with and makes a much nicer product.

The tubes do go through the flange.
For rectangular exhaust ports, squash the exhaust tubing in a vise so that it's close to the rectangular hole in the flange. Close enough to fit anyway.
After it's in - in the correct orientation - tack it in place and use a small ball peen hammer or the rounded pick end of a body hammer, heat the corners where the tubing doesn't quite fit the flange to a dull orange and tap - not bash, but tap - to shape.

We used to arc weld the tubing to the flange from the inside keeping most of the arc on the flange.
Some guys MIG them together using the same method.
I like to use a TIG for this joint as it's easier to control.

After the headers are built and welded together, run a fillet of brass (brazing) around the tubing/flange joint on the outside for reinforcement. Lotta race cars do this and it helps to prevent vibration induced cracks.
My 32's headers are brazed and TIG'd and no problems since 93.
If all the flux is removed, you can paint, jet coat or chrome over the joint.

One option for a Limefire header is to have a sheet metal shop roll up a cone for you.
It's less trouble for them to roll a cone to a general size at each end and you cut it to size than it is to have them roll an exact size.
Long as you get two basic tubes to match you're in business.

There are Limefire style kits, but if you're gonna build one for crying out loud don't just stick the primary tubes in at a 90 degree angle.
Works bad, looks worse - imho.
Make a point to build a flowing curve by using the inner part of a U-bend.

Not sure about the exact year torque tube preferred.
Check in (AV8) Mike Bishops book on <font color="blue"> How to Build a Traditional Ford Hot Rod </font>

Here's a somewhat self explanatory photo of how to build flanges.
As you can tell these are individual ones instead of the one-piece ones usually seen.

 

Here's the really easy way to set up headers.
Provided you like this style.
Shown mocked up on my 31.

The headers are for an SBC w/Brodix heads which have about the same port spacing as does the 455 Buicks I use.
As well as the tubing size is 1 7/8" which is the recommended size primary on all but the most full-race of Buick engines. Those call for 2" primaries.
(I believe this same kit is available for Fords - it's a Schoenfeld kit.)

If you're running an SBC or Ford life is easy.
It ain't too much more difficult for the 455 Buicks.
A short piece of U-bend to bring the primary up to match the 45 degree angle of the Buick exhaust port, some Buick flanges and you're in business.
Makes for a nice looking header.

As a smal fwiw - for the guys looking for a header that's a virtual drop in for an engine swap in Shoebox and similar cars, look for a commercially made header that fits the smallest car your engine came in. We're talking about stock cars from the factory.

In my case I had my GT 390 FE in a 59 Ranchero first time around and later it was in a 62 Ford wagon.
In both cases I bought headers for the 390 in a Mustang (a 1967 option).
In the Ranchero, only one pipe needed modification. (Front left one.)
On the wagon, two pipes were modifed. (The two front left ones.)

 

Headers at home

I did this tech on building mine a couple months ago.
Have a look and good luck.
TZ

 

Dan,
here is a set I bought for my RedRam all ready made. They are 1/4" mild steel, the fit is great and all for around $30. Here is the fella's e-mail, his name is Scott and I would recommend his product. I believe he makes them for other Hemi's as well as other motors. Contact him at:
nsmead@juno.com