Does it get any better than this Nth Degree suspension and tuck?

rjaym

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I'm looking at various tummy tuck /belly lift offers and it seems nothing compares to Mr Frends design (aka nth degree) - I am new to jeep ownership but am very familiar with NDM/AEV story and its history. Really what I'm asking here, does any vendor offer a design like this? look at this pic and then view what is common for long arm/midarm setups offered by the popular suppliers and its clear (to me) this set up has a measurable clearance advantage . It strikes me as odd why this design isn't the standard. Please educate me (and likely others) why the arm attaching points are not like this on "typical" kits being offered today. If another vendor has copied this design, or better yet, if anyone has a nth degree tummy tuck/lift etc for sale for LJ please let me know. My thinking is this design, coupled with todays choices in springs /shocks would make a fantastic on/off road rig.

nth degree tummy tuck.jpg
 
The problem lies in order to get the rear arms tucked the way they did requires the use of a "torque arm". And while it works well for on road handling the problem you run into especially with the six inch lift it has too much anti squat and would hop on steep climbs.
 
The problem lies in order to get the rear arms tucked the way they did requires the use of a "torque arm". And while it works well for on road handling the problem you run into especially with the six inch lift it has too much anti squat and would hop on steep climbs.

I had no idea there was a torque arm suspension for a Jeep. Learn something every day.
 
The problem lies in order to get the rear arms tucked the way they did requires the use of a "torque arm". And while it works well for on road handling the problem you run into especially with the six inch lift it has too much anti squat and would hop on steep climbs.
That and while the gyro joint was a neato exercise in how to try and do something different, it wore fairly fast when used with moderate enthusiasm. I'm not a fan of front radius arms wristed or otherwise. Far too many compromises were made to tuck the arms and at the end of the day, that isn't enough to make up for the rest. There was also very little thought given to weight. That skid is a beast in the weight department. The trans mount is also a lot more complex that it needs to be and for the folks where it rusts, an absolute nightmare to maintain.
 
Thanks for the knowledge base comments. I didn’t realize the skid was appreciably heavier. I’ll be making a effort to keep this build light as possible - every time I open the hood on this jeep I wonder if Chrysler made it out of lead - so heavy.
 
I'm not a fan of front radius arms wristed or otherwise.

Now that's something I haven't heard or read about since my Bronco days.

I know it's a lot to ask but I bet I wouldn't be the only one that would LOVE to see you summarize your experiences with various suspension link arrangements as compared to the 3 and 4-links we're used to seeing on coil sprung Wranglers. For example, I remember reading of axle tubes twisting in their housings on wristed radius arms, but it seems to be the whole point is reducing binding by eliminating the twisting load on the axle housing so the statics don't add up for me.
 
It's going to be very difficult to beat the simplicity of a Savvy short arm setup matched with a Savvy skid. This gives light weight, relatively easy installation, reasonable price, great functionality, reliability, along with 18" - 19" of clearance at the belly (With 33" or 35" tires). You'll have to modify the exhaust slightly, cycle the suspension for clearance issues, and set your pinion angle, but this will give you a rig that will perform beyond what most drivers will subject their Jeeps to.
 
Now that's something I haven't heard or read about since my Bronco days.

I know it's a lot to ask but I bet I wouldn't be the only one that would LOVE to see you summarize your experiences with various suspension link arrangements as compared to the 3 and 4-links we're used to seeing on coil sprung Wranglers. For example, I remember reading of axle tubes twisting in their housings on wristed radius arms, but it seems to be the whole point is reducing binding by eliminating the twisting load on the axle housing so the statics don't add up for me.

Radius arm setups bind horribly under articulation. Although Blaine could certainly explain it better, you can simulate how a radius arm works by doing the following: Stand with your elbows at your sides and bent at 90 degrees, hands pointing forward, thumbs up. Extend your thumb and index finger on each hand forward as if they were the upper and lower links on a radius arm. Your finger tips represent the control arm connection points to the front axle.

Keeping your elbows at your sides, move both arms up and down together and notice the relative positions of your fingertips. No problem there - meaning the axle moves freely. Now move your right arm up and your left arm down, and then vis versa, simulating articulation of the front axle. Pay attention to the relative position of your fingertips as you move your arms. Do this a few times and it quickly becomes clear that this motion induces a twist on the axle. Since the control arm mounts (and the axle, for that matter) are static, bind begins to happen almost immediately, and it quickly limits how far the axle will articulate.

I have personal experiece with this issue. The first suspension on my rig was a Rubicon Express with a radius arm in the front (I know, I know...). When I went to a 14" coilover my original plan was to continue with the radius arm (again I know, I know...). But when I mocked it up the suspension bound enough on articulation that it would not come close to using the entire 14" of travel. I then cut the entire suspension off and built a 3 link.
 
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Radius arm setups bind horribly under articulation. Although Blaine could certainly explain it better, you can simulate how a radius arm works by doing the following: Stand with you elbows at your sides and bent at 90 degrees, hands pointing forward, thumbs up. Extend your thumb and index finger on each hand forward as if they were the upper and lower links on a radius arm. Your finger tips represent the control arm connection points to the front axle.

Keeping your elbows at you sides, move both arms up and down together and notice the relative positions of your fingertips. No problem there - meaning the axle moves freely. Now move your right arm up and your left arm down, and then vis versa, simulating articulation of the front axle. Pay attention to the relative position of your fingertips as you move your arms. Do this a few times and it quickly becomes clear that this motion induces a twist on the axle. Since the control arm mounts (and the axle, for that matter) are static, bind begins to happen almost immediately, and it quickly limits how far the axle will articulate.

I have personal experiece with this issue. The first suspension on my rig was a Rubicon Express with a radius arm in the front (I know, I know...). When I went to a 14" coilover my original plan was to continue with the radius arm (again I know, I know...). But when I mocked it up the suspension bound enough on articulation that it would not come close to using the entire 14" of travel. I then cut the entire suspension off and went with a 3 link.

Yeah, I follow all that. I owned a series of TTB Broncos and Bronco II's and occasionally mused on an SA swap but always landed on that as an issue. But adding the wrist (on one side) seems like it would relieve it. Maybe in exchange for other issues. I never got anywhere near executing any of it.

1660142576312.png
 
Yeah, I follow all that. I owned a series of TTB Broncos and Bronco II's and occasionally mused on an SA swap but always landed on that as an issue. But adding the wrist (on one side) seems like it would relieve it. Maybe in exchange for other issues. I never got anywhere near executing any of it.

View attachment 349873

Interesting, I've not seen that setup before. Every radius arm setup I've seen for a jeep (kits, anyway) have been static. Has this been done for a Jeep?
 
Yeah, I follow all that. I owned a series of TTB Broncos and Bronco II's and occasionally mused on an SA swap but always landed on that as an issue. But adding the wrist (on one side) seems like it would relieve it. Maybe in exchange for other issues. I never got anywhere near executing any of it.

View attachment 349873
Lots of guys ran this and it works ok but adds an extra failure point and the axle was still prone to hopping.
Interesting, I've not seen that setup before. Every radius arm setup I've seen for a jeep (kits, anyway) have been static. Has this been done for a Jeep?
Metalcloak Lock and Load.
 
Interesting, I've not seen that setup before. Every radius arm setup I've seen for a jeep (kits, anyway) have been static. Has this been done for a Jeep?

The arm only looks static. It isn't. RE used a very simple method to relieve the bind in the form of Clevite style bushings at the axle and short upper arm connection to the main arm. What happens when you articulate it is the short upper pushes against the long lower and causes it to rotate around the long axis using the pliable connection in the bushings. The other way you can tell is RE did not include a reinforcement for the stamped sheet metal upper mount on the passenger side which are known to be less than robust and there are almost no reports of that mount being folded forward or dislocated. If the bind had not been alleviated, that would have happened with every kit. I say almost none due to never having seen one on the internet but don't discount someone may have incorrectly adjusted the arms and caused it that way.
 
The arm only looks static. It isn't. RE used a very simple method to relieve the bind in the form of Clevite style bushings at the axle and short upper arm connection to the main arm. What happens when you articulate it is the short upper pushes against the long lower and causes it to rotate around the long axis using the pliable connection in the bushings. The other way you can tell is RE did not include a reinforcement for the stamped sheet metal upper mount on the passenger side which are known to be less than robust and there are almost no reports of that mount being folded forward or dislocated. If the bind had not been alleviated, that would have happened with every kit. I say almost none due to never having seen one on the internet but don't discount someone may have incorrectly adjusted the arms and caused it that way.

Thanks for the clarity - that makes sense. For me, the RE setup seemed to work OK (in this regard, anyway) with 10" or 11" (for which I think that RE 5.5" kit was designed) or even the 12" shocks I ran at one time. But I think with the 14's it may have been pushing the flex limits of the bushings. Either way, I'm glad it's long gone from the rig.
 
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