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Newest Project - Lower Intake Manifold for Fabricated S4 Intakes

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Old 04-15-2013, 12:42 PM
  #16  
hans14914
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I hope this helps clear up the CSA issue.

Attached are some renderings, both of the manifold with a plane drawn parallel to the tube mating flange (but pulled 10mm closer to the head flange) and several slices of the internal cross-sections.

I then used the plane to slice the model, and extract the internal cross-section of the port at that point. I then extracted the internal cross-section at the tubing interface and the exit port. There is a drawing of those in their actual location.

Finally, I oriented and aligned all the cross-sections so you can see how similar they are.

CSA from tube to exit is as follows:

Tube - 1569.577mm^2
Internal (10mm down from the tube mounting face) - 1550.789mm^2
Exit port - 1688.672mm^2

Now here is something you may find interesting. Drawing a plane parallel to the head seating flange, and moving it perpendicularly 10mm, using it to slice the model and extract an internal cross-section (so this would intersect the internal cross-section above, just at a different angle) is much larger, at a CSA of 1714.078mm^2. These measurements are not illustrated, but I can attach some later if necessary.

As the design of the insider of the port is complex and organic, it is not as simple as looking at CSA from one perspective.

Hope that helps,
Hans
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Old 04-15-2013, 12:48 PM
  #17  
blau928
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Originally Posted by hans14914
I have been toying around with this project for a while. For a long time I had my thoughts set a full cast part with an upper flange. It wasnt until this weekend that I went back to the drawing board. Spent all weekend testing various angles, and this is the "final" product. Dimensionally it is correct, but will add fillets, webs... etc as necessary as soon as I send models off to my machinist and foundry to see if it is more cost effective to machine or cast the part in the volume I think something like this will support.

First, to answer a question I know I will come up, the flange was taken from a S4 R2 head. I have no intention of doing a S3 or any earlier version. (the S3 and spider manifolds are slick anyway, why bother).

Second, it is designed around the later plastic body injectors. I have inserted the new EV14 injector model, and it fits, as well as Siemens Deka. I do not believe the original fat Bosch injectors will work, but I am making the overreaching assumption that anyone taking on a project like this would use a modern injector.

The upper "flange" is designed around a 2" OD 11g tube. This was selected for its nominal ID and structural support for some projects (like mounting ITB's or heavier plenums. There tube will sit inside the runner, providing a clean transition and collar for welding.

There is a clean and organic transition inside the part from the round tube bore, to the oval S4 port. Care was taken to try and match the entry angle into the S4 head. The injector pintle is shrouded, but can be opened up to expose it to the airflow with a mill. This was left closed to support the newer extended injectors.

You can see in the drawings attached that there is a 22.5degree bent tube in the assembly, but strait tubing could be used for a cross-runner system.

The injector boss is designed to limit the travel of the injector, so a rail without clips can be used. This boss will intentionally be cast tall for cutting down on a mill to support multiple injector dimensions.

I need to add some fuel rail hold-down provisions, which I will do today after considering the most modular approach, and hopefully will send this out tomorrow to find out if its better cast or machined, and then make the necessary final tweaks for the manufacturing method.

Please note, the linked PDF is a 3D file to be used in Acrobat Reader.

https://www.box.com/s/46gn29f56h5khafpm1ax

Thanks,
Hans
Hi Hans,

Very nice.. Congrats on making progress.. I can relate to the pain..

Cheers,
Old 04-15-2013, 12:48 PM
  #18  
ptuomov
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I am interested in the csa of the plane normal to the flow, which I believe corresponds to a very close approximation to the first set of numbers you gave, right?
Old 04-15-2013, 01:01 PM
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Lizard928
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Very nice Hans!

Wish these were ready and available when I was making my manifold....
Old 04-15-2013, 01:16 PM
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Tom in Austin
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Did it miss it somewhere? What is the rest of the manifold solution that goes with these pieces? Or is the idea that these are meant to connect to any sort of manifold design people want to develop?
Old 04-15-2013, 01:32 PM
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hans14914
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Tom,

I have a couple ideas I have been working on, but the idea was to create a part that would be usable across a wide range of applications. This could be easily used with ITB, short runners for a common plenum, front facing intake, or a long runner, dual plenum, twin-throttle setup like Phil Threshie's.

I am not ready to show my ideas for uppers, but wanted to let people know that these are coming soon if they have a project or idea that can use them.

Thanks
Hans
Old 04-15-2013, 02:18 PM
  #22  
BC
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Do you need any support from us in the process of finding someone that will make these at a reasonable cost?
Old 04-15-2013, 03:05 PM
  #23  
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No no no, just when I decided to stop thinking anything else but stock intake with some modifications

Doing something like this is clever as there is nothing like one_fits_for_all intake.

http://performancedesignllc.com/?page_id=247
Old 04-15-2013, 03:55 PM
  #24  
hans14914
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I have a couple foundries in mind. Pretty sure this part is going to end up being cast.

I have a quote to get a 3D printed test part for $240 which would be the next step to check all the clearances and fit before signing for investment tooling.

I am going to stare at it this week, double check everything, and then if nothing catastrophic happens in the next couple days, will put the order in for the 3d model out of Friday's paycheck.

Thanks
Hans
Old 04-15-2013, 03:58 PM
  #25  
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The 3D printing price is amazing. I really wanted to do one for myself and it was like 1200 dollars. Ridiculous.
Old 04-15-2013, 04:24 PM
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hans14914
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That price is for an SLA, so wont be usable structurally, but be very close dimensionally, which is what I am after for test fitting the injectors and testing the port matching and clearance with the waterbridge.... etc.

I will keep you guys posted.

Thanks
Hans
Old 04-15-2013, 05:42 PM
  #27  
GregBBRD
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I can guarantee you that if I could have had these made for $240 each, I'd have been all over it. I probably spent that much making the oval shaped pieces or getting them flat after the welding. Building pieces for these cars is a "love affair"...it makes no financial sense.

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Old 04-15-2013, 06:06 PM
  #28  
hans14914
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Greg,

That price was for 3D printing the test part, but honestly the cast part shouldn't be too far off that either. Sent out the file for review with two foundries I have decent relationships with, and should have an idea if there are any manufacturability issues, pattern and estimated production costs.

My goal is to keep them under $500/set. I will apply to be a Ross Machine Racing distributor closer to, and should be able to supply all the bits to make some interesting intakes. I think that it should be possibly to have sheetmetal intakes under the $1k mark, but don't hold me to it yet.

Thanks
Hans
Old 04-15-2013, 06:22 PM
  #29  
Tom in Austin
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Way cool Hans, keep up the good work!
Old 04-15-2013, 06:37 PM
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Hans--

Did you give thought to including bosses for throttle shafts in the castings? Drill and bush those with inner o-rings, and no need for separate ITB's. You already plan for injector bosses separate from the throttles, so maybe not a tough add-on?


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