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Building a Bumper?Ruffstuff Axle Simple Swap Kit!~Artec JK 1 TON SWAP~

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Unread 07-13-2012, 04:02 AM   #1
stevsand77
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zj control arms

so i have a 3.5 inch lift. We bought the kit about 5 years ago before they started selling these kits with control arms, so all it came with was front springs and all four shocks. The jeep still has the stock control arms on it. Would adding new control arms give it a better ride?

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Unread 07-13-2012, 04:05 AM   #2
Canyon411
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A resounding YES. The ride quality with that much lift on shortarms is going to be horrid!! And you would be maxing your articulation way too fast.
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Unread 07-13-2012, 05:33 AM   #3
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In terms of ride quality: No. Short arms are short arms. If anything the aftermarket arms will degrade ride quality because they are stiffer.

The biggest factor in ride quality is the shocks. The benefit of aftermarket controls arm is that they are stronger, offer more flex (if they have some sort of flex joint), and allow you to dial in pinion angle and caster (if they are adjustable.)
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Unread 07-13-2012, 07:21 AM   #4
KingtheZJ
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Quote:
Originally Posted by Technohead View Post
In terms of ride quality: No. Short arms are short arms. If anything the aftermarket arms will degrade ride quality because they are stiffer.

The biggest factor in ride quality is the shocks. The benefit of aftermarket controls arm is that they are stronger, offer more flex (if they have some sort of flex joint), and allow you to dial in pinion angle and caster (if they are adjustable.)
agreed
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Unread 07-13-2012, 07:31 AM   #5
Canyon411
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Quote:
Originally Posted by Technohead View Post
In terms of ride quality: No. Short arms are short arms. If anything the aftermarket arms will degrade ride quality because they are stiffer.

The biggest factor in ride quality is the shocks. The benefit of aftermarket controls arm is that they are stronger, offer more flex (if they have some sort of flex joint), and allow you to dial in pinion angle and caster (if they are adjustable.)
True, shocks would help with rq. Articulation (suspension travel) would be fairy limited with the short arms as alot of their travel is now occupied with the new ride height. What kind of shocks came with your kit?
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Unread 07-13-2012, 07:34 AM   #6
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the ride will be a little better because you can get the castor of the axle back where it should be. a huge difference no but it will help having the right length control arms. However the gains in wheel travel with say a savvy, rokmen, clayton ect style flex are will be huge over the stock arms.
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Unread 07-13-2012, 11:03 AM   #7
PolkaPower
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If all the rubber bushings in the stock arms are worn out then the new arms will make a difference in ride quality.
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Unread 07-13-2012, 11:49 AM   #8
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Originally Posted by PolkaPower View Post
If all the rubber bushings in the stock arms are worn out then the new arms will make a difference in ride quality.
Good point. Although the bushings in most aftermarket arms suck compared to the stock bushings.
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Unread 07-13-2012, 12:05 PM   #9
PolkaPower
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Yes indeed. I prefer stock rubber bushings. My RE arms had the stock rubber in them. They were nice.
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Unread 07-13-2012, 12:10 PM   #10
93zjer
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having the short (stock) control arms is going to affect your caster, so handeling will be affected not really the ride. That is to say if you think of the ride as how bumpy, stiff or soft the jeep feels. That's a matter of shocks and springs.

PolkaPower, again in the terminology I'm familiar with, worn c.a. bushings effect the handling much more than the ride.
I don't understand what Technohead is talking about, "If anything the aftermarket arms will degrade ride quality because they are stiffer". Whats stiffer, the bushings?
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Unread 07-13-2012, 12:13 PM   #11
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I could feel more bumps with my trashed disintegrated bushings and had way more body lean as well so I think it affects both. With stock arms and 3.5 the control arms being at such and angle are going to be taking all those potholes and transferring the hits right into the body instead of cycling up and down like at stock height.
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Unread 07-13-2012, 01:34 PM   #12
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Originally Posted by 93zjer View Post
. . . I don't understand what Technohead is talking about, "If anything the aftermarket arms will degrade ride quality because they are stiffer". Whats stiffer, the bushings?
I am talking about the control arms themselves, not the bushings. Nothing is perfectly rigid so you can consider the control arm itself as a spring. The stock control arm is stamped from 14 gauge sheet metal and provides a certain level of "spring" on its own. Aftermarket control arms are much stiffer, hence less spring and harsher ride.
All clear now?
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Unread 07-13-2012, 02:42 PM   #13
Timo_90xj
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Will aftermarket short arms make a huge difference? No.
Will they make the ride and handling better? In my experience, yes.
However, one of the biggest gains over stock arms is you don't have to worry so much about bending the crappy stamped arms which can handle no rock rash or big hits at all


Quote:
Originally Posted by Technohead View Post
I am talking about the control arms themselves, not the bushings. Nothing is perfectly rigid so you can consider the control arm itself as a spring. The stock control arm is stamped from 14 gauge sheet metal and provides a certain level of "spring" on its own. Aftermarket control arms are much stiffer, hence less spring and harsher ride.
All clear now?
True, but flex joints give you the "spring" required what the stock flexy CAs would do under a load that would make the arms twist. Driving on the roads, CAs mostly transmit only longitudinal forces anyway, so what affects ride quality and NVH the most are the CA angles and bushings used - not the amount of flex the arms provide.

As for the bushings, flex joints do have poly bushings but if the aftermarket arms have stock- style clevite rubber bushings on the other end NVH does not really increase much at all IMO. Most of the time, we're running MTs or ATs anyway which will create quite a bit of NVH anyway The bigger tires with more sidewall on the other hand do absorb some of the energy from sharp bumps that stock tires wouldn't, so they do some good as well


As you mentioned, a short arm lift is a short arm lift. With 3.5" of true lift, no short arm lift will ride as good as the ZJ rode when it was stock, no matter what kind of CAs one is running. Aftermarket arms adjusted to some WB stretch (~1.5 on both ends) will ride better than stock arms, but one shouldn't expect any miracles
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Unread 07-13-2012, 02:55 PM   #14
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Quote:
Originally Posted by Timo_90xj View Post
True, but flex joints give you the "spring" required what the stock flexy CAs would do under a load that would make the arms twist. Driving on the roads, CAs mostly transmit only longitudinal forces anyway, so what affects ride quality and NVH the most are the CA angles and bushings used - not the amount of flex the arms provide.
I would agree that if the bushings are really soft (like the OEM bushings) then the stiffness of the control arm becomes negligible. In the stock configuration with horizontal control arms most of the vehicle weight is supported by the springs and virtually none is felt by the controls. Once the vehicle is lifted this is no longer true. The control arms essentially become a very stiff spring in parallel with the coil spring which is why ride quality degrades. Under these conditions there is no way that aftermarket control arms, which typically have very stiff flex joints and/or harder bushings, could improve ride quality compared to stock. Either way, the compressive stiffness of the control arm itself is a second-order effect.
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Unread 07-13-2012, 03:21 PM   #15
Timo_90xj
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Quote:
Originally Posted by Technohead View Post
I would agree that if the bushings are really soft (like the OEM bushings) then the stiffness of the control arm becomes negligible. In the stock configuration with horizontal control arms most of the vehicle weight is supported by the springs and virtually none is felt by the controls. Once the vehicle is lifted this is no longer true. The control arms essentially become a very stiff spring in parallel with the coil spring which is why ride quality degrades.
Yeap, I do know that very well.

Many of the aftermarket arms do use stock bushings at the other end, so in that sense both stock arms and aftermarket arms are on par with each other. Like I wrote, if you increase the WB some it does help on reducing the CA angles -> improves ride quality over stock arms on a lifted Jeep. My personal experience from three different lifted Jeeps lifted to a few different heights between 1.75"-4.5" on short arms is that aftermarket short arms result in better ride quality and handling when compared to stock arms. But a way bigger difference was when moving to long arms first on 3.5" lift and later 4.5" I'd never lift a Jeep more than 3" lift on short arms, such big was the difference with long arms

I do completely agree with you that any lifted Jeep will have reduced ride quality compared to stock because of the increased CA angles. Not even a long armed Jeep can be as good as a stock Jeep - but at best very close to it
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