DIY Headers

Great project, keep it moving forward.

 

These 4.0 engines are very good and are generations ahead. Once Ford gave these twin overhead cams in 2002, they became very powerful for their size. It is a pity that the world has shunned the humble 4 door RWD sedan as our Falcons with the latest generation 4.0 I6 along with our Holden Commodore 3.6 quad cam V6 would be the best value for dollar RWD cars in the world today. You have to start tipping in a lot more cash once you start looking at equivalent German or Japanese RWD saloons.

Also this header is set up for a right hand drive car, (something you do not have worry about!) as you can see where the steering column rack would pass just in front of the header where it would then connect to the rack. This whole header is designed to drop in behind the steering shaft and between the fire wall.

 

Yep! Moving forward is all I can do. I already gave HandyAndy my exhaust manifold from the Zephyr, and mine lost a chunk at one of the mounting bolts, so this header is IT!!!

Those 4.0 sixes can sure produce some mean power. Guys on the FordSix.com forums do all kinds of mods to max them out, and then find new ways to milk them for more!

 

For unknown reasons, our big box building supply stores don't all carry 1.25" I.D. PVC pipe or fittings. I'm using that pipe to do the modelling.

Out of curiosity, I checked the store's website that sold me the pipe (RONA Building Supplies), and found they had fittings that could save me some time, and help me nail down the angles.

They also has some short 45 degree joints that fit inside the pipe. I bought 2 - 90 degree and 12 2" long 1.25 O.D. (1" I.D.) nipples to join the pipe sections, where I can't fit them with any tight angles that may develop as I move ahead.



There's a few companies that make commercial header modelling kits using PVC components (not plumbing pieces, for sure), that they can make a racer's headers from, so this should keep the project on track.

No. 1 exhaust Port, will be the toughest, but I think the AC bracket compressor mounting holes have some room to be moved up to 3/8" away. That should do it to soften the angle going into the flange. We'll see...

 

Hey Norman it looks like you are now serious and finally ready to give it a go! If I may, I can give you a few basic start up tips and suggestions that may be able to help you to decide the best angle of attack from the beginning, hopefully saving you from wasting time and money along the way.

If you are planning to make a prototype pipe by using wire or poly pipe so that it can be taken to an expert to be replicated in to a one piece pipe design (avoiding the need to cut or shut), then you will need to consider some of these following points.

Be careful about wire templates as you will need to replicate the centre line radius exactly to what the tooling will bend. If you don't pay attention to this part, you will not be able to control where the pipe will end up because while the wire will fit, the full sized pipe with its "set in stone" centre line radius will not match the wires position and the pipe even with the right degrees in the bend, will end up nowhere near where your wire was bent and placed as the sample. Personally, I think this is a very hard way of doing things but you may find an easy way around to making this work. But either way, make sure understand what the centre line radius is on the tooling from the bender you are working from. Ask if there is several tool sets in your size with different centre line radius’s that you can choose from.

During the wire sample stage, be aware of a false radius inside of the bend radius. Have a look at the picture of the header on the Aussie six header design. See how No1 pipe actually screws thorough the entire bend radius that suits the design of this header as you can see that it needs to keep screwing around to meet the intended junction at the first collector. Looking at this pipe, I can see several induced radius’s along the line of the bend. This type of pipe design cannot be replicated straight off of a regular tube bender as you will need to have a more specific push roller type machine that they use to bend parts like hand rails etc. I also think you will find that this particular header was hand built from sections so this type of "crabbing" (certainly won’t hurt the header of course!) was built into it as they went. But if you try and bend a wire template this way and then take it to a tube bender operator, there is no way a regular tube bending machine with its set in stone radius will be able to replicate it and the pipe will simple end up somewhere else once it is bent.

The next one is far simpler to get your head around. There is no way you can produce a pipe with bend on bend characteristics without specially made tooling. These tooling parts are specially designed to make millions of parts so they are economically viable build, but you certainly will not have this option if you want have you tube bent from one length. Ok to explain what this all means for you is, you will need a specific required minimum distance between the bends for the gripper blocks to hold on to when bending the next bend in the sequence. All mandrel benders require this minimum distance on standard tooling and even most press benders need it also. Some press bending machines because of the way they work, can have some of the tooling removed to clear a path for the pipe to sit for the next bend, but most benders do not work this way. For 38 mm we work on around 60 mm of minimum distance between bends, but be careful as most tube bender companies work on a minimum of 2.5 which means for 38 mm it would work out to 95 mm or nearly 4 inches between bends. Talk to your tube bender people to show you what you can and can’t do.

The last main considerations you will need to allow for if you are intending to use a commercial tube bending machine is, some tube benders (in fact most) need a program to run. This may not be an option for you as even this process will waste some parts during the programing stage, but it is also pretty time consuming anyway which will cost money. The other method of bending using these machines is to use a mechanically set up tube bender (one that dose not need a computer to drive it). This type of machine is normally reserved for smaller tubing such as 1 ½” or 38 mm and is fairly common. They do not require a program because in most case the operator can work of line of sight manually calculating the rotations and distance between bends etc., from the sample.

Your idea about building the header around a template outside of the engine bay is a good idea as there is so much more you can do. The only thing you will need to do is to still keep periodically back checking your header for the necessary clearances and even pipe angles and pipe direction inside of the engine bay because no matter how good your template is, you will not capture the true essence of how the header is beginning to form outside of the engine bay and remember, it always looks better on the bench than it does inside the engine bay!

Have a read through what I have written up and let me know if you have any questions. Also once you have figured out the way forward from the original design concept, don’t start welding everything together until you have checked back with me. I may be able to help you keep any mistakes down to minimum (seeing as I have made most of them myself already!)

Cheers Mike.

 

I used the wires to see how they would meander amongst themselves, and along the length of the motor. I'll be starting the PVC model today. I'd like to keep the heat away from all the hoses (AC, Heater, Vacuum, and the eventual 3 carburetors), so weaving the header tubes from the block to let me add mounting tabs for the aluminum heat shield (using a common aluminum stair tread), that will be welded onto at least 2 pipes, with the shield bolted at 3 of the header flange bolts. (You likely know how these 3.3L sixes always boiled the fuel in the float bowl.)

All that contortion in that Aussie header picture doesn't seem necessary for my engine. I hope to keep the segments (crabbing) to a minimum, but if the bender can with their technology, I'll certainly pick their knowledge for the best compatible way.

Once I assemble the mockup into the car bay, I'll assemble the PVC bits with machine screws and sheet metal screws to take it to the bender and welder. Hopefully, the ceramic coating shop won't distort it in their processes.

The "bend on bend" issue is where I expect 'segments'. I don't think any of the bends will be sharper than 22.5 degrees (half of 45 degs.) and if they have to change direction in the same tube, well so be it.

The bender does do handrails and I've seen his bends on stainless 2" tube, where I bought the tubing. They also had a display of some of his LAB-grade tube bending capability and small aircraft headers. He's the only one in the middle of Canada - no one for 800 miles on either side of us.

Our currency is in the crapper, and the one company that produces SS bent header components is on the US side. So the local guy is gonna get the work.

http://www.stainlessheaders.com/index.aspx

I saw some old pictures of hotrodders from the post-war days making their own pipes from steel conduit, with welded up bends (corners), at 45 and 60 degree angles. and if my No. 1 exhaust port has to be done that way, I'll do it. But as you said, a good bender might get around it.

So far, all the parts I've restored or made up, look like gem-quality on the bench! But the header intimidates me, so once it gets warmer in the next 10 days, I'll be installing the motor and finalizing the fitment on the car.

Wow! Not just for this info, but because I actually got it!

QUESTIONS:

Yeah, tucking the two tri-y collectors into the 2-in-1, or should I have a short tail on each to fit into the 2-1? What I see is to remove a small segment in each and Siamese the 2 TRI-Y collectors into the 2-in-1, as an option.

Oh yeah! I'll be posting each of my baby steps as I get them worked out, and especially before final welding.

Awesome assistance, Mike. Truly appreciated.

 

Hi Norman, great stuff! Ok for the outlet, what you are looking for is what we call a Y-piece. Have look at the header I posted a couple of pages ago

This is exactly how we finish our old school Falcon headers even now, mainly because back in the day (the mid 70's and early 80's!), it was almost a ritual for a young buck (me included!) to run a twin 2" system even on our Aussie sixes, but we also now know better today as a single 2 1/2" system for a six is a far better performing system overall. Ok I don't think I supplied a two way collector cone with the kit I sent to you, but you should still set your header up like this anyway. Ask your local exhaust shop, or search on line for this part

Which I found here (Aussie ebay) under Y piece exhaust
http://www.ebay.com.au/itm/Jetex-Un...710?pt=LH_DefaultDomain_3&hash=item45fd9827b6

Although it is a universal part, this would even come close to fitting our headers as well!

The other thing to consider is, if you get this part first then you can wire it into place right where you want you header to finish and then aim for this point when you start to build your header. For me, no matter if it is a y-piece or a flange connection or even a cat convertor, this is exactly the same method I use to steer my headers into the right position under the floor.

 

Actually, you did include a 2-in-1 Y-pipe collector. Different from that universal type. It's further up where I show my Wire Map pics. Post 104 on page 11.

 

More progress on the Header modelling. I went and got more of those 45 degree joints, but only to fit inside the PVC tubes, not outside. Whatever I don't use, I can return.

Since the exhaust ports are square, and the end elbows are round, I set up my table saw with a 60 tooth blade and squared them off to fit. If they were a bit sloppy, I stuck some electrical tape to tighten them up.

I had some cardboard mailing tubes (1-3/8" and 1.5") and cut them to fit in the other exhaust ports to get a sightline to the collectors.

Now maybe its my linear brain, but I like this looks a lot better than the wet noodle pipes:









The PVC tube cuts nice and clean on the table saw, and I do have a metal cutting blade for it too, but I'll likely tune up my bandsaw to cut the stainless tube, and my Makita belt grinder, in a jig I made to use it as a beltsander to cleanup any rough cuts or set the angles more precisely.

Unless there's some mysterious reason why not, as I've got this laid out, the end pipes will pass behind the others, closer to the block, but still 5" away as they travel downward. The rear pipes have to travel forward anyway to clear the starter length (so I can repair or replace it), and that will allow a good size curve, back into the top TRI-Y collector.

Any comments are welcome...

 

Ok cool, I thought I would have included that in the kit, whether it is a Y-piece or a 2 into one collector, it is one less part you need to find. I'm am a little confused by your question about the 2 into 1 collector though. Are you asking how long the secondary pipes are meant to be? Or where the 2 1nto 1 collector should be?

 

Sorry this is where the confusion is. Actually reading it again, you are asking about the secondaries I think.

There are a few different types of headers for a 6 cylinder dengine, but the two most common old school designs are the semi tuned header that features short primary pipes with long secondaries, and the tuned header which is basically the opposite with very long primaries and only short secondaries like the one I have featured on this thread already. If you look at this header again then think of it like this, if you choose a twin system with this header then in theory you are either running two very long secondaries that travel over the diff and end up as tail pipes, or none at all as this is actually the exhaust system!, however if you use a Y-piece to a single exhaust with this design then you can see that you are only using very short secondaries to complement the very long primaries with this tuned design.

Ok the difference between these two designs is, the semi tuned headers are designed to promote good strong midrange torque on standard or near standard engines, while the tuned design headers are designed for top end hp by shifting more air at high rpm through multi barrels or carbies and high lift cams etc.

For you I recommend the semi tuned design and looking at your progress so far, that seems to be exactly what you are designing, but you will need to factor in secondaries to make it worth your while or you will only be making something that would perform marginally better than a standard manifold. You can make a shorty header but to get any real benefit, you will need to use much larger (in diameter) primary pipes though.

 

Ok don't get too involved with the whole header at this stage. However its still fine to leave all of the pipes where they are for the moment but you will need to concentrate on the first two pipes for now.

If you are happy with the position of No 1, then align No2 so that it runs down the face of the block and above No1 best you can. This will allow No 3 to move forward and then sweep back into the valley formed by the junction of the first two pipes. The lengths can then be determined once they have come together. You will need to form this junction (as close to the face of the block as possible) before you can move onto the rear half of the header.

Cheers Mike.

 

It appears that I have to nip out about a 1" wide X 1.25" arch on both the tri-y collectors to mate them into the 2 in 1 final collector, OR I could simply weld tails on the try-y collectors and feed them into the 2-in 1 final collector? I'd rather not nip out the collectors.

I've read both your comments, but given a 12" tail extension on each of the TRI-Y collectors, I'd gain some length on the primaries, before they merge.

 

Yep! The No 1 pipe and No 6 pipe will get the same bend coming out of their flange, with No 2 close to the block, and No 5 almost on the same plane from the block as No 2. No 3 and No 4 will protrude further toward the fender well.

I have more protractors than I care to count, some I've made for special wood projects. So I was working a simple one that I can swivel up to three angular sections between the non-curving sections.

I'll finish it up tomorrow and post a pic. Once I get it refined, I'll draw it up and post it into a *.PDF or *.DWG 2-D drawing.

 

I do a lot of widgets and jigs for my various hobbies and tasks on the house, our custom-built furniture and special kitchen hardware and gadgets, as well as my shop and car. That makes me a qualified packrat.

Anyway, I didn't want to experiment with my 1.5" stainless tubes, and looked up in between the basement joists, for some metal tubing and I found a floor lamp post tube exactly the same as the stainless tube. AND I found another cardboard mail tube that slipped over it like a snug glove. I know the No 1 and No 6 ports are the challengers in this project. No 1 because I don't want to move the stock AC, and No 6 because it has to leave enough space from the above the starter, and curve back into the collectors.

So the question I was tinkering with is how can I make a segmented 90 degree port exit?

Then I found a couple youtube flics to mark and fabricate tubing and light gauge channel, even a couple on making tube bender components from wooden parts. Also found one on a product made from magnetic plastic sheet called Wrap-It. Only that won't stick to non-magnetic stainless. So I cranked up my table saw, after making sure it was square to the blade and the mitre gauge was accurate, to cut the cardboard mail tube at different angles. Then I marked off a section of the lamp tube to cut on my band saw tomorrow.

Nice straight-on view of a 200 Cylinder head!


My humble bandsaw (It was made by Ryobi for Craftsman) needs a few tweaks after I change the blade.


Also found a nice clear picture of 200 I6 with the same AC unit, and estimated the space at 7/8" between the intake manifold and the AC compressor. I got it from an Image Search via BING.COM.


That allowed me to clamp a chunk of 3/4" wood and see if my plastic piece could come out from the bloc a bit more and still leave room to let incoming fresh air run in between to keep the AC in good shape:


This is the marked up lamp tube, and my assortment of tube marking 'tubelates'. I did one for 30, 45, 22.5, 11.25, and 5.625 degrees.


Once I test this tomorrow, for bending angles, I'll tack it together, and form it into the flange to see how much it distorts (round plug into square hole).

Here's the youtube links I'm using to guide this experiment:

Tube Bender With Hardwood Wooden - Wood Die
https://www.youtube.com/watch?v=bktdn-ZFIvg

How to fabricate a swept 90 degree bend in cable tray - YouTube
https://www.youtube.com/watch?v=CEy-Wue-gPc

Wrap-It-Cut Magnetic Welding Templates
https://www.youtube.com/watch?v=uQ5efBsjY5Q

How to Seamlessly Join Two Pieces of Pipe
https://www.youtube.com/watch?v=sTdVq8x0l58

I used the 11.25 degree template to draw on the steel tube. I had to reverse it to mark the opposite cut. So each notch is a 22.5 degree cutout, making 4 gradual bends to add up to 90 degrees. I may have to do it over with the 5.625 template to make the notches only 11.25 degrees, if it doesn't make for a smooth enough curve.

I'm an engineer, so Form, Fit and Function are more critical than curvaceous grace.