Maximum Articulation

I'm currently at 4", 2 1/2" of new springs and another 1 1/2" using longer shackles and front coil spring spacers. I'm wondering what the best way is to get maximum articulation without going up more than an inch or so. I'd prefer not to go up any higher at all, since I'm in a wheelchair, but I've seen a long arm kit that sits at 5.5" and it seems that a long arm suspension would give the greatest articulation. Is there any way to do that at 4" or is that a waste of time?

By maximum articulation I mean that I want the most droop with the least compression.

Thanks,
Robert

Read this, and also follow the first link at the bottom to Ed Stevens' page.

http://www.jeepin.com/features/superflex/index.asp

VERY GOOD stuff

Look into the things that limit articulation!

Brakelines
Shocks
Swaybars
Trackbar type and both mounts
Control arm type,the lower axle mount and the upper body tab

XJWheelie said:

I'm currently at 4", 2 1/2" of new springs and another 1 1/2" using longer shackles and front coil spring spacers. I'm wondering what the best way is to get maximum articulation without going up more than an inch or so. I'd prefer not to go up any higher at all, since I'm in a wheelchair, but I've seen a long arm kit that sits at 5.5" and it seems that a long arm suspension would give the greatest articulation. Is there any way to do that at 4" or is that a waste of time?

By maximum articulation I mean that I want the most droop with the least compression.

Thanks,
Robert

Click to expand...

Articulation comes from tuning the suspension regardless of the lift height. You don't necessarily get more articulation with more lift height. The biggest things affecting articulation are the looseness of the rear springs, any binding in the front suspension or steering, and the length of the shocks. Getting the shock length right is the biggest thing, few off the shelf lifts come with the best length shock. It's always recommended to buy a lift without shocks, install the lift, go out and flex it up and measure for correct shock length, then order the right shocks.

The front of an XJ with articulating control arms and a track bar and drag link that don't bind will normally droop till the shocks fully extend. So, the key is to have as long a shock as possible. The issue with longer shocks is that with more extended length you also get longer compressed length so the key is to have the longest compressed length that will work for your particular suspension. Find the longest extended length shock with the compressed length that you need by looking through the shock specs charts, and you will probably have to search a number of different brands to get the best length shocks for your application.

Long arms don't give better articulation. They provide a better arc for the axle to swing through, which can give a better ride and can make some vertical ledges easier to climb, but they won't give more articulation. The shock length determines articulation, with either a short or a long arm.

To expand a bit on Goatman's post:

He refers to "... a track bar and drag link that don't bind ..." You might not have picked up on why he wrote that: The OEM track bar DOES bind. That's why many folks advise disconnecting it when installing taller front springs. It's possible to grind away a bit of the axle bracket to allow more droop, and the "heavy duty" frame brackets from aftermarket manufacturers like Rusty and Rubicon Express allow more angular movement that the stock tie rod end connection.

Long arms don't have anything to do with lift height. I can put a long arm kit on my XJ at stock height. If I don't change anything else, it won't affect my articulation at all.

In the rear, you can get more droop out of leaf springs by removing the clips that hold the leaves together. However, then you face the very real probability that in a short time the leaves will start to "fan" out. Those clips keep everybody pointing in the same direction. There are ways to make clips that allow more leaf separation (and thus droop) than stock yet keep the leaves aligned. Many years ago J. C. Whitney sold a set that were just a square u-bolt and a flat plate -- but instead of socking the plate down tight, the legs on the u-bolt were extended and there was a coil spring between the plate and the nut. When droop was needed, the little coils would compress and allow the leaves to separate.

Overall, I think (someone correct me if I'm wrong) you'll get more droop from a true 4" leaf spring than you will from a 2-1/2" spring and 1-1/2" shackles. In order to compensate for the additional arch, the taller spring has to have a longer main leaf. That should allow it to droop more when unloaded. If you're more interested in droop than "stuff," you want springs and shackles that sit at rest with the shackle pointing toward the rear rather than vertical. That allows the shackle more swing as the spring droops.

Hope this helps.

Eagle said:

Overall, I think (someone correct me if I'm wrong) you'll get more droop from a true 4" leaf spring than you will from a 2-1/2" spring and 1-1/2" shackles. In order to compensate for the additional arch, the taller spring has to have a longer main leaf. That should allow it to droop more when unloaded. If you're more interested in droop than "stuff," you want springs and shackles that sit at rest with the shackle pointing toward the rear rather than vertical. That allows the shackle more swing as the spring droops.

Hope this helps.

Click to expand...

Actually, the flatter spring will normally droop more. The spring with more arch is already drooped more than a spring with less arch, so has less room for additional droop. Also, the longer shackle helps droop by having a longer arc as it moves downward, basically letting the rear eye of the spring travel further inward (a little more downward arch) than a shorter shackle would. Any advantage would depend on the angle of the shackles, but in the most general sense the longer shackle will allow for more droop.

Unfortunately, all taller springs don't have longer main leafs.

Just realized that something I wrote could be taken incorrectly and cause MAJOR problems:

Eagle said:

He refers to "... a track bar and drag link that don't bind ..." You might not have picked up on why he wrote that: The OEM track bar DOES bind. That's why many folks advise disconnecting it when installing taller front springs. It's possible to grind away a bit of the axle bracket to allow more droop, ...

Click to expand...

When I wrote "... many folks advise disconnecting it when installing taller front springs" I meant during the installation process, not to leave it disconnected. If the track bar isn't connected the axle won't stay centered under the chassis and you can't steer.

Y'all knoew that already, right? :anon:

Eagle said:

Just realized that something I wrote could be taken incorrectly and cause MAJOR problems:



When I wrote "... many folks advise disconnecting it when installing taller front springs" I meant during the installation process, not to leave it disconnected. If the track bar isn't connected the axle won't stay centered under the chassis and you can't steer.

Y'all knoew that already, right? :anon:

Click to expand...

Yeah, we figgered it out.

Revolver Shackles

One other thought; what about using 4" lift springs in the rear teamed up with some kind of revolver shackle, such as the one that TerraFlex makes?

Also, any recommendations on who makes the best springs, front and rear to allow maximum droop?

Thanks again,
Robert

These worked for me on a couple of my lifts!!

Goatman

Hey, you described what I am about to do with my RE4.5. I was wondering about the front shocks; Is there a concern with getting a shock that is too long? Unseating the coils or something? I was thinking that if I get front shocks that are just short enough when compressed so as not to bottom out when fully stuffed, they may be too long.
Does that make sense?

If you size your shocks correctly,you may un-seat a spring but thats not a problem unless your using alot of spacer for lift!

Thanks RCP, Well I am using the RE 4.5" coils with just the stock isolator so I guess it's not a big concern, right?

spacers

Currently I'm using a 2.5" suspension lift spring with a 1.5" spacer. Common sense tells me that I would be able to get more droop with a 4" spring. Is this correct?

Thanks,
Robert

Re: spacers

XJWheelie said:

Currently I'm using a 2.5" suspension lift spring with a 1.5" spacer. Common sense tells me that I would be able to get more droop with a 4" spring. Is this correct?

Thanks,
Robert

Click to expand...

Possibly more droop without unseating the coil, but it depends on the free length of the coil.

The factory coils are ~18 inches long without a load (the free length). Aftermarket coils run from 18 to 24-inches when unloaded. The longer coils will remain seated longer.

The usual 4" lift coil is about 20-21 inches long, the same unloaded length as most 2.5-inch coils with a 1.75 inch poly spacer and two rubber isolators. (18+.5+1.75+.5=20.75). Both combinations provide ~4" lift increase, and both unseat with the same shock extension.

The shock extension is the limit for most XJ's, so matching the longest shock to the desired droop and compression range will provide the best balance without additonal height. Look at longer shocks, and altered mounts, before thinking about swapping springs.

Something to consider!The XJ is more front friendly to begin with,adding some spring rate to the front will make the rear work more!