Custom Stretch 4 Link Double Triangulated on Dana 60's
04-10-2010, 02:15 PM
#11
Former Vendor
I can see why you might think that, but I'm afraid your solution would present quite the opposite result.
Running parallel lowers would decrease stability. Geometrically speaking, a triangle is the most structurally sound. Equilateral triangles (45 degrees at each angle) are the most structurally sound triangles.
This may be a bit wordy - but here's the logic: The angles of the arms at the lateral constraint points of the upper and lower bars (The imaginary point in space where the bars would meet if they were infinitely long) must combine to be at LEAST 45 degrees. Ninety degrees is the most structurally sound, but then one has to also factor in the affects on the roll axis.
Single Triangulated with parallel lowers may provide some clearance, but one would need a track bar to minimize bump steer. That, in turn adversely affects articulation.
Layman's terms: Double triangulated (theoretically) provides sufficient stability and butt loads of articulation. It just has to be dialed in right, hence this thread.
I'm going to tackle this project taking into consideration as much advice as everyone is willing to give me. I'm aware that the practical application of the setup will require many compromises, and I'm willing to make them.
I love the feedback though - I need all the constructive criticism I can get before I dive into this.
Running parallel lowers would decrease stability. Geometrically speaking, a triangle is the most structurally sound. Equilateral triangles (45 degrees at each angle) are the most structurally sound triangles.
This may be a bit wordy - but here's the logic: The angles of the arms at the lateral constraint points of the upper and lower bars (The imaginary point in space where the bars would meet if they were infinitely long) must combine to be at LEAST 45 degrees. Ninety degrees is the most structurally sound, but then one has to also factor in the affects on the roll axis.
Single Triangulated with parallel lowers may provide some clearance, but one would need a track bar to minimize bump steer. That, in turn adversely affects articulation.
Layman's terms: Double triangulated (theoretically) provides sufficient stability and butt loads of articulation. It just has to be dialed in right, hence this thread.
I'm going to tackle this project taking into consideration as much advice as everyone is willing to give me. I'm aware that the practical application of the setup will require many compromises, and I'm willing to make them.
I love the feedback though - I need all the constructive criticism I can get before I dive into this.
Also, take into account spring and shock loading/positioning when looking for proper instant centers because they will play a role in how much squat or anti-squat you feel in the seat of your pants!
Rock Krawler
04-10-2010, 03:15 PM
#12
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The double triangulation supplies the most amount of support for locating the axle side to side which supports your theory, but properly done single triangulation will work as well and not hurt the body roll as much as the double triangulated setup.
Also, take into account spring and shock loading/positioning when looking for proper instant centers because they will play a role in how much squat or anti-squat you feel in the seat of your pants!
Rock Krawler
Also, take into account spring and shock loading/positioning when looking for proper instant centers because they will play a role in how much squat or anti-squat you feel in the seat of your pants!
Rock Krawler
04-11-2010, 05:15 AM
#13
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Rock Krawler,
Actually, I'm hoping to take a page out of your book and use the stock JK Rear spring and shock setup that you were implementing with your X-Factor 5.5" Longarm Stretch. Will that be possible with my potential setup?
I really don't want to try for coilovers in all four corners. I think I will down the road, but I'm already stretching this project to the limit of my technical knowledge. Cutting through the frame and tub and integrating coilovers into a custom-fab roll cage is more than I'm willing to tackle with this phase of the build-up.
Actually, I'm hoping to take a page out of your book and use the stock JK Rear spring and shock setup that you were implementing with your X-Factor 5.5" Longarm Stretch. Will that be possible with my potential setup?
I really don't want to try for coilovers in all four corners. I think I will down the road, but I'm already stretching this project to the limit of my technical knowledge. Cutting through the frame and tub and integrating coilovers into a custom-fab roll cage is more than I'm willing to tackle with this phase of the build-up.
04-24-2010, 07:36 AM
#14
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Bend-Tech
Here's something I thought you might be interested in.
These are some initial mock-ups of how my cage could look. Now, since I'm currently in Iraq, I have no way to get accurate measurements, but I just played around with Bend-Tech, and am toying with some different styles.
This is what I came up with for the roll cage for "Silvo" (Still seeking a better name... I don't believe in simply choosing a name for a Jeep. It should be earned. So far, the only name given to my Jeep was "Silvo" by a friend.)
Again, this may seem like a lot of wishful thinking, but all of these mods WILL be done. I want to hit the ground running when I get back to the US (In August).
I'd love to get my hands on some measurements, if anyone has them from their builds. Also, if you have some Bend-Tech files of a working roll cage assembly, I'd love to look at them.
Angle View:
Side View:
Back View
Top View:
Feel free to offer constructive criticism. I love the feedback, good or bad.
- J. "Jon" Rogue
These are some initial mock-ups of how my cage could look. Now, since I'm currently in Iraq, I have no way to get accurate measurements, but I just played around with Bend-Tech, and am toying with some different styles.
This is what I came up with for the roll cage for "Silvo" (Still seeking a better name... I don't believe in simply choosing a name for a Jeep. It should be earned. So far, the only name given to my Jeep was "Silvo" by a friend.)
Again, this may seem like a lot of wishful thinking, but all of these mods WILL be done. I want to hit the ground running when I get back to the US (In August).
I'd love to get my hands on some measurements, if anyone has them from their builds. Also, if you have some Bend-Tech files of a working roll cage assembly, I'd love to look at them.
Angle View:
Side View:
Back View
Top View:
Feel free to offer constructive criticism. I love the feedback, good or bad.
- J. "Jon" Rogue
04-27-2010, 06:12 PM
#15
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its looking good, i'm wanting to do the same to mine this winter, i'm putting a 60 in the front, and i'm trying to figure out how to make a sterling 10.5 work in the rear 
i can't wait till august so you can get started and i can take some notes for this winter
thanks for the work your doing over seas
i can't wait till august so you can get started and i can take some notes for this winter
thanks for the work your doing over seas
05-04-2010, 07:27 AM
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Found some measurements for a TJ. I know it will be different than a JK, but I just wanted a good starting point.
Here is my new Roll cage design. I'll be using 1 3/4 DOM tubing with a 6" CLR, and 1" DOM tubing with a 3" CLR
As you can see, I added some risers for the seats, and bars to mount the harnesses. I also added a rear crossmember that follows the tailgate.
There is less negative space between the bars, so strength shouldn't be an issue. Hope you all like!
Here is my new Roll cage design. I'll be using 1 3/4 DOM tubing with a 6" CLR, and 1" DOM tubing with a 3" CLR
As you can see, I added some risers for the seats, and bars to mount the harnesses. I also added a rear crossmember that follows the tailgate.
There is less negative space between the bars, so strength shouldn't be an issue. Hope you all like!
05-06-2010, 09:04 AM
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inside of the frame rail is roughly 41 inches. i could be off a 16th or 2 since i was by myself.
and my frame rail is 20.5 off the ground, buuut i have a 5 inch lift and 37's. the next jk i see in a parking lot i'll hop out and measure for you.
bell housing bolt is 34''
i have no idea on the width of the axle, i looked online real quick but didnt find anything, i have a sterling 10.5 i can measure if you think they will be the same?
have you looked at the lenghs of your rear links yet? i'm playing with the 4 link calc right now i have my uppers 37" and my lowers 47" with that configuration i have 75% anti squat, i'm going to make multiple mounting points on the uppers so i can play the the antisquat b/c raising or lowering the uppers a inch, either raises or lowers the anti squat by 10%, and continues on that trend.
the only thing i haven't been able to dial in are my roll center (25") and my roll axis is (-4) but i have quite a few months to figure it up.
and my frame rail is 20.5 off the ground, buuut i have a 5 inch lift and 37's. the next jk i see in a parking lot i'll hop out and measure for you.
bell housing bolt is 34''
i have no idea on the width of the axle, i looked online real quick but didnt find anything, i have a sterling 10.5 i can measure if you think they will be the same?
have you looked at the lenghs of your rear links yet? i'm playing with the 4 link calc right now i have my uppers 37" and my lowers 47" with that configuration i have 75% anti squat, i'm going to make multiple mounting points on the uppers so i can play the the antisquat b/c raising or lowering the uppers a inch, either raises or lowers the anti squat by 10%, and continues on that trend.
the only thing i haven't been able to dial in are my roll center (25") and my roll axis is (-4) but i have quite a few months to figure it up.
