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gearhead313
07-03-2004, 10:18 PM
...specificly rear

Im lookin for a new way to mount up my rear shocks and ive seen a wide array of setups and no real info on which ones work better.


this is the 3 basic setups im aware of....the geometry of this really facinates me and i'd like to learn more. So any info'd be great....get ready for some stellar art work....

http://img40.photobucket.com/albums/v123/gearhead313/stock_zj_jig.jpg

http://img40.photobucket.com/albums/v123/gearhead313/forward_jig.jpg

http://img40.photobucket.com/albums/v123/gearhead313/tri_jig.jpg

ya, i know... 2nd graders could do better, but its easier than tryin to find pics online.

Peak ZJ
07-03-2004, 11:54 PM
Why are you unhappy with the stock setup? If you can move your shock mount up even, or just slitely above the bottom of the axle tube(to get it out of the way). To me, the stock setup works well...

BigDaveZJ
07-04-2004, 04:25 AM
My theory is that the Jeep engineers are waaaaaaaaaaay smarter than 99% of us when it comes to this kind of stuff, and on something like that it's just better off left alone.

Krash80
07-04-2004, 05:01 AM
My theory is that the Jeep engineers are waaaaaaaaaaay smarter than 99% of us when it comes to this kind of stuff, and on something like that it's just better off left alone.

Or you could take your panties off and do some math to figure out why triangulating your shocks gives you an assload more travel than the stock setup. I'm gonna ban your ass just for that comment saying that the jeep engineers actually thought ANYTHING through...are you on crack? Have you ever worked on a jeep? :flipoff2: :shock:

Use SOH CAH TOA.....or X, X, X root 2 for a simple 45, 45, 90 traingle....compare the axle travel w/ a vertically mounted shock to one mounted on a 45* angle. Suspension travel was the last thing on the jeep engineers' minds.

-Ron-

Alaska ZJ
07-04-2004, 09:19 AM
Nice double post Krash you fuckin tard.

Alright here is some of what I know.

The closer to verticle you are able to mount your shocks the closer to 100% capabilty you will get.

So that means that if your into highspeed Baja type driving you would greatly benefit from them being mounted vertically or atleast close to.

I absolutyl hate the stock mounting on the ZJ for this reason. I wheel a lot of deep bogs that have everything from VW sized granit boulders to logs to small loose rocks. I have more than once gotten a log jammed into that wheelwell and torched a shock TWICE doing it. The shock also hangs down lower than the bottom of the axle tube. Dumb. I can't even count how many shock brackets I have welded back on.

I moved mine up and into a position like your third picture. It gives a SHITLOAD of travel. Imagine it in your mind. as the wheel rotates around the driveline (like it is "flexin") the shock is not really forced to extend all that much. Some say that this effects your offcamber stability. I just don't by that. Your springs are still in the same place and they are the load bearing part of the suspension not your shocks (Coilovers and Airshocks are a totally different ball of wax)

So If I was going to remount the stock shocks I would try to get them as close to verticle as possible and the bottom mount above the bottom of the axle tube. The angle would be like your third picture. With the tops angled into the middle of the vehicle.

gearhead313
07-04-2004, 10:33 AM
I agree with mounting them triangulated to the inside like the 3rd picture. What i'd like to know now is how far in would you mount them for the greatest amount of travel and still have them work well.

GetoZJ
07-04-2004, 11:15 AM
My theory is that the Jeep engineers are waaaaaaaaaaay smarter than 99% of us when it comes to this kind of stuff, and on something like that it's just better off left alone.
I'm gonna ban your ass just for that comment saying that the jeep engineers actually thought ANYTHING through...are you on crack? Have you ever worked on a jeep? :flipoff2: :shock:
Suspension travel was the last thing on the jeep engineers' minds.

-Ron-

LMAO.

Alaska is right though, about shocks being vertical. Bassetts old rig belongs to a buddy of mine up here, and he had the shocks setup like most toyota people, and I wasn't really impressed with that (or the rest of that booty fab POS). It flexed well, but then again, not much better then my stock SA setup with 30 shocks @6", and RE arms w/ bad bushings :flipoff2:

What I've done in the past, if you think your shocks are limiting you in some way, pull them off in the rear, then flex it until a tire comes off, measure the distance between the body and the top of the tire. On mine, it was the same, telling me the stock location of the shocks was better then the stock location of the control arms and track bar :mrgreen:.

Its way too early, and I shouldn't be writing. I'm bad at the internet.

BMRisko
07-04-2004, 12:15 PM
I agree with mounting them triangulated to the inside like the 3rd picture. What i'd like to know now is how far in would you mount them for the greatest amount of travel and still have them work well.

It depends on the shocks you plan on running.

BigDaveZJ
07-04-2004, 01:27 PM
The thing with shock mounting, it is SOOOO dependent on each person's individual setup that you can't really make a blanket rule for it. Yes, the closer to vertical it is the better. BUT, if it's vertical and no perpendicular to the movement of the axle, it's no good. If I did my shocks like the ones in the 2nd picture, my back end would hop off the ground. In the 3rd pic, it would take too much effort IMO to get the shocks around the gas tank, track, coils, UCA's for IMO not a whole lot of benefit. But like I said shock mounting location is something that is extremely dependent on your setup, the terrain, and your taste. I've even gone as far as examing different mounting planes for the bolts to allow the most seamless expansion and contraction of the shock. Yes, it mounts too low, that sucks, but as far as the general stock mounting location, it works just fine for me and it probably won't get changed until the upper mounting bracket and related sheet metal is in the garbage.

GetoZJ
07-04-2004, 01:36 PM
The thing with shock mounting, it is SOOOO dependent on each person's individual setup that you can't really make a blanket rule for it. Yes, the closer to vertical it is the better. BUT, if it's vertical and no perpendicular to the movement of the axle, it's no good. If I did my shocks like the ones in the 2nd picture, my back end would hop off the ground. In the 3rd pic, it would take too much effort IMO to get the shocks around the gas tank, track, coils, UCA's for IMO not a whole lot of benefit. But like I said shock mounting location is something that is extremely dependent on your setup, the terrain, and your taste. I've even gone as far as examing different mounting planes for the bolts to allow the most seamless expansion and contraction of the shock. Yes, it mounts too low, that sucks, but as far as the general stock mounting location, it works just fine for me and it probably won't get changed until the upper mounting bracket and related sheet metal is in the garbage.


Amen to that. The only reason I'm changing mine in the first place, is due to the whole 9" swap, and while the whole Jeep is on jackstands, I figure I might as well set the shocks up "right", plus the stock mounts probably won't work "right", since the rear axle will be pushed back quite a bit.

Anyhow, an old cliche` comes in on this one, "if it ain't broke, don't fix it". If they're causing you a loss of travel and ride comfort, change them, if they work fine, why bother? (I'm really lazy I just realized)

Kraqa
07-04-2004, 05:43 PM
i thought about triangulating my rear shocks but the problem is that my axle is pucshed back so far that i had to cut off a part of the factory gas tank skid, and there was no room above the axle once the truss and arms were in there. right now i run 33" long shocks in the rear with a 9" long center post in my coil mount. the shocks bottom out about 1/2" befor the coil falls off the post. so in my case it is not really nessisary to triangulate. althoguh my shocks hang about 2" below the axle housing. i could triangulate shorter shocks and bring the axle mounts up out of the way and still gain tones of flex.

Troy
07-05-2004, 06:24 PM
Agreed with everything said here... triangulated shocks provide more travel but provide less dampening ability. When setting up your new shock or mounting system take into consideration the dampening ability of the shock while deciding on what setup to use.

I still run the stock setup and have not experienced any torn off shocks like AlaskaZJ has... I must be lucky so far I have also mounted my shocks below the axle tubes and have not has any problems (only 2 trips out) with destroying the axle tube shock mounts. And I have caught a lot of shit from everybody for mounting them this way. I run the longest Rancho shock available and that's my reasoning (plus spring retainers to hold the springs in during maximum droop).

Raacerx
07-05-2004, 06:59 PM
I run flush mounted brackets on the bottom, just a grade 8 bolt sticking out. It wreaks havoc on the lower shock bushing since the upper part of the shock is mounted behind the axle. I was going to triangulate them (I still have all the neccessary brackets if anyone wants them) but decided that i care to much about the onroad stability. Offroad offcamber situations, I dont see how triangulating them would affect anything. However on the freeway, the difference is quite noticeable for me. If I start ripping the upper mount off, I'll either address it or it'll be another reason to go coilovers.

gearhead313
07-05-2004, 10:41 PM
Excellent input....


I think one of the reasons is im cheap and want to keep my 26.7" rear shox and get the mounted in a fashion that would alow more articulation. I think i could make a triangulated setup work....if i mounted the top a little more forward by mocking up a cross bar not much further ahead of where the upper coil perches are. I just peeked under for now, not sure if there really is room like one of you said.

Could we get some pictures of how some of yins have your shocks done and the results of what that did? I dont know if i'll get to my shocks anytime soon....id like to have more input about keeping the 26.7" shox and trying to get more articulation out of them....

Raacerx
07-06-2004, 03:16 AM
Excellent input....


I think one of the reasons is im cheap and want to keep my 26.7" rear shox and get the mounted in a fashion that would alow more articulation. I think i could make a triangulated setup work....if i mounted the top a little more forward by mocking up a cross bar not much further ahead of where the upper coil perches are. I just peeked under for now, not sure if there really is room like one of you said.

Could we get some pictures of how some of yins have your shocks done and the results of what that did? I dont know if i'll get to my shocks anytime soon....id like to have more input about keeping the 26.7" shox and trying to get more articulation out of them....

for the record, I use 26.7" shocks and I drop the coils at about 25" of extension. Running flush mounts takes away about 2.5" of uptravel so you have that much more droop. Since i run 37s, a lot of uptravel is not neccessary.

http://www.fototime.com/{33B98569-8D26-44ED-8058-21D85DCE30F8}/picture.JPG

gearhead313
07-06-2004, 11:03 AM
see, that is how i'd like to mount mine for now...but right now mine are too far up. When i cut the bracket off the old axle, this is just where they went happily..



that is how it sat on the 4.5" w/ no spacers.


Admin Edit: Pic removed for being huge and everyone's seen it by now. Plus that was killer booty fab!

Alaska ZJ
07-06-2004, 12:19 PM
Gotta love not having the gas tank down low for picture purposes.

http://www.wheelingadventures.com/Northern4x4/iB_html/uploads/post-2-59200-shocksmall.jpg

Cody
07-06-2004, 04:52 PM
Or you could take your panties off and do some math to figure out why triangulating your shocks gives you an assload more travel than the stock setup. I'm gonna ban your ass just for that comment saying that the jeep engineers actually thought ANYTHING through...are you on crack? Have you ever worked on a jeep? :flipoff2: :shock:

Use SOH CAH TOA.....or X, X, X root 2 for a simple 45, 45, 90 traingle....compare the axle travel w/ a vertically mounted shock to one mounted on a 45* angle. Suspension travel was the last thing on the jeep engineers' minds.

-Ron-

What is it with people thinking that suspension travel equates to offroad prowess? Flex is gay. Stability is what you want. Lifting tires isn't a bad thing unless your a pussy and can't take the heat--it's traction that counts and too much flex will adversly effect both your stability and your traction.

As far as the shocks go, the more angle you have, the less they do their job. Sure you get more sweet mall cruisin', rock posin', gay 9" lift stuper-flex, but it will effect how your rig rides. You are reducing the usefullness of the shock--which after all is supposed to obsorb shock.

A little bit of angle is good--it allows you to use more of your suspensions usefull flex (few shocks will be long enough to provide enough compression/extension in a completely vertical setup), but going in at 45's IMO is too far. Why sacrifice handling/performance to gain 1 more inch of useless flex? There is a stability side to the debate too, but I'm probably not the one most qualified to describe it.

Yeah, you see some toy guys do it, and some buggy's have done, but they don't have 5500 lb rigs to suspend.

Cody

Krash80
07-07-2004, 07:05 AM
What is it with people thinking that suspension travel equates to offroad prowess? Flex is gay. Stability is what you want. Lifting tires isn't a bad thing unless your a pussy and can't take the heat--it's traction that counts and too much flex will adversly effect both your stability and your traction.

As far as the shocks go, the more angle you have, the less they do their job. Sure you get more sweet mall cruisin', rock posin', gay 9" lift stuper-flex, but it will effect how your rig rides. You are reducing the usefullness of the shock--which after all is supposed to obsorb shock.

A little bit of angle is good--it allows you to use more of your suspensions usefull flex (few shocks will be long enough to provide enough compression/extension in a completely vertical setup), but going in at 45's IMO is too far. Why sacrifice handling/performance to gain 1 more inch of useless flex? There is a stability side to the debate too, but I'm probably not the one most qualified to describe it.

Yeah, you see some toy guys do it, and some buggy's have done, but they don't have 5500 lb rigs to suspend.

Cody

Not sure why you quoted me with that...all i said is that if you do the math, you'll see that mounting shocks on an angle will give you much more travel then if they're mounted vertically.
I never said flex is the end-all of offroad prowess, however i do disagree with you saying that "flex is gay and traction is what counts." It's pretty tough to get traction with tires that are in the air. Maybe out west when you're wheeling on a really warped parking lot it doesn't matter if you lift tires cause your other tires will still have plenty of traction to keep you moving, but try wheeling a rig with little flex on wet forest trails out east or in the midwest and you'll learn real fast that a lot of times you need all 4 tires touching the ground to keep you moving.

And of course you lose dampening ability when your shocks are angled...the closer they are mounted to horizontal the less vertical stability they provide (take it to the extreme...a shock laying horizontal provides no vertical dampening at all). So if you're concerned about keeping the same vertical dampening ability with angled shocks, it seems to me you could just get stiffer shocks to make up for what's lost by the angle....seems like it would help with lateral stability as well.

Anyway, back to the original question....i'd say that the stock shocks are mounted (well at least the rear are) to work correctly with the arc the control arms move in with the least amount of stress on the bushings, and that just happens to be almost vertical, slightly angled back, and in the same plane as the arc the control arms move in. It would be wise to do the same with whatever suspension you have, but the fact still remains that you'll gain more travel from a given shock the closer you have it mounted to 45*....but no matter what you do, you'll almost always be compromising some other aspect.

-Ron-

Cody
07-07-2004, 11:38 AM
I didn't mean it as a slam against you personally. I've just seen some of the Wazny effect coming back around and I had to squash it before it becomes too common ;)

And you guys act like all I wheel on is slickrock. Lest we forget that where I'm from we get 500 inches of snowfall a year. I know how traction is when it's slippery and If carrying a tire gives the tire on the ground just that little bit of extra contact pressure that it needs....this is why we have lockers.

I'm not saying you need to only have like 10" shocks or anything, but for the suspension most ZJ's run, their is no reason a 12" or 14" shock in the stock (or slightly modified) location can't give enough travel and still dampen the ride.

I have a question--you may be able to compensate for the lack of dampening when shocks are mounted on an angle by running stiffer shocks, but does the angle effect the valving of the shock? Just curious.

Cody

gsh
07-07-2004, 12:04 PM
Alaska ZJ: I noticed that the mounting studs are not parallel top and bottom but rotated along the axis of the shock shaft. Did you have a purpose behind that? Like maybe reducing bushing stress?

Alaska ZJ
07-07-2004, 01:36 PM
Alaska ZJ: I noticed that the mounting studs are not parallel top and bottom but rotated along the axis of the shock shaft. Did you have a purpose behind that? Like maybe reducing bushing stress?

That was my intention. I think it worked out well. I haven't destroyed a bushing yet...lol

paulkeith
07-21-2004, 10:53 PM
if you mount them off of vertical, they will be extended


(length of the shock)/cos(angle they're mounted at)

for 45*, they will be extended 41% more that at vertical, assuming the same height for all the mounts, etc

as far as travel of shocks at angles, again for 45*

1/2 compression of the suspension will only compress the shock 21%

for 30* mount, 1/2 compression will compress the shock 34%

you get the idea.

end math talk.
Paul

gearhead313
08-02-2004, 12:36 PM
if you mount them off of vertical, they will be extended


(length of the shock)/cos(angle they're mounted at)

for 45*, they will be extended 41% more that at vertical, assuming the same height for all the mounts, etc

as far as travel of shocks at angles, again for 45*

1/2 compression of the suspension will only compress the shock 21%

for 30* mount, 1/2 compression will compress the shock 34%

you get the idea.

end math talk.
Paul

that is extremely good information...but what about placement there in associated with the geometry of how the suspension moves? (swing of the axle). I guess im taking about the forward or rearward placement of the top mount?

Nordic1
08-03-2004, 04:29 AM
I do have a question for people that use their ZJ as DD... Is there a way that there could say be two shock mounts either on top or on bottom? Like I could run the stock mounts (best shock absorbing capacity) and then run a second setup for the trail (more travel).

Trancezj
08-03-2004, 09:23 AM
I do have a question for people that use their ZJ as DD... Is there a way that there could say be two shock mounts either on top or on bottom? Like I could run the stock mounts (best shock absorbing capacity) and then run a second setup for the trail (more travel).
Sure, but that'd be a stupid waste of time.




I agree with cody. At first I was going to triangulate them but I quickly realized that I didn't want that much rear travel. Too much in the rear holds you down in holes, and basically works agianst you in a lot of my experience. I like a flexy front, but only a semi flexy rear.

Alaska ZJ
08-03-2004, 10:08 AM
as soon as you unseat the coil your useful flex is done. this is my opinion.

So in reality pinning both sides of the coil is a good idea..

Trancezj
08-03-2004, 10:18 AM
as soon as you unseat the coil your useful flex is done. this is my opinion.

So in reality pinning both sides of the coil is a good idea..

agree/disagree. When there's no weight/pressure on the tire, it's useless. Mine for example in many situations can unseat totally, fall out, and still have presure on it due to the fulcum(sp?) effect from the other tire. But once the other tire has maxed out (hit the top of the fender, got hung on my bumper and put some new "custom siping") then all you have left is gravity pulling your tire down, unless your weight is that way, but 9 times out of 10 in that situation, you're rolling over. Idealy, I'm working on some easy to disconnect limit straps. I love my front flex, it's rediculous. But 75% of the time I don't need that much to stay in forward motion and I feel it's too hard on the jeep to pretzil up like that. I mean, you take the wrong angle and your fuckin' driving on the outside of the wheel.

gearhead313
08-09-2004, 04:20 PM
jesis...just found this on pirate:

http://img.photobucket.com/albums/v123/gearhead313/rearbumper1.jpg

Cody
08-09-2004, 04:30 PM
why even run shocks :shock:

I don't have that much flex, I ramped like a 400 on a 40*. I havn't found a place that I didn't have enough flex to get through. My suspension is kinda funny htough, I run 9" up 5" down in the back, and 4" up 6/7" down in the front. It seems to get it done so I don't play with it.

Cody

Alaska ZJ
08-10-2004, 11:11 AM
Jeez that is gay.

MoonWorks
06-26-2007, 01:38 AM
Obviously, since I brought this old ass thread back...I've been searching around trying to find out a estimate on how long of shocks to run. My rears are completely blown so I'm basically just running springs in the back now. I'm not wheeling again until I get new shocks in but want to now lengths etc...front and rear. I wanted to angle my rears in but after reading this I'm not sure it's worth the work. As long as they're long enough...why not strap it and bump it :). Seriously...you know what I mean.

My rear mounts on the axle aren't stock but they aren't flush on the axle so I will be pushing them up a bit. So I'm thinking I want to build stops about 2.5-3" up so around a 27" rear. My fronts just aren't long enough...good but not quite where I want to be. Don't know what length they are but up travel is fine but they don't droop enough. I haven't measured them yet (been lazy I guess) but wondering what length is common here? Currently, I'm not even getting the top of my 35 below my rocker...still a couple of inches up above it.

MassZJ
06-26-2007, 11:34 AM
Old ass thread, but here is what I have been running and it works well IMO. Bilstein 5150s 29.75" extended are 4-5 years old and in need of replacement. I know they are both fork truck flex shots, but you can see how the shocks work and will never bind no matter how much the axle flexs.

http://www.fototime.com/%7B8B879D22-D511-467E-9CB1-741500C0E3B4%7D/picture.JPG

A few years ago when I had the 8.8 and DD it:
http://www.fototime.com/%7BE710DD49-7B3C-4B33-A9BC-9275708D9F86%7D/picture.JPG

MoonWorks
06-26-2007, 01:41 PM
Are those 29.75 both front and rear?

MassZJ
06-26-2007, 02:07 PM
Are those 29.75 both front and rear?

yup

SOLITUDE
06-26-2007, 03:01 PM
lets see the unibody-side mounts you fabbed up.

AgitatedPancake
06-26-2007, 03:42 PM
its probably just a tube spanning between the two "frame" rails, with bolts sticking out for the shocks to mount to. Thats a pretty easy way to do it.

jsteves
06-26-2007, 03:44 PM
I doubt they are fabbed. He is running Clayton's longarms and Clayton sells a rear crossmember to triangulate the rear shocks.

MassZJ
06-26-2007, 04:51 PM
It is a piece that Clayton fabbed up for me and now now stocks. It is pretty simple to fab one up too. A piece of L channel with 2 bolts welded to it that spans the "frame" rails just fwd of the fuel tank.

Now that I have a cage I am going to span that and run the shocks through the floor, since the "frame" rails are starting to get tired.

Also forgot to add, limit straps are your friend. If you dont run them you'll be dropping coils all the time.

jsteves
06-27-2007, 12:55 AM
Not that it is a good idea. But a 12" travel shock with that clayton's setup keeps the coils in and allows it to flex to the point the rear springs are unloaded...no straps.

MassZJ
06-27-2007, 01:55 AM
Yea, it isnt a good idea to use a shock as a limiting device, up or down. Trust me I know. One day of wheeling with show you that.

I never understood why people are afraid/dislike limiting straps and bumpstops. Seems like an overlooked part of suspension modification.

jsteves
06-27-2007, 11:29 AM
I the rear I use the cheap shocks that Clayton sent as a bumpstop...they have little rubber bumps stops at the top.

ELLLLLIOTTTTT
06-28-2007, 12:48 PM
This is a great thread. Good to see alot of old names.

8WR_ZJ
07-08-2007, 08:29 PM
yep this a good one. i just finished up la's and full widths on mine and this is what i am getting into this weekend. i believe i am going to inboard them a bit not to crazy it is my dd. who else has pics i just like to look!!

MoonWorks
07-09-2007, 01:35 PM
I still haven't decided exactly what I'm going to do yet. I'm thinking about just getting some 27" shocks for the rear...moving the tabs on the axle up flush behind the axle tube and calling it a day. I'm still considering moving them inside the "frame" rails but I won't be setting them at any extreme angles.

96_zjlarado
07-10-2007, 08:52 AM
here's a few of mine. not the best pics, but they kinda show what jsteves was talking about with the clayton's inboard shock mount that goes between the frame rails. I don't know if it came with my high clearance axle bracket kit or the long arms being that both axle bracket kits and the LA's showed up the same day.


http://img185.imageshack.us/img185/6540/dscf1395ff6.jpg

you can kinda see the cross bar here. the bolts have the green tape on them.
http://img180.imageshack.us/img180/3144/dscf1316jr3.jpg

The only thing i had to do to my stock skid was bend the corner up on the driver's side to make room for the shock. I moved my axle back almost 2 inches, so if you kept the axle in the same location, you might not have to do it. the passenger side was all good because of the recess it has for the exhaust.

96_zjlarado
07-10-2007, 09:01 AM
found a pic of the shock cross bar. it's right under the axle truss.

http://img291.imageshack.us/img291/3559/dscf1260hm2.jpg

MassZJ
07-10-2007, 09:23 AM
That's a nice setup.