How to cut this merge collector?

[2uzgte]

I'm having trouble cutting this merge collector, maybe someone can help.

I have very tight spacial constraints and because of other factors with the turbo setup, I have to stick to them with this project. I have 1.75" primaries and the center tube in the picture (number 2) is limited to 3" long. I need to merge cylinders 1 and 3 into tube 2 in a splayed fashion, and I'd like to do so at around a 45 degree angle. I tried a few geometry calculations, but I'm doing something wrong. I spent a day making a jig for my bandsaw that keeps the piping true the entire way through the cut (sans the blade deflection) so if I can get the measurements/angles down correctly, I can get this cut and tacked.

Based on the pictures, can anyone give me some angles? I know it has to total 360 degrees and the manifold flange outlet is circular, are my angles wrong?

I'm not sure how to calculate the width of the remaining front fascia of the pipe, based on the angles either? Does anyone have a formula for this?

Thanks for reading.


http://img829.imageshack.us/img829/7...collector1.jpg

[2uzgte]

1.75" in diameter, 5.5" in circumference


0.4583333333333333" (arc circumference of 30 degrees)
0.9166666666666667" (arc circumference of 60 degrees)
1.833333333333333" (arcbcircumference of 120 degrees)


Tube 1 - 1.8334 in circumference arc length from 30 degrees to 150 degrees
Tube 2a - 0.9167 in circumference arc length from 150 degrees to 210 degrees
Tube 2b - 0.9167 in circumference arc length from 330 degrees to 30 degrees
Tube 3 - 1.8334 in circumference arc length from 210 degrees to 330 degrees


I believe, after thinking about some geometry, that this is what the measurements would be?

I had some help from this page

http://www.handymath.com/cgi-bin/arc18.cgi?submit=Entry

http://img10.imageshack.us/img10/251...collector2.jpg (how do I display an image here?)

[2uzgte]

I guess you can't display pics, you attach them, so here they are to keep the thread neater

[joebie]

https://fbcdn-sphotos-a.akamaihd.net...96775557_n.jpg

I just did this 2-1 for an uppipe to a t3 flange for a turbo.

I used the chop saw.

Check this link out also for some other tips - This guy does a pretty decent job.
http://honda-tech.com/showthread.php?t=2787713

Originally Posted by 2uzgte

I'm having trouble cutting this merge collector, maybe someone can help.

I have very tight spacial constraints and because of other factors with the turbo setup, I have to stick to them with this project. I have 1.75" primaries and the center tube in the picture (number 2) is limited to 3" long. I need to merge cylinders 1 and 3 into tube 2 in a splayed fashion, and I'd like to do so at around a 45 degree angle. I tried a few geometry calculations, but I'm doing something wrong. I spent a day making a jig for my bandsaw that keeps the piping true the entire way through the cut (sans the blade deflection) so if I can get the measurements/angles down correctly, I can get this cut and tacked.

Based on the pictures, can anyone give me some angles? I know it has to total 360 degrees and the manifold flange outlet is circular, are my angles wrong?

I'm not sure how to calculate the width of the remaining front fascia of the pipe, based on the angles either? Does anyone have a formula for this?

Thanks for reading.


http://img829.imageshack.us/img829/7...collector1.jpg

[2uzgte]

Hey Joe,

Thanks for the reply, I found that thread via google and used his protractor setup

The 2-1 I have done without too much issue, I'm hoping someone can confirm or deny my angles for the 3-1, as that has me just wasting pipe.

Can a 3-1 not be done with 3 straight pipes, do I have to use bends? I've seen people use drill presses and hole saws, should I be doing that instead?

Originally Posted by joebie

https://fbcdn-sphotos-a.akamaihd.net...96775557_n.jpg

I just did this 2-1 for an uppipe to a t3 flange for a turbo.

I used the chop saw.

Check this link out also for some other tips - This guy does a pretty decent job.
http://honda-tech.com/showthread.php?t=2787713