I need help making a set of tube headers

I have a special idea for my exhaust header system, and would like to make a prototype mock up that i can give to a tube bender shop to have the tubes bent the way i need them to complete my design, and to be sure they clear everything
any type of flexible tube that will retain its shape after being bent/ formed into shapes?
by hand would be awesome..
any of you header making dudes out there got any ideas for me?

I dont want to go buying a bunch of bends and such and hacking it all up..ive done that..this is a bit more involved than that

 

I've used the flexible rad hose or dont know if its available in the states in england i used a 1 1/2 flexible copper lines for mock up

 

that sounds possible..

 

Pvc znd a heat gun just a half lit idea.

 

Ive been bending electrical condiut(the grey plastic stuff) with a propane torch at work and forming it into different bends ..im using 3/4" conduit and and if you hold it in possition til it cools it stays where you want it.


this is a good possiblity, it might make a good enough model for a tube bender guy with CNC equipment to follow...or no?

 

Even a stiff piece of wire will hold its shape to set the design. Where is that draftsman when you need him?

 

Use the larger diameter pvc conduit--the heat gun and glue--should be near perfect..there are ( i hope in the states) springs for helping keep the conduits shape while you bend it
Now i think about it what about the flexible pvc conduit?

 

if you are going to have a tube bending shop bend it up just take some bends and tack them up they dont need to meet up flush. make sure you talk to the shop and check what ther min. grip is so they can try to bend them up in one peice. if they have a CNC bender they can just scan your tubes and bend then the same.

 

its too involved to do that..they will not get the bends right, and i dont have forever to cut and tack tiny pieces of tube 8 different ways to sunday for 8 exhaust runs.
the tolerance on these will not be shot gun..they have to be On! the money

I appreciate what you are saying..but the process would be way to labor intensive for what i have in mind to go at it that way.

I have done what your suggesting on less involved systems than this...i cant explain it

 

Check in at Woolf Aircraft in Romulus
734-721-5330
They can do it but it won't be cheap!

Dan

 

get flexable tubing bend it to shape and fill it with great stuff foam

 

thanks Dan.. i may try that..
I have a very good source, and friend to make them once i make him up prototypes
cost is a factor..i cant spend a **** load of money on this but a respectable exhaust system price is understandable, since i will be doing all the home work ..they will just have to plug it in and have at it.
I want to make it as easy for them as possible and do all the leg work for them

oh and anything with the words "Aircraft" in it..is expensive just to talk to them..I used to own an airplane..so that might be out of my budget just to ask questions

 

we can get the length, bend and rotation with in .003 we do highend exhaust all day long. flexable tube won't work because the radius will not be the same. if i can help in anyway let me know.

 

Ok..
I think i know where your coming from..
one of the guys I know of suggested bending steel tube..and he knows his **** when it comes to prototyping exhaust systems..its what he does ,, I was just bouncing it around here to see what others have done..

 

The flex steel tube that JC Whitney used to sell got stiff after it was heated, cheap too. Don't know if they still sell it or not.

 

it was flexible right out of the box?
sounds cool..designed for exhaust systems?

i should look into this..thanks

 

are you talking this stuff?

http://www.jcwhitney.com/autoparts/...01/Ntk-AllTextSearchGroup?Ntt=flex+steel+tube

 

Well, this is what I did, I got the header flanges, welded a flat plate over the port, then used Arc Welding rod. They come in 2/3/4' lengths and welded a piece to the flat plate over the port, then bent them where I wanted them, taking into account the pipe I was using was 1-3/4" OD. Took them to DCS in Sacramento (they build headers for NASCAR teams) and they did the CNC thing.........................and welded them for me. The guy doing the welding used TIG and you can hardly see the welds, they are that small.
They do look nice and fit like a glove.
As someone else said, It Aint Cheap to have it done this way, I think they spent about 4 hours taking measurements to put into the CNC program, but now I can have them reproduced for a fraction of the price I originally spent.

 

A chopped...they do look sweet..
sounds like the same type of idea that my guy was trying to explain to me how to go about giving him something to go on..
he told me to use steel line and run it down the centerline of where the tube is supposed to go..they will (CNC guy) will follow that centerline and map the bends and all using the tube i bend for the centerline as a "map" for the bends and any waves in the finished product.

 

Well, it was several years ago when I bought it, but the description at that time said, to effect, that it got rigid after it was heated. It did. The current description don't say that, so I'm not sure..................

 

i want these but dont have that kinda cash

http://www.icengineworks.com/icewmain.htm

 

One thing I should have mentioned, when your CNC guy makes the tubes, make sure either he or you TACK WELD them to the flanges you have......................because you want to be able to take the tack welds apart if they don't fit perfectly. I had them do this to mine and we found out that both front tubes needed to come in closer to the motor.
SO........................make sure everything is good before you start welding them tubes for the last time........................IMHO

 

This is very dangerous. People die every year from doing this and breathing vinyl chloride gas!!!!!!!!!

http://www.atsdr.cdc.gov/tfacts20.html

 

use this stuff and fill it with expanding foam

http://www.jcwhitney.com/autoparts/Search?catalogId=10101&storeId=10101&sku=faf5018

later jim

 

Maybe you could buy the stuff that was used in the mid 70's that went from the exhaust manifold to the air cleaner - on say a........77 olds cutl***. Carquest used to stock it. Just a thought. Todd

 

Wow. I just watched this video, linked from another car website:

http://www.stainlessheaders.com/customheaders

Even if you don't go with that company, you can still use the idea. Just use all PVC instead of their adjustable bends. Use 1 1/2" DWV pipe fittings from any Lowes or Home Depot. Grab a bunch of all the different angles and a 20' stick of pipe.

 

yeah i know what yer talik about..like 1.5" diameter silver clad heat riser tube

 

I know burning it is dangerous, and gives off a dangerous gas..
First of all im not catching it on fire..im just warming it up..second im not huffing the vapors off of it..and im not doing it in a closed in space..
Im well aware of the dangers this plastic presents..Ive been doing this at work for burner block port voids for many many years and have never had any issues..its all about doing it right and in the right conditions..its just like the myth busters say..we are professionals..dont try this at home..

we have the right equipment to keep the vapors vacuumed..and out of the work area.
vac hoods and resperators

 

absolutly..

thanks guys , some great information for all of us trying this on.
keep it coming, im all ears

 

use a piece of 5/16 steel fuel line to make a pattern of each tube, bend that tube and install it before makeing the next pattern , if you don't you WILL run into fit issues.... hey I only do it for a living.