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abadsvt
06-27-2008, 11:53 PM
Hi guys! I was thinking about building a custom set of headers for my project. I have always wanted to build a set and decided that i should just give it a try. Any tips or a how to would be much appreciated. Is there a specific sequence to weld the primaries to the collectors? I have always wondered how the weld in the middle as the fit the primaries into the collectors. Does that make sence? Also what is the difference between 304 stainless and 409? It is going to be for an LS1 basically stock with a few upgrades but nothing crazy. I was thinking 1 3/4" primaries and 2 1/2" exhaust. Does that sound good? Thanks ahead of time.

Josh

68protouring454
06-28-2008, 05:21 AM
once the headers are tacked, you leave collectors off and make a peice to weld in th emiddle of the 4 tubes, you also weld where each tube comes together, so once collector is on there will be no leaks
speedway motors has a 4-1 header kit for 169.99 its 18 ga but well worth the money, you may need a few 45's more however 45 are like 10 bucks each

B Schein
06-28-2008, 06:34 AM
I would check out Spd exhaust. I build custom headers in a professional shop we get all our header building material form spd they might be a little more expensive than others but they use high quality steel for all there bends and there bend are done on a very good machine which leaves the tube very round after bending which is a huge factor in fitting tubs together once they have been cut and realigned if the cross-sections are not round it will give even a experienced guy a hard time. Spd makes the little piece that you weld between that four tubes now they call it an (fc) star if you look in the formed collectors section of there catalog you will find it. We build our ls header 1 ¾ primary’s stepped to 1 7/8 with 3 inch collectors.

http://www.spdexhaust.com/

abadsvt
06-28-2008, 09:26 AM
Thanks for the replies guys!!! I went to SPD's website and didn't see that piece of metal that you weld on the inside of the tubes? Does anyone have a pic of what that metal looks like or a link to buy that piece? Also is it safe when i tig the headers up to just fuse them together instead of using welding rod as long as I cut the tubes tight toghether or do i need the rod for strength as the metal expands and contracts from the heat? I looked up to see what the factory LS1 has and they have 1 5/8" primaries and 2 1/2" collectors. Should i stay with factory sizes? I was hoping to run 2 1/2" exhaust. Thanks ahead of time!!

Josh

novanutcase
06-28-2008, 10:15 AM
Hey Brian!

Is this what you're talking about?

http://i56.photobucket.com/albums/g170/novanutcase/shoppics2-10-2007008.jpg

John

68protouring454
06-28-2008, 10:46 AM
no use some filler, but get .035 or .045 filler it keeps a strong weld, forgot the scientific explanation of it but you should use filler rod.
also that peice is easy to make, generally 3/4 x1/8 flat bar about a 5.8 piece, then weld the tubes together going towards the outside and inside of the header

ironworks
06-28-2008, 11:20 AM
I have built quite a few sets of headers and taught a handfull of guys in shop how to them. The absolute hardest part of building headers is the visual lay out of how the tubes will run. I'm a big fan of having as much of what goes under the hood in place, starter, upper control arms, etc. Then layout want tube will go in what position and how they will fit in the collector. The tack it all togther and try to get the best fit possible, it makes the welds look great. After you have 4 tubes cut them off one at a time from the flange and weld them solid. Replacing themback on the flange to the others to keep the collector location. Then once all 4 welded tubes are back in place, make the center transition for the middle of the four tubes and slide on the collector. If you buy the bad ass collector like John showed it comes with the middle in it, but they are pricey. But worth every penny.

If you get you part numbers togther I'm a dealer for SPD and I can save you alittle dough and drop ship them.

Good luck, Building headers are fun.

tjbruning
06-28-2008, 02:33 PM
Also check out Cone Engineering - www.coneeng.com

High quality collector kits that include conical collectors, merge bullets, assembly tools, transition cones, etc. Very competitive pricing as well.

http://www.coneeng.com/images/exhaustKits/kit1.jpg
http://www.coneeng.com/images/collector/pic2.jpg
http://www.coneeng.com/images/bullets.jpg

There header alingment tool will come in handy as well
http://www.coneeng.com/images/collector/pic8.jpg

abadsvt
06-28-2008, 03:00 PM
I have built quite a few sets of headers and taught a handfull of guys in shop how to them. The absolute hardest part of building headers is the visual lay out of how the tubes will run. I'm a big fan of having as much of what goes under the hood in place, starter, upper control arms, etc. Then layout want tube will go in what position and how they will fit in the collector. The tack it all togther and try to get the best fit possible, it makes the welds look great. After you have 4 tubes cut them off one at a time from the flange and weld them solid. Replacing themback on the flange to the others to keep the collector location. Then once all 4 welded tubes are back in place, make the center transition for the middle of the four tubes and slide on the collector. If you buy the bad ass collector like John showed it comes with the middle in it, but they are pricey. But worth every penny.

If you get you part numbers togther I'm a dealer for SPD and I can save you alittle dough and drop ship them.

Good luck, Building headers are fun.


I was hoping to buy a collector like that one. I am trying to get an idea on how i want to run everything so i can check on pricing to see what it will cost me to build them. If i go with this collector how do you weld in between the tubes? I photoshoped the above pic but you have to imagine it flipped over like if you were installing the tubes in the collector. I appologized if you alread explained that. It has been a long day:cheers:

Rodger I am a little confused about a few steps. Are you saying put the header flange on first then layout one of the tube to the collector and tack it to the collector. That way the collector is in a fixed position and then start with the other tubes? Did i get that or did I miss it by a long shot?

Thanks guys for your help. I really appreciate it. One more question. Do you think it will be a bad thing if i went with mild steel instead of stainless for the headers and exhaust? I have a feeling that everything might get really expensive. Will that affect the value of my truck?

Josh

ironworks
06-28-2008, 04:23 PM
There are 2 collectors from SPD one that is 4 individual tubes and one that has been formed on the outside to fit on to your 4 tubes instead of slide over the 4 tubes. The one that slides is either just partially welded or some guys build tabs to allow you to slide it off.
The 2 collectors are called merged collector and formed collector.

Asl far as doing one whole tube at a time it just depends on how difficult they are to snake through whatever you have to clear. I usually try to build the tube that can rally only go a certain path. The others are more flexible. Sometime you have to build or change tubes a few times to get everything to fit. This where you pick up time with experience and being able to use the scrap bends. You can tell a guy has experience building headers when he has one weld seam per bend and straight section. Not a weld seam on both ends of a straight section and multiple seams in one single sweep that does not change direction mid bend.

I would build your first few sets out of steel before, you step up to stainless. Stainless is pretty expensive. SPD makes really nice flanges that are CNC and not laser cut. They also use the absolute best materials so you welds look even better. 304 stainless is almost 3 times the price of mild steel and 321 stainless is about double the price of 308. .

chevyIIpost
06-28-2008, 08:50 PM
Do you guys back gas the inside of the tubes to purge the air when welding?

B Schein
06-28-2008, 09:47 PM
Do you guys back gas the inside of the tubes to purge the air when welding?


Its only necessary on stainless

parsonsj
06-28-2008, 10:13 PM
I wrote this a long time ago, but it may have a tip or two you might find useful:

Car Craft Header Story (http://www.carcraft.com/howto/0304_head/index.html)

jp

badmatt
06-30-2008, 11:00 PM
allways backpurge stainless. makes the joint 10x's stornger.

Perry Mitchell
07-01-2008, 07:01 PM
Here are a couple of tips I came up with that work really well for the novice. Use a slip collector, the kind that all your tubes slip into. Some are expensive, such as Burns and some are very reasonable, like Dynatech. Attach them where you want them to be when the headers are installed. I wanted my long tube headers to end near the transmission crossmember so I wired the collectors to it. Now go to Home Depot and buy some hub to hub stainless steel clamps, the kind that have 2 straps mounted to a corrigated center section. Throw away the rubber seal and cut 3 windows in the center piece at 12, 4, and 8 o,clock. Now start cutting your U and J bends and connect them together using the clamps. You can rotate the bends to get them aimed where you want them and when you have one tube connected from the flange to the collector, you can tack them together through the windows that you cut into the clamps. I prefer to not weld the collector to the tubes but rather bolt them together using tabs that are welded to the sides of the tubes.

tjbruning
07-08-2008, 10:13 AM
Josh,

The pictures are uploaded onto Cone's website (from the pdf file I sent you) if you want to check it out (better resolution, etc).

http://www.coneeng.com/weld_on_collector_kit.html

Also, check out Two Guys Garage this Saturday (9:30am EST) on the Speed Channel. They are building headers and a custom exhaust using components from Cone Engineering for a 61 Impala (built by Fuller Hot Rods) with an Art Morrison Chassis, 572 big block, etc.

XcYZ
07-08-2008, 11:02 AM
I'd love to see some pics of the headers that any of you guys have built. :thumbsup: