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Discussion Starter #1
So this is a thread I have been intending to start since the crash. It will be regarding my research on moog springs and what I ended up using. There are other brands of springs that are essentially equivalent and I will try to provide cross references. The goal is to provide good, cheaper alternatives to the sets of springs offered. Anyone with information is welcome to contribute.
 

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Discussion Starter #2
So in the rear I ended up using Moog 6381, and in the front I used 5044 with a coil and a half cut off (I think). I will verify this when I get a chance and provide specs and whatnot. It may take a little bit of time to get out all the information I wanted to provide since I am extremely busy right now but I just wanted to start this thread already.
 

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Sounds like a good plan to me. I'll be following the thread. I would be interested in measurements taken on a level surface from ground to wheel well.

Also, I'd REALLY like to know the measurement of the rear specifically when you throw a few hundred pounds in it.

I never installed air bags on my Hotchkis lowered car, and would like to see how other spring makes & models handle loads in the trunk.
 

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Discussion Starter #5
This is how my car sits with Moog 5534 minus 1 coil installed in front and Moog 6381 installed in rear.



 

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Discussion Starter #7
So the problem with considering the listed installed height is that it is not exactly relevant for our cars as it is with some other test weight...I have better estimates for the actual installed heights but I have yet to actually measure to see how close I am. 1 coil on this spring I thinnk was more like an inch and a half. I will do the calculation later and let you know.
 

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Discussion Starter #8
One of the original purposes of this thread was to post some suitable replacements for stock SS springs. Stock Impala SS front spring rate is 440. According to my estimates and calculations (and comparing to some measured data):

Moog 584 would ride just over 1/8" higher with a spring rate of 457
Moog 586 would ride about 1/32" lower with a spring rate of 433
Moog 5534 would ride just over 1/16" higher with a spring rate of 500
 

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Let me ask you this question, which of the following would seat highest? I think it's either 5552 or 5534?


_____________ Install Height / Load / Spring Rate / Free height
586:
Square Tangential 4.080 0.718 10.00 2705 433 16.06

584:

Square Tangential 4.080 0.718 10.00 2800 457 16.13

5534:

Square Tangential 4.080 0.750 11.00 2552 500 15.87

5552:

Square Tangential 4.030 .765 10.50 3025 543 16.19
 

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Discussion Starter #10 (Edited)
I answered this in the other thread, but the reason is that the installed height is not for your car but under the load rate spec'd. The ride height is determined solely by the free height (NOT the installed height listed) and rate. You should not even be considering installed height. 5552 would result in the highest ride height as they have both the greatest free height and rate.
 

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Could it be that you have to consider all 3 parameters together, to figure out where it will seat - installed height, rate in lbs, and free height?

Anyway, I think I will go with Moog 5552, as on paper it looks real similar to Moog 8000, (except the rate is about 100lbs higher, which is good). It might even seat a little higher, which cannot be bad.

Moog 8000 is the recommended replacement for stock wagon springs, according to rockauto anyway.

If the free height is the key value, then looking at your setup, with 1 coil cut, 15.87" - 1.5" = 14.37"

Meaning if I go with Moog 5552, which has a free height of 16.19", I will gain about 2" over your setup, which should put me right where I want to be. I want a 3" clearance between the tire and the fender lip to accommodate 255/60/17 which are a little bigger than stock SS tires (But the same height as 235/75/15" tires)

If I find another Moog spring with a 17" free height and around 500 lbs rate, that should be even better but it appears that 5552 should work.

FWIW, the "heavy duty" or 9C1 replacement springs you can get at autozone and the part # is FCS5030S. They do seat obviously higher than SS springs.
 

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Discussion Starter #12 (Edited)
Nope, definitely not. As specified, "installed height" is at the given "load rate". Notice how all of these springs have a different load rate? Well, the load rate of a given car is essentially constant (neglecting the seesaw effect as the front or rear is raised or lowered since it is negligible). So again, for a given car ride height is determined by the "free height" and "rate" of the spring.
It is a bit more complicated to calculate effect of cutting off a coil than what you have. When you cut coils, the rate increases and the free height decreases.
In a sedan, 5552 would result in approximately 0.5" higher ride height than stock SS. In a wagon, it should be more; I am not sure quite how much though.
 

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Discussion Starter #14
Interesting about the 7268. Does anyone have a set that is not cut installed? What is the trim height (highest point of wheelwell arch
Again, please remove the raw data as it is unnecessary to this thread. The point of this thread is for it to be easy to read through my conclusions which were reached after lots of research.
 

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Discussion Starter #17
i love how the car rides. i do, however, also have airlift bags installed; usually only run at minimal psi.
 

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I installed Moog 6446 in the front of my wagon last year, with approx 1.5 coils cut, and they are really nice!

Wish I could find a good match for the rear... I think my left rear spring is broken, causing a vibration between 50 - 65 mph...
 
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