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MM Road and track lowering springs not lowering?

  • Thread starter Thread starter impropernick
  • Start date Start date Aug 30, 2021
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    lowering springs suspension
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impropernick

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Aug 30, 2021
#1
  • Aug 30, 2021
  • #1
Hey everyone, I'm doing a crap ton of suspension work and an engine swap to my 82 4cyl so the car isn't street worthy right now, but I just put in my rear maximum motorsports road and track lowering springs with J&M height adjustable lower control arms and it definitely doesn't look like it really dropped the car the amount it should have which is .75"-1.25" on the rear...I just mocked up the wheel with the rotor to see how it looked, so no caliper or anything.

Now, this weekend I installed a newly built 8.8 rear diff, J&M adjustable upper (adjusted to stock length) and J&M Weight Jacker lower control arms and the MM road and track lowering springs. The wheel/tire combo is SVE r350 18X9 and nitto nt555 g2 265/35/r18 in one pic, and the stock setup in the other pic. The differential is jacked up with a floor jack so the weight of the car should be on the springs and nothing is torqued yet, and the pig tail on the springs are at 9 o'clock per install instructions. The upper and lower control arms SEEMED to articulate just fine when I was jacking the differential up and down, however I did have a pretty hard time getting the lower passenger side into the differential and was running low on grease, but it was still lightly coated. The weight jacker control arms are also supposed to give additional height adjustment from 1" drop to 2" lift but they are bottomed out...

If anyone could give me some ideas as to what might be going on I would be very appreciative! Thanks

​

​

 

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impropernick

Member
Jan 4, 2021
52
11
18
New Hampshire
Aug 30, 2021
#2
  • Aug 30, 2021
  • #2
impropernick said:
Hey everyone, I'm doing a crap ton of suspension work and an engine swap to my 82 4cyl so the car isn't street worthy right now, but I just put in my rear maximum motorsports road and track lowering springs with J&M height adjustable lower control arms and it definitely doesn't look like it really dropped the car the amount it should have which is .75"-1.25" on the rear...I just mocked up the wheel with the rotor to see how it looked, so no caliper or anything.

Now, this weekend I installed a newly built 8.8 rear diff, J&M adjustable upper (adjusted to stock length) and J&M Weight Jacker lower control arms and the MM road and track lowering springs. The wheel/tire combo is SVE r350 18X9 and nitto nt555 g2 265/35/r18 in one pic, and the stock setup in the other pic. The differential is jacked up with a floor jack so the weight of the car should be on the springs and nothing is torqued yet, and the pig tail on the springs are at 9 o'clock per install instructions. The upper and lower control arms SEEMED to articulate just fine when I was jacking the differential up and down, however I did have a pretty hard time getting the lower passenger side into the differential and was running low on grease, but it was still lightly coated. The weight jacker control arms are also supposed to give additional height adjustment from 1" drop to 2" lift but they are bottomed out...

If anyone could give me some ideas as to what might be going on I would be very appreciative! Thanks

​

​

Click to expand...
Can't figure out where to edit, but I meant to say the spring pig tails were at 6 o'clock per MM install instructions, NOT 9
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#3
  • Aug 31, 2021
  • #3
The jack stands don't appear to be free under the car. That would mean all the weight is not on the rear and the springs. If the interior is out or back seat and spare removed it'll make a slight difference.
 

impropernick

Member
Jan 4, 2021
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Aug 31, 2021
#4
  • Aug 31, 2021
  • #4
90sickfox said:
The jack stands don't appear to be free under the car. That would mean all the weight is not on the rear and the springs. If the interior is out or back seat and spare removed it'll make a slight difference.
Click to expand...
Thanks for the reply, I did jack it up JUST enough to get it off the jack stands, since there's no need to have it 6" above them haha
 

KRUISR

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Apr 16, 2015
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Aug 31, 2021
#5
  • Aug 31, 2021
  • #5
Can you get a pick from this angle...



My set up at the time was reinforced stock arms with rear mount relocated down 1.75" and stock rear springs. Here was the car's stance with no interior, gas tank or side glass (doors had glass and hatch with no glass).

 
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impropernick

Member
Jan 4, 2021
52
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New Hampshire
Sep 1, 2021
#6
  • Sep 1, 2021
  • #6
Kruisr, how's this? I got several pics of similar and different angles. What are you looking for in the pics?
 

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KRUISR

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#7
  • Sep 1, 2021
  • #7
Thanks for the pics. The main reason is it helps to identify if something seems off, which to me it doesn't.

Have you tried undoing one of the upper control arms to see if you are experiencing any suspension bind?

The line through the lower control arm mounts relative to the bottom of the spring looks like you have the base of the spring lower than stock, which should be helping you. Makes me think suspension bind. What rear upper bushings are you using (on the axle housing)?
 

impropernick

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Jan 4, 2021
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New Hampshire
Sep 1, 2021
#8
  • Sep 1, 2021
  • #8
Thanks for the response, I'll have to check the control arms for binding this weekend when I can tear everything apart again lol. But I was thinking that because the upper control arms were flattening out and seeming to move along with the the jack that it wouldn't be binding. Would they still move? or would they MOVE, just with requiring more force? And what would confuse me more is that none of the bolts are torqued haha. Also, The axle housing has just stock replacement rubber bushings
 

KRUISR

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#9
  • Sep 1, 2021
  • #9
The reason I asked about bushings is because when I installed poly upper bushings in my axle I had to adjust the metal sleeve in the housing so the upper arm didn't need side loading to get installed. Poly bushings are usually flanged on one side, so sleeve needed to move the thickness of the flange.

When you disconnect one upper arm, it should stay in line with where you just pulled it off. If it shifts to one side or another you will have some amount of bind.

Usually bind is just more force to move the required distance and if that's what you have the lighter weight you have would get the results you are seeing. It is definitely a possibility.
 

revhead347

Apparently my ex-husband made that mistake.
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#10
  • Sep 1, 2021
  • #10
KRUISR said:
Have you tried undoing one of the upper control arms to see if you are experiencing any suspension bind?
Click to expand...
This is not a real thing in most contexts, and certainly not in this one.

Before you get too wrapped around the wire, put the car on the ground, let it sit for awhile, and then report back.

Kurt
 

Mstng93SSP

You have a nice rear end there Dave.
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#11
  • Sep 2, 2021
  • #11
I see adjustable lower control arms there, just like I have with the bottom spring perch that you can adjust the height on by turning the bottom threaded portion in and out correct? I see it threaded nearly all the way OUT. It needs to be turned IN so the bottom spring perch goes up. I have my threaded portion nearly flush with the bottom on mine.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#12
  • Sep 2, 2021
  • #12
Screwing the coil spring base down like he has it should lower the car, correct ?
 

Mstng93SSP

You have a nice rear end there Dave.
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#13
  • Sep 2, 2021
  • #13
No, it raises it. Moving the perch up compresses the spring and lowers the car.
 

impropernick

Member
Jan 4, 2021
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Sep 2, 2021
#14
  • Sep 2, 2021
  • #14
I just tried that out, and it ended up moving my ride height up lol. I'm going to try and take one component out of the system at a time to see what's causing it. Hopefully I can come back with an answer in a day or two
 

Mstng93SSP

You have a nice rear end there Dave.
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#15
  • Sep 2, 2021
  • #15
Did you try it with any weight on the car? Or suspension hanging?
 

Mstng93SSP

You have a nice rear end there Dave.
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#16
  • Sep 2, 2021
  • #16
You guys may be right, I might have it backwards? I do have mine screwed all the way in though, and my car is slammed.
 

impropernick

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Jan 4, 2021
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Sep 2, 2021
#17
  • Sep 2, 2021
  • #17
The weight of the car is on the suspension, I left the differential jacked up, and off the stands. I do appreciate all the replies and people trying to help though!
 

OldManRiver

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Sep 2, 2021
#18
  • Sep 2, 2021
  • #18
One check to do would be to remove the rear springs and cycle the suspension with your jack through it's full range of travel observing smooth operation with no binding.

Side note: If those are SN95 rear shocks,as instructed by MM be sure to remove the factory rubber bump stops located on the frame rail above the axle,the SN95 shocks are equipped with internal bump stops.
 
Last edited: Sep 2, 2021

Mstng93SSP

You have a nice rear end there Dave.
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#19
  • Sep 2, 2021
  • #19
You are not going to get a true vision of the height until it is on the ground. All 4 tires on the ground. Jacking, on jack stands or whatever is just not the same as sitting on the tires. Put the car on the ground. Adjust the rear control arms either screw them in, or out (it can easily be done with the car on the ground) and see what is what.
 

impropernick

Member
Jan 4, 2021
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Sep 5, 2021
#20
  • Sep 5, 2021
  • #20
I put it on the ground and nothing changed, the only thing i noticed was that one side was actually higher than the other, so that led me to believe there was some binding. So I took the diff completely out and noticed that the upper left control arm was super tight and it didn't line up with the bushings on the axle housing. I took them out, re did the 3 piece bushings on both sides of the UCA's since it looked like I put them in slightly crooked, and re-measured/adjusted the adjustable upper control arms to correct length. Put it all back together and now I have a decent drop!
 

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