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Old 01-26-2020, 07:09 PM
pont3 pont3 is offline
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Default Question about springs

What, exactly, makes them need replacement? Is it the sagging, or is it the way they respond to movement? Do the springs lose their rate which causes them to bounce/rebound more/less? Do old springs affect shock absorber function? Basically, what I am asking, is what should one expect by replacing the old springs? The reason I'm asking is that I have replaced springs in the past and the only difference I noticed is that the front, or rear, of the car sits higher than the factory specs.

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Old 01-26-2020, 07:24 PM
694.1 694.1 is offline
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A broken spring should not need explaining but springs do sag with age. I was told that this does not effect spring rate but this seems a little counter intuitive...But maybe an expert will check in.
Two other reasons are the need to increase load capacity or to change spring rate (such as address handling characteristics).
Leafs & coils definitely can sag but when it comes to torsion bars -that is unknown territory for me.
I can tell you that nothing rides as crappy as a sagging leaf spring!

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Old 01-26-2020, 08:23 PM
pont3 pont3 is offline
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That's why I'm also hoping the "experts" would chime in, because my '72 still has it's original front springs, and I don't see any sagging. But what I HAVE noticed is that regardless what shocks I put on it, the car still seems to bounce too many times when encountering bumps and dips. I am going to change the front springs, but I was more interested in understanding the nuances of the springs themselves. Perhaps my aging mind has been driving too many newer vehicles, plus, my '71 with springs that were replaced over twenty years ago, don't seem to have the same problem.

So, I understand that things wear out, and I guess my real question is, is it the shocks or the springs? Or, does aging springs develop more "springiness and bounce" than less experienced springs? Seems to me that as springs age, they lose rigidity and become more springy, rather than controlled, but I can't seem to understand why.

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Old 01-27-2020, 06:45 PM
389 389 is offline
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Springs never wear out they just sag a little. No reason toe change them.. By the way Mark at SC&C has a new spring set for gm A bodys that's right on the mark.. He did a lot of extensive work on them.. They are 1" lower then stock from the fatory. Todays factory springs are way too high and are anything but factory. Marks are..

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Old 01-27-2020, 07:29 PM
pont3 pont3 is offline
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Quote:
Originally Posted by 389 View Post
Springs never wear out they just sag a little. No reason toe change them.. By the way Mark at SC&C has a new spring set for gm A bodys that's right on the mark.. He did a lot of extensive work on them.. They are 1" lower then stock from the fatory. Todays factory springs are way too high and are anything but factory. Marks are..
Are they "correct" right down to the flat upper coil? Tell me more!

Really, all I'm seeking is probably a technical explanation of why my car seems to continually bounce with oe type shocks that are brand new.

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Old 01-27-2020, 07:30 PM
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Unless somehow they fatigue (as in cracked), rusted, or lost more height then you prefer (or you want stiffer), no need to change them. Rate stays the same, just the resting height changes over time. Sometimes for the better.

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Old 01-27-2020, 07:42 PM
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Originally Posted by pont3 View Post
Are they "correct" right down to the flat upper coil? Tell me more!

Really, all I'm seeking is probably a technical explanation of why my car seems to continually bounce with oe type shocks that are brand new.

That's usually a shock issue. So, all I can think of is maybe the springs are not the correct rate for the vehicle (maybe someone used Chevy small block springs or 6 cylinder springs) which is overloading the shocks, or the brand shocks themselves are defective right out of the box (occasionally with aftermarket parts that happens).

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Old 01-27-2020, 08:12 PM
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Quote:
Originally Posted by pont3 View Post
That's why I'm also hoping the "experts" would chime in, because my '72 still has it's original front springs, and I don't see any sagging. But what I HAVE noticed is that regardless what shocks I put on it, the car still seems to bounce too many times when encountering bumps and dips. I am going to change the front springs, but I was more interested in understanding the nuances of the springs themselves. Perhaps my aging mind has been driving too many newer vehicles, plus, my '71 with springs that were replaced over twenty years ago, don't seem to have the same problem.

So, I understand that things wear out, and I guess my real question is, is it the shocks or the springs? Or, does aging springs develop more "springiness and bounce" than less experienced springs? Seems to me that as springs age, they lose rigidity and become more springy, rather than controlled, but I can't seem to understand why.
If you're putting factory replacement style shocks in the car, or even worse "performance" factory replacement shocks, this is somewhat to be expected.

The factory shocks were under-valved to being with which gives especially the bigger cars that floaty ride that a lot of people actually like. The result however is what's occurring is that the shock just isn't doing a very good job of dampening the suspension movement.

With old school style "performance" shocks that are marketed for these cars, they are geared towards straight line performance. As a result they tend to offer a bit more compression damping, but in a lot of cases, less rebound damping. This is where that bounce cycle is coming from.

Try instead a set of Koni Red's that have a digressive curve and offer better rebound damping. They are adjustable so you can dial in the amount of compression damping that is suitable for your driving style and desires. Likewise you can try a Bilstein B6 if you like their product line better than Koni.

Both of those would run you a bit more than $100.00 per shock. Quite a bit more expensive than the monroe or gabrielle that you can pickup for around $100.00 for all 4, but then, there's a reason for that.

Then you can get into shocks like the modern QA1, Alden American, Viking and Verishock offerings. These are large tube shocks that typically feature more rebound damping than compression. This gives you a ride associated with lower levels of compression damping and improves handling and body movement by actively damping against upward accelerations. You get a feel more like driving a modern performance/luxury car. You'll pay around $250.00 per shock for these and installation of the fronts will require the lower control arm to be separated from the spindle as the shock is too large to fit into the maintenance hole in the lower control arm. They mount on top of the arm as a result.

IMHO it was absolutely worth it to go the above route, however it does represent a lot of extra cost and more labor for install. As a result, that Koni Classic is a great middle of the road shock that doesn't get outrageously pricey and installs the same as the factory type shocks.

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