Long Arm Lifts vs. Short Arm Lifts

However...I do plan on buying control arms that will allow me to add longer links in the future, if I'm so inclinded.

It would be rare for that to work. We generally tell folks with the Currie Short Arm that do the mid arm to just take the set and sell them intact. The only joints that work are the lowers moved up to be the ends of the 3 uppers and then you are left with 1 lower and 4 uppers to do something with IF you are working with something like the Currie or Savvy arms.

If you move to a "3 link" front with a single upper, I recommend the larger body for more durability but with the smaller 1" shank. You don't need the bending resistance of the larger shank so the smaller one works fine.
 
It would be rare for that to work. We generally tell folks with the Currie Short Arm that do the mid arm to just take the set and sell them intact. The only joints that work are the lowers moved up to be the ends of the 3 uppers and then you are left with 1 lower and 4 uppers to do something with IF you are working with something like the Currie or Savvy arms.

If you move to a "3 link" front with a single upper, I recommend the larger body for more durability but with the smaller 1" shank. You don't need the bending resistance of the larger shank so the smaller one works fine.
Interesting. I was thinking that a CA like Savvy, that is threaded on both ends, would work fine. You're saying that with longer links, you need heavier joint ends though...right?
 
Interesting. I was thinking that a CA like Savvy, that is threaded on both ends, would work fine. You're saying that with longer links, you need heavier joint ends though...right?

I can tell you from having both the Savvy short arms and now the Savvy mid-arms, the diameter of the tubing on the mid-arms is substantially larger (it's very noticeable), and the JJs themselves appear to be much bigger as well.

If the short arms weren't at the powder coater right now being done, I would take a picture of one side-by-side with my mid-arm.
 
Interesting. I was thinking that a CA like Savvy, that is threaded on both ends, would work fine. You're saying that with longer links, you need heavier joint ends though...right?
As the link length increases, the leverage potential moves up much higher. Higher leverage potential means the lever has to be stronger. What folks miss is how that can happen and the forces involved. If you are climbing even a small waterfall or even a rock obstacle and there is a lot of weight on one of the front tires lifting the rig, if that tire slides off to the side and there happens to be a perfectly located rock right in front of the lower control arm mount that acts as a fulcrum, you can wind up with a spring load of 2000 pounds or so pushing down on the axle and a fulcrum only a couple of inches away from the control arm bolt. Essentially you are trying to lever the chassis up with a high force and a short fulcrum distance to the load. That will bend a 1" shank easily or the arm, or both.

We have seen many bent RE long arms doing just that.
 
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As the link length increases, the leverage potential moves up much higher. Higher leverage potential means the lever has to be stronger. What folks miss is how that can happen and the forces involved. If you are climbing even a small waterfall or even a rock obstacle and there is a lot of weight on one of the front tires lifting the rig, if that tire slides off to the side and there happens to be a perfectly located rock right in front of the lower control arm mount that acts as a fulcrum, you can wind up with a spring load of 2000 pounds or so pushing down on the axle and a fulcrum only a couple of inches away from the control arm bolt. Essentially you are trying to lever the chassis up with a high force and a short fulcrum distance to the load. That will bend a 1" shank easily or the arm, or both.

We have seen many bent RE long arms doing just that.


Makes sense...especially the strength of the link arm needing to be greater. And, I suppose with more leverage potential, you need larger/ stronger mount brackets and larger mounting bolts to resist that extra force...ergo, larger joints. Something else to think about. Just when I think I've figured out what to buy... someone comes along and gives me a little bit more information that makes me change my mind again.
 
Makes sense...especially the strength of the link arm needing to be greater. And, I suppose with more leverage potential, you need larger/ stronger mount brackets and larger mounting bolts to resist that extra force...ergo, larger joints. Something else to think about. Just when I think I've figured out what to buy... someone comes along and gives me a little bit more information that makes me change my mind again.
The hardest part of all this is knowing if what we don't know matters. We had a friend many years ago ask who would build him a rear Dana 44 that retained the ABS tone rings on the axle shafts. After much research, he found that Dynatrac would do it and he paid a bunch of money over what he could have gotten the same thing for from Currie and others or even a stock one for that matter except back then, a Dana 44 was not ABS compatible.

Fast forward a few months and a few more trails in JV, he finds the need to install a front hub conversion which totally negated the use of ABS. He paid nearly double for something he now could not use.

The better question would have been, do I need ABS?
 
The hardest part of all this is knowing if what we don't know matters. We had a friend many years ago ask who would build him a rear Dana 44 that retained the ABS tone rings on the axle shafts. After much research, he found that Dynatrac would do it and he paid a bunch of money over what he could have gotten the same thing for from Currie and others or even a stock one for that matter except back then, a Dana 44 was not ABS compatible.

Fast forward a few months and a few more trails in JV, he finds the need to install a front hub conversion which totally negated the use of ABS. He paid nearly double for something he now could not use.

The better question would have been, do I need ABS?
And, we're right back to where we started..."What do you want to do with your rig?" :)
 
A Slight derail, but those pictures that @Blackjack posted really have me thinking...I've been playing with the 4-link calculator from Pirate, and came to the same conclusion last night...I have a body lift so I have the room to raise my upper link mounts. That would get the arms back to "normal" flat conditions... Its interesting. I will need to spend some time with a tape measure under the jeep and with my nose buried in a book to really learn what anti-squat and roll center means...or more importantly, what effect they have on the jeep.

The track bar bracket I have is taller and IIRC called for 3 inches total bumpstop with no body lift. Something to note playing with the calculator, if you run a track bar it is your roll center control and not your control arms.
 
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A comment about the Nth axle side mounting. Broadly speaking, when the lowers are raised, the leverage against the mounts is decreased. When the uppers are raised, the leverage against the mounts is increased and ought to be strengthened. It isn't uncommon to see these raised mounts bend if the bracing is insufficient. Raising the uppers eventually also reduces the up travel to where the mounts will eventually hit the floor of the tub.

This is one of the problems you'll see when guys try to add ground clearance by moving the lower axle mounts higher.

You are correct but they also increased the vertical seperation and that helps with some of that. This was where a lot of guys ran into problems on Pirate, they broke a couple rules. First and most importantly was you need to keep your lower link mount below axle centerline or link loading gets real funky. Second and as Blaine has noted vertical seperation of the links is crucial. All too often that calculator can work to ones detriment as packaging always comes first and optimization second.
 
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For the suspension gurus on the forum, does the teraflex LCG pro system look like it has a good design / reasonable geometry?

https://teraflex.com/shop_items/tj-...lexarm-lift-kit?vehicle=LJ Wrangler Unlimited

I bought into the hype that longarms were the way to go for the best combination of articulation and on road handling (long before I found this forum) so ended up with the LCG enduro kit (only replaces the lower arms). I now have the problem of long lower arms and short upper arms that results in a lot of rear end hop when climbing really steep rock inclines. I’m wondering if going to the new uppers as well will improve the geometry (plus I’m hoping for improved performance on rocks with the triangulated rear).

As an alternative, I’ll go to the savvy midarm setup, but since I already have the teraflex lowers, I can do the teraflex pro far cheaper (probably save $2500). If it looks like the teraflex kit is fundamentally flawed, it’s worth spending the money, but if the teraflex kit looks pretty good, I’d like to save the cash.
 
For the suspension gurus on the forum, does the teraflex LCG pro system look like it has a good design / reasonable geometry?

https://teraflex.com/shop_items/tj-...lexarm-lift-kit?vehicle=LJ Wrangler Unlimited

I bought into the hype that longarms were the way to go for the best combination of articulation and on road handling (long before I found this forum) so ended up with the LCG enduro kit (only replaces the lower arms). I now have the problem of long lower arms and short upper arms that results in a lot of rear end hop when climbing really steep rock inclines. I’m wondering if going to the new uppers as well will improve the geometry (plus I’m hoping for improved performance on rocks with the triangulated rear).

As an alternative, I’ll go to the savvy midarm setup, but since I already have the teraflex lowers, I can do the teraflex pro far cheaper (probably save $2500). If it looks like the teraflex kit is fundamentally flawed, it’s worth spending the money, but if the teraflex kit looks pretty good, I’d like to save the cash.

Sorry - linked to the LJ kit instead of TJ. Here’s the correct link for the teraflex pro.

https://teraflex.com/shop_items/tj-...rm-lift-kit-w-9550-shocks?vehicle=TJ Wrangler
 
For the suspension gurus on the forum, does the teraflex LCG pro system look like it has a good design / reasonable geometry?

https://teraflex.com/shop_items/tj-4-0-unlimited-pro-lcg-long-flexarm-lift-kit?vehicle=LJ Wrangler Unlimited

I bought into the hype that longarms were the way to go for the best combination of articulation and on road handling (long before I found this forum) so ended up with the LCG enduro kit (only replaces the lower arms). I now have the problem of long lower arms and short upper arms that results in a lot of rear end hop when climbing really steep rock inclines. I’m wondering if going to the new uppers as well will improve the geometry (plus I’m hoping for improved performance on rocks with the triangulated rear).

As an alternative, I’ll go to the savvy midarm setup, but since I already have the teraflex lowers, I can do the teraflex pro far cheaper (probably save $2500). If it looks like the teraflex kit is fundamentally flawed, it’s worth spending the money, but if the teraflex kit looks pretty good, I’d like to save the cash.

I am surprised that Tera still sells that kit. There are so many problems that manifest themselves with that amount of difference in link length that I am sure you are experiencing. They would have been better off with making the front a radius arm like RE does than to keep the short upper. The rear is whole other story with horrific pinion angle changes just to start.

The biggest problem with their upgrade is their arms are still too long and thus the vertical serpation at the frame is less than ideal. While triangulating the rear does decrease bind in the suspension I still like a track bar for controlling roll center. Unless you have made major changes to increase shock travel you will run out of shock travel well before track bar bind becomes an issue.
 
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I remember watching an LJ with the Teraflex long arm continually go into weird oscilating wobbles whenever something halfway interesting showed up.
 
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I still like a track bar for controlling roll center.

You're not the first person to say this. When talking to Dave Kishpaugh about whether he thought the Savvy mid-arm or his custom made "Jeep West" mid-arm would be better for me, he was really, really trying to sell me on his setup due to the fact that it uses a rear track bar, and thus has much better "roll center" than the Savvy mid-arm.

Ultimately I had issues with Dave and the way he runs his business, so I ended up going with the Savvy mid-arm, and I'm really happy I did.
 
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You're not the first person to say this. When talking to Dave Kishpaugh about whether he thought the Savvy mid-arm or his custom made "Jeep West" mid-arm would be better for me, he was really, really trying to sell me on his setup due to the fact that it uses a rear track bar, and thus has much better "roll center" than the Savvy mid-arm.

....

This would be an interesting area to explore. I've seen 3 link rears. Some of the Currie rock crawler TJs were set up this way. I never understood why the JW mid arm was still a 5 link.
 
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I’m less interested in the low center of gravity and more in how functional the lift is. I know my current one is poorly set up and am trying to figure out if the mid arm is significantly better than the teraflex with the uppers replaced as well.
 
I never understood why the JW mid arm was still a 5 link.

I don't understand it either. Yet he and Chris Sines really, really insist it's "the best" setup for any type of terrain. I'd asked them about the Savvy mid-arm, and they said they've driven a TJ with it plenty of times, and while they do like it, they think that their Jeep West mid-arm was still the better choice.

Of course I can't imagine anyone who would build their own suspension system and then say someone else's is better.

Anyways, I don't regret my decision. There's nothing I've ever bought from Savvy that I wasn't more than impressed with.
 
I remember watching an LJ with the Teraflex long arm continually go into weird occilating wobbles whenever something halfway interesting showed up.

For the drastic difference in arm lengths it’s surprising that it has only been an issue on the really steep climbs. Not as bad as I would have expected.
 
I am surprised that Tera still sells that kit. There are so many problems that manifest themselves with that amount of difference in link length that I am sure you are experiencing. They would have been better off with making the front a radius arm like RE does than to keep the short upper. The rear is whole other story with horrific pinion angle changes just to start.

The biggest problem with their upgrade is their arms are still too long and thus the vertical serpation at the frame is less than ideal. While triangulating the rear does decrease bind in the suspension I still like a track bar for controlling roll center. Unless you have made major changes to increase shock travel you will run out of shock travel well before track bar bind becomes an issue.

So less than ideal but how much improvement to ideal? If I go to a mid arm, how much difference would I see?
 
This would be an interesting area to explore. I've seen 3 link rears. Some of the Currie rock crawler TJs were set up this way. I never understood why the JW mid arm was still a 5 link.
There are a couple of ways to look at that. First question is, does the trackbar give you better roll center? Done correctly, yes it does.

Does the lack of a track bar giving you a better roll center affect the performance enough to deter from any performance criteria except one that would cause you to pick one over the other? That answer is up to you and the fact that the suspension has won the hardest offroad race in the US in class more times than any other rig. You do not run those high speed desert sections, rip over the rock trails and do it back to back to back if there is a performance issue with the suspension design.

The result of the lack of a track bar is a bit more body roll but that is easily mitigated with shocks and swaybars which is what we all run. I'll trade the small bit of body roll for the rest hands down.