Header Manufacturing: 3D Printed prototype blocks

I'm needing to fabricate my own headers for my Nissan VQ swap project and fell in love with the prototyping system by Ice Engine Works (https://www.icengineworks.com/) ... what a simple solution to an otherwise tricky problem. If you've not seen this system, check out the website and some videos ... its really cool for header design !!

What is not so cool for an end user making a one off is the price of all the required parts out of the US and the additional issue of bend radius's available in NZ versus the US being different.

I decided to get a 3D printer (now relatively affordable !!) and set about making my own similar system ... results so far are very good after some initial mucking about and prototyping. My shapes will match the actual bend radius's I will use and I will eventually make starter plates to bolt to the heads. Obviously there is the massive additional plus that I can prototype other parts needed before they get made, such as my transmission mounts that are also in the works.

I'm documenting the build over on the bimmersport forums so if you want to see how things progress when I've printed enough blocks to go 'full snake' on it you can head over there and keep an eye on things :) https://bimmersport.co.nz/topic/64728-blue-chunder-e46-318ci-vq37vhr-swap/

Pics attached to see where things are at.

well done it always fascinates me to see what others can do with the technology available

Regards Ross

Yes, there are a lot of things that 3D printing is a great tool for.

David, something you may not have considered is that rather than fabricating simple flanges to have the tubes welded to, you can model flange stubs that incorporate the first inch, or even quite a bit more, of the primary tubes to direct them where you need to run them - it can be much easier than welding bent tubes directly to the flange, and it can be used to form the transition from the port shape to the tube inner diameter.

Similarly, especially if using a turbo-charger, you can 3D print a prototype flange assembly which better directs the flow to the turbine inlet.

When you're happy with your design(s) you can have them 3D printed in SS, Inconel, or other metal of your choice using a commercial printer service, from your files. For example https://www.ram3d.co.nz/ - Not specifically recommending them, as I've no experience of them, just an example of the services available.

This is exactly what I am writing about, the printing rather than the scanning, you should find it of interest - https://www.youtube.com/watch?v=4jbn0ah3u9E

I imagine even local 3d printed metal stuff will be pretty expensive. Depending on the size of your 3d plastic printer, you may find it much easier to get in touch with someone that does sand casting to make parts of or all of your exhaust manifold without the cost of metalic 3d printing, you supply a hollow manifold in plastic, they fill in/around and fire tge casting sand them pour your manifold.

Good suggestion, Michael - some foundries can even use 3D files to print the cores and cast the part from there.

Not sure if it can be done, but a further option for some parts may be to 3D print them in wax and use the lost wax, or investment casting, method for making them.

i love the idea of an investment cast manifold from a 3D print, however i suspect you would need to work closely with a foundry.

reason being is shrinkage, when you cast a part it ends up smaller than the pattern. this also varies with material so a fixed rate cant be applied.

it wont matter so much on the flanges, the concern is wall thickness to me.

Josh, as you say, shrinkage can be a design concern, but it's a known value and can be designed in if required - it's usually around 2%, but rather depends on material being used, as you say - so may not actually be a significant concern.

Picked up a copy of Model Engineer this afternoon, co-incidentaly, because it has a short feature on converting basic 3D printers to make sand casting cores for casting model parts. Might be of interest to some - it's issue Volume 226, No 4662 9-22 April 2021. Some libraries may even have a copy, although you may need to inquire, or get it from another branch.