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Limited Grip in rear after coilover Installation - Stance GR+

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Old 08-26-08 | 10:58 AM
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Limited Grip in rear after coilover Installation - Stance GR+

Hey guys,

I installed a set of slightly used coilovers the other week and just got a chance to drive the car around the block. I noticed some things which have me concerned.

First, it seems like the rear right wheel has almost no grip any more, driving in my gravel driveway it was spinning from time to time. More pronounced is when making right hand turns on the road( like from a stop sign) the rear right wheel is spinning under normal acceleration.

I noticed that when I initially installed the coilovers that the ride heights were very different from side to side in the back with the coilovers set the same and the car on the ground. The drivers side was much lower( more than 1" lower) when they were both bottomed out so I raised the drivers side up to match the passengers side. In doing so I noticed the big difference in the wheels when the car is up on jack stands, the drivers side wheel hangs much lower than the passengers. I imagine this is because the passenger's coilover is still bottomed out and the drivers side is jacked up to match when it's on the ground.


So i have two things bugging me.

1) I am concerned about the fact that I have to have once side way jacked up and the other bottomed out to have the ride height equal, and it's not even that low in the rear once evened out.

2) I am even more concerned by the loss of traction in the right rear wheel, it was never like this before the coilovers and I haven't heard any similar stories.


I understand that the car's weight is not even from side to side but I was really not expecting it to come out so lop sided. With the KYB's and Racing beat springs it was level from side to side and at least as low in the back as with the coils.

Any insight or advice would be greatly appreciated.
Old 08-26-08 | 11:35 AM
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Are you sure those shocks aren't blown and that the spring rates are correct and the same side to side?
Old 08-26-08 | 11:38 AM
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actually the passengers side does have a blown damper, the right rear is making a tom of squishing noises while the other corners are silent.I just realized this during the same test drive and will be getting a new damper from Stance.

Would a blown damper make it rest higher than normal? I had thought it would sag with the blown damper.
Old 08-26-08 | 03:57 PM
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to lower the car- did you compress the springs? or did you spin the bottom of the coilover up/down?
if you compressed the spring (preload) to set ride height they will hang differently, and if you compress them pretty far (like over and inch or whatever) the car will start acting really weird.
Old 08-26-08 | 04:00 PM
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what condition are the bushings in the rest of your suspension in? Has your differential ever been serviced or replaced? I'd suggest you make sure you check your bushings, remove any preload in any corner, even out the ride height, and then get an alignment. Squishing noises are usually worn bushings in my experience.
Old 08-26-08 | 04:02 PM
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No, I reset the preload to the suggested starting point by loosening the spring, then tightening by hand followed by turning twice with the wrench.

To adjust ride height I simply turned the bottom of the coilover to increase/decrease the gap between the lower shock mount and the spring.
Old 08-26-08 | 04:04 PM
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The diff is new, the suspension bushings are okay. The squishing noise is obviously coming from the rear driver's side coilover - I am positive it is blown because it makes all sorts of noise like a blown shock when driving, the other corners are fine.
Old 08-26-08 | 08:11 PM
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Can you measure spring length when compressed, like with you car up on ramps? it really sounds like the springs are not even side to side. Not your spring preload, the actual springs.

Also, I believe if one of the struts was de-gassed, like from a blown seal, it could affect your ride height, thought by .5in, i dunno.
Old 08-26-08 | 09:26 PM
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I can look into it but do you think they would end up different lengths if thjey started the same uncompressed? What would that mean, maybe different spring rates??
Old 08-26-08 | 11:44 PM
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One potential problem is that you may have it setup wrong and the wheel's running out of droop travel and becomming unloaded.


Originally Posted by Josh18_2k
to lower the car- did you compress the springs? or did you spin the bottom of the coilover up/down?
if you compressed the spring (preload) to set ride height they will hang differently, and if you compress them pretty far (like over and inch or whatever) the car will start acting really weird.
Unless you compress them to the point that the car's lacking droop travel, or worse yet, so that it doesn't compress at all under load, then preload is fine.
Old 08-27-08 | 12:23 AM
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thats what i was talking about- preloading past the the static corner weights. the car would be rock hard...

anyway sounds like thats not the issue. maybe a bunch of pics are in order..
take some of the coilovers with car on jacks, on teh ground, whatever.

Originally Posted by Black91n/a
One potential problem is that you may have it setup wrong and the wheel's running out of droop travel and becomming unloaded.




Unless you compress them to the point that the car's lacking droop travel, or worse yet, so that it doesn't compress at all under load, then preload is fine.
Old 08-28-08 | 01:25 PM
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Okay, well I reset the preload according to Rishies instructions so i hope we're okay there.

I will post pics pf the car on the ground and on a jack, you can clearly see the difference in wheel gaps and shock lengths in order to equal wheel gaps. I will take the pics tonight when I get home.

I'm ordering the replacement damper later today as well.

Thanks for helping me out here, I really appreciate it.

-NJGB
Old 09-05-08 | 12:40 PM
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Update with Pics

Okay well I replaced the damper on the passenger's side because I thought it was blown. The new damper is a bit shorter, Stance says it allows for more adjustment, and then reset each side. I still have the passenger's side at the lowest setting and had to raise the driver's side about 2" to get them even.


Here are the final wheel gaps with it resting on the ground-

Driver's Side on Ground



Passenger's Side on ground




Because the new damper is a bit shorter it allows the passenger's side to sit lower at it's lowest point, low enough that I would be very happy with it's ride height now. But I still had to jack up the driver's side to get the wheel out from under the fender and equal to the passenger's side. I noticed that when I jack up the car the driver's side wheel gap actually changes while the passenger's side stays about the same as when it is on the ground. I have driven it around a bit and it seems to have a bit more grip but still seems like the passenger's side wants to spin easily.

I know I have to have an alignment but I'm wondering what why each side is so different and what could be wrong with the other suspensions components to cause this??

Here's what the rear looks like up on a jack, note the difference in shock length and wheel height.


Driver's Side up in the Air





Passenger's Side up in the Air


Old 09-05-08 | 04:56 PM
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wtf that is so not right.. take pics of the coilovers on the car.
it still looks to me like you preloaded the **** out of them..
and all the way lowered, the tire should be up inside the fender.
Old 09-05-08 | 09:21 PM
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You have only about 3/8" of droop travel on that side. That is not right, you've preloaded it way too much and that's the problem. Try evening out the ride heights with shock body adjustments instead.

I wonder if part of the problem might not be severly mismatched springs, with one being significantly softer.
Old 09-06-08 | 12:43 AM
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I know it's not right. I don't know whats wrong in specific though.

The springs aren't it though, I'm not preloading the springs too much, I reset the preload multiple times with no improvement. I'm not adjusting ride height via the upper spring seat.

The only way I have adjusted ride height is to move the lower shock mount so far.





I
Old 09-06-08 | 11:46 AM
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Ok sorry to be a off-topic here but I never knew Kumho tires were made in Korea.
Old 09-06-08 | 02:02 PM
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Geez blizz, I was actually planning on buying the Kumho Ecsta MX but ended up with these Ecsta ASX instead. Oh well, next time I'm getting the MX though.


Here's some more pics and measurements this morning. These are the same settings as the pics above. I noticed the length of the springs was a bit uneven here so I corrected it so both were the same at 7.75".

Driver's side-


Spring-


Shock-


Hub to fender along the line of the strut-





Passenger's side-


Spring-


Shock-


Hub to fender along the line of the strut-







I then made the passenger's side shock equal to that of the drivers side to see what would happen, so I set them to the exact same spring length and total length. When I lowered it the passenger's side wheel gap was huge, much more than the drivers side.

In an attempt to see if the springs were different or bad I took the coilovers completely out of the car and reinstalled them each on the opposite side of the car. So with them set exactly the same and installed on the opposite side of the car, I again lowered the car and was surprised to see that the car sits the same as before. The passenger's side is still higher.

When the suspension was removed from the car I took the opportunity to move the hub around. The trailing arms seem to be moving freely and equally on both sides and I didn't see anything broken or obviously bent.


I am at a complete loss here.


Last edited by NJGreenBudd; 09-06-08 at 02:04 PM.
Old 09-06-08 | 03:57 PM
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I would always replace shocks/struts as a pair respective to front and back.

I am very surprised Stance did not also advocate this- especially since they changed the construction of the damper between the original and the replacement.

What is likely is that the passengers side was depressurized and missing shock oil, hence the squishing noises.

Most likey, you replaced it with a new unit, only to find the drivers side is also depressurized though not missing oil, hence no noise.

Evidence pointing to this is the different ride heights despite your *finally* setting the springs and shock body lengths the same.
Old 09-06-08 | 04:21 PM
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Has the car ever been in an accident? Maybe the chassis is a bit bent?

My advice would bo to take it to a race shop and get them to have a look and corner weight the car (if they have a spring rate tester I'd get them to test those springs to be sure, since cheap springs are much more likely to be mismatched, even if they're supposedly the same). Ride heights might not be 100% even, but as long as the corner weights are good, you're good to go.

This certainly doesn't make me want to be a stance customer or buy any used suspension any time soon. Hope you get it worked out.
Old 09-06-08 | 04:48 PM
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Originally Posted by BLUE TII
I would always replace shocks/struts as a pair respective to front and back.

I am very surprised Stance did not also advocate this- especially since they changed the construction of the damper between the original and the replacement.

What is likely is that the passengers side was depressurized and missing shock oil, hence the squishing noises.

Most likey, you replaced it with a new unit, only to find the drivers side is also depressurized though not missing oil, hence no noise.

Evidence pointing to this is the different ride heights despite your *finally* setting the springs and shock body lengths the same.
But when I reinstalled them on the opposite sides the passenger's side was still higher than the drivers side.
Old 09-06-08 | 04:54 PM
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I believe the car is straight, the front fender was replaced by the previous owner but I haven't seen anything to make me think the frame is bent. I will look around for a shop to check it out if I can't figure it out I guess.

Even if I got different suspension I might still have the same problem if it's really something wrong with the car.
Old 09-06-08 | 05:10 PM
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I appologize, I misread the italicized section the first time through and thought you checked the springs by changing them side to side.

Changing the entire damper/spring combo side to side with same results does point to another issue at play.
Old 09-06-08 | 06:29 PM
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Did you only replace one damper? Since I didn't supply these i'm a little in the dark. From your posting it appears you only replaced one side. If that's the case we can go through the steps to make sure it's set at equal preloads and ride heights. I'd almost suggest doing this.

1. pull off both rear dampers from car.
2. reset spring preload If 8" spring, just put 1/8" of preload to just help it maintain its position.
3. Once both dampers are off the car with reset preload place them side by side and match up their lengths identically. ***Remember you need to maintain approx 1" of threaded casing INSIDE OF THE LOWER BRACKET. Macpherson inverteds should have about 2" of threads inside bracket.***
4. Make sure ground is flat with a Level.
5. After you've done that put them back on the car.
6. Drop ebrake, roll forward and back. Make sure it's settled.
7. Report Back.

If it's still off kilter then they might have different spring rates on either side, spring is bad, or damper is bad.

In any case PM me or reply here. I might even have to talk to ya over the phone to see exactly what's what and then i can go through the proper order of installation and spring preload settings.

Rishie
Old 09-06-08 | 10:08 PM
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i think he said that he swapped the coilovers back and forth, and the passenger side sat the same every time.
if this is the case, you may just wanna find another rear end dropout from another car. on my first FC, after it went over a curb.. i replaced almost everything under the rear end, and everything appeared perfect, but it had nasty positive camber on one wheel. the rear suspension can do some really wierd stuff with the slightest bit of damage.

you should be able to find a complete dropout from another car for cheap. aside from the diff and brakes, the rest of the stuff has almost no value.


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