oamhmad

iTrader: (1)

After about 100K miles or so I'm wondering if I need new springs on my 84 TA with original WS6 suspension package.

I've heard a lot of people say that at 27 years old the springs are worn and sagging and need to go, but is that really so?

My car has a stiff ride as can be expected from the WS6 package and body roll doesn't feel too bad. So if they're worn I can't imaging how horribly stiff and uncomfortable new springs will be.

Not to mention the ride height increase from new springs. So If I'm looking at this right, new springs will make the ride more uncomfortable and make the car look goofy. So what's the point of replacing them just because they're old if they're not broken, cracked and the handling is fine?

Maybe worn sagging springs aren't so bad after all?

Pablo

iTrader: (1)

You are asking the right questions.
People seem to equate sagging springs with decreasing spring rate, this is simply not the case. While the springs can and do eventually sag, the spring rate does not change (extreme examples excepted). This is basic metallurgy.

There are plenty of arguments to be made for changing springs but they principally center around handling. So if you are happy with the handling, there is no reason to waste your money on springs, and believe it or not, the stock ws6 springs have decent rates for handling anyway (you can easily increase them by cutting).

sofakingdom

iTrader: (1)

The srping rates ABSOLUTELY DO change. This is basic metallurgy.

The change in rate is THE VERY REASON WHY they sag in the first place. This is basic physics.

Take a coat hanger and bend it back and forth about a million times, and see if it's still as stiff as it started out being. A spring is no different in principle; while it might not lose its temper as much or as fast as the coat hanger wire, it works EXACTLY the same way. This is why for example, you see older cars whose shocks have been neglected, sagging worse than cars that have always had good ones; the bad shocks allow the spring to bend more times (from all the flopping up and down that the suspension is allowed to do), often by a factor of an order of magnitude, which wears them out just that much more.

Change your springs. The difference is ASTOUNDING. Start with the rears if you don't believe me: you can do them in a matter of minutes, and the cost is less than a tank of gas. Use Moog CC635 if you want a variable rate or 5665 if you want constant rate.

The stock WS6 springs in 84 had a pretty low rate; the fronts for example were around 350 lbs/in WHEN NEW if memory serves. By contrast, stock replacement IROC springs are in the 700 lbs/in range (5664 or 5662). I don't recall the stock rear rates off the top of my head, but the difference between NEW ones and replacement ones is somewhat similar; and after the car literally becoming almost an antique, you can be assured that they're NOWHERE NEAR the same rate that they started out life as.

SCCAjunkie

Sofa,

As much as I respect you (since I read and enjoy a LOT of your posts), I have to disagree on this one.

There are only really a few situations where a spring *should* change rate, and age and *proper* use are not really a part of that.

1. Causing the spring to deform outside of its elastic range. Perhaps this could happen in very isolated circumstances in a vehicle.

2. Exposure to enough heat to change the heat treatment of the metal. Not likely in the vehicle if the vehicle is still around That said, overworking a spring can create enough localized heat to change the properties of a particular part of the spring, leading to cracks or breakage. If you drive around long enough on bad shocks though, you can build up enough heat to cause internal changes to the metal.

3. Improperly made springs that were not heat treated correctly.

4. Physical damage to the spring (impact, gouging, etc.) that changes the shape of a particular part of the spring.

The situation to which you refer above (coat hanger) is not a good analog, because that metal has not been heat treated or alloyed to extend its elastic range. The coat hanger experiences work-hardening, and actually gets stiffer prior to breakage. If your point rang true, we'd all be looking for used springs and Eibach (and others) would be in trouble, since used springs would give us lower ride height (due to sagging), and higher rate (due to work-hardening).

In the end, springs do sag by changing their rest position slightly over time. This sag, however, is rarely accompanied my any change in rate. People might think they feel softer, when what they are typically feeling is worn shocks/struts, worn or sagging bushings, or hitting the stops because the springs that are still the same rate are fully compressing due to lower static ride height.

That said, the springs on thirdgens can experience some of the above situations, since they are often exposed to:

• other worn suspension components, pushing the spring beyond its design
• conditions outside the design parameters do to driving style
• damage from accidents
• localized damage from impacts or other issues (proper care not taken when installing, etc.)
• corrosion

Add this to the fact that the production parameters on these parts were NOT ideal (during the 80s "quality control black hole") and the underestimation used when designing the suspension, and you have huge chances for springs to sag, break, or possibly change rate under seemingly "normal" circumstances.

In the end, a properly designed and constructed spring, cared for properly, and used in the proper application, will NOT change rate. I think this is exactly what Pablo was getting at.

Pablo

iTrader: (1)

Thanks for the reply SCCA, and geez, talk about a lurker! Member since 01 with only 78 posts? You should contribute more often!

Greetings Sofa,
Always a pleasure to see you reply to my posts. You encourage me to brush up on whatever topic I have posted about. Thanks.

As SCCA touched on, there is a long answer to this question, and a short answer.

The short answer is what I provided. This is based upon the observations of people who test coil springs and have found that even well used they tend to not vary in spring rate very much. They also say that they sag is actually rather uncommon.

The long answer is more complicated. You could make a real science project out of this if you want. Your example of a paperclip is not a good one. With the paperclip you blow right past elastic and move into plastic deformation, a spring sees elastic deformation. Your paperclip gets easier to bend because you have immediately exceeded the yield stress of the material on both sides because of fully reversing fatigue, which a spring in a car does not see.

There's a lot to consider,
Fatigue: Do springs exceed their endurance limit? Steel that doesn't won't fail in fatigue and pretty much has infinite life. How often does a spring exceed it's endurance limit if ever?
Creep: Can a spring get hot enough for creep to occur? Creep is time dependent too, so how often does it get this hot?
Corrosion or mechanical damage: both lower the endurance limit, and also the cross sectional area of the spring

Then you have to consider that fatigue is micro cracks forming on the side where there is tensile stress, so that side is going to grow in length relative to the side seeing compressive stresses, the result is that if there is fatigue, the spring is going to shorten in stature. The modulus of elasticity of the metal itself does not change though. The only thing (well not the only thing) this affects when calculating a spring rate is the diameter of the coil wire which would be a tiny bit (like a microscopic amount) smaller, again, if this is happening at all.
The other thing this effects is if the spring does sag, there is a slightly reduced number of active coils when installed in the car. So while a microscopically smaller cross section would decrease the rate by it self, the reduction of active coils would increase the spring rate and possibly offset or outweigh this.
If it is happening, as I understand it, the stress causing it is likely not seen frequently. If it was, we would likely see coil springs completely failing on cars a lot more often

I would say a more likely explanation for sag if it exists is corrosion reducing wire diameter which incidentally also reduces the endurance limit. An endurance limit which we might still be very far away from.. And again, any sag is accompanied by a reduction in the number of active coils which increases the spring rate.

So I stand by my previous post stating that outside of extreme examples, like significant corrosion, mechanical damage, etc, spring rate is not really going to change. I base that upon empirical evidence of people testing them and not seeing any appreciable differences.

I welcome anyone with better understanding of this topic to amend anything I have stated if it's not accurate.

sofakingdom

iTrader: (1)

Pablo:

Go bend a coat hanger back and forth about a million times, and come back and tell us all HONESTLY (for a change) what you ACTUALLY saw about what ACTUALLY happened. NO candy-cotaing, no excuses, no "but but but but", just THE FACTS. Stick with REALITY and TRUTH. Tell us what REALLY TRULY ACTUALLY HONESTLY happened when you ran the experiment.

Did I mention, I have no need to lie, fabricate, make stuff up, or whatever else? I urge you to try the same.

Or, just try this radical idea:

Go out and BUY a set of NEW springs (yeah I know), and put them on your car, and THEN, tell us HONESTLY, TRUTHFULLY, and WITHOUT BIAS or PRECONCEPTION, what happened. That's all I ask; the willingness to perform the experiment, and the HONESTY to acknowledge the OBSERVED results.

Pablo

iTrader: (1)

Greetings Sofa, peace and happiness to you my friend.

Do you know the difference between plastic and elastic deformation? Or how spring rate is calculated?

What you suggest I do is not a scientific experiment. It will tell us nothing about springs, only about what the placebo effect is.

A simpler test is to take two springs of the same manufacture, size, and type, one of which has been cycled x amount of times with the same amount of stress seen in a car, and one that is new. Put them in a spring rate tester and compare results.

Fortunately, that's been done before.

Tonygxp

easy guys easy..... I have four stock replacement for my GTA springs coming in tomorrow. they will be installed probably thrusday evening and an alignment either Fri or Sat... i will post right here in this thread as well as my other suspension build thread. believe me, i am looking for a "better" ride and remember how it drove prior to all the suspension upgrades i have done. IDK what to expect from new springs, i had zero intentions of changing them but upon removing the old fronts they were both cracked/broken all the way through in the same spot almost to the exact location it was strange??? approximately 5" from the end of the bottom coil (following the coil around from the open end where it sat in the a-arm)

87350IROC

iTrader: (2)

Factory springs are not that stiff. The harsh ride comes from bad or worn out shocks and struts. You can go much higher than stock rate and still maintain a nice ride with quality shocks and struts. I would replace them well before I would consider replacement springs.

I didn't believe it myself until I installed a set of Koni's in the car. The ride now is pleasant even with much stiffer than stock springs.

micktroup2

On my previous car, 1991 V6 RS, I replaced the springs and had to cut 1 and 1/2 coils off the front and one off the back to get down to where the stock ones were. Did the original ones sag after 20 years- I don't know. The ride was far better, I know that. On my current car, 1991 Z28, I swapped the rears from the RS over and the height went UP. The rears, that were new in my first car and swapped over to the Z28, remember, are progressive wound, whereas the Z28s were constant...The fronts were replaced with new Moogs from Summit. The new ones were much thicker wire and SHORTER than the stockers! I still cut a coil off and the front fender height is right at 25 inches- this thing is pretty low! I did notice that on the earlier car AND this one, the rear is much quieter and the ride is generally tighter and 'newer' if you take my drift. But I also replaced the A arm bushings with urathane etc, so the suspension is all new. Also, don't discount those damn coil isolators- mine we're chewed to hell and I replaced them with heater hose as well...

sofakingdom

iTrader: (1)

Yeah valve spring mfrs (and users) do that all the time... and GUESS WHAT: the rate goes away. Just exactly as basic metals properties would lead one to suspect they would.

Yes I'm familiar with how spring rate is "calculated"... although that's a bit of an exaggeration... rate is lbs per inch; all you have to do is put some # of pounds on it, measure how long it is, put a few more on or take a few off and see how much it changes (since even a "constant rate" spring isn't quite exactly "constant", it helps to take the measurement at near the intended "at rest" load) and see how far it moves.

It really is amazing how much difference new springs make. ABSOLUTELY the biggest bang for the buck suspension mod, ESPECIALLY int he rear, where they're SO CHEEEEEEEEEEP and SO EEEEEEEEZIE to swap out. You should try it some time; except, make sure you use NEW ones, not old junkers. Try either Moog 5665 (const rate) or CC635 (car rate) on your car. You'll kick yourself in the butt for having driven it around for so long with old wore-out junk - that wasn't real good to begin with - making your life miserable. Night & day difference.

zzjakect

SofaKing,

I'm sold! If I can do this in minutes for less than the price of a tank of gas (although that is going throught the roof) I'll do it this weekend and post results. Big question is...........How do i do it? procedure or a thread???

jermdm

Here's my 2 cents. Springs set your ride height. They wont make you car ride smoother, softer, or stiffer. Thats what the shocks and struts do. Have to remember that shocks and strut pistons are suppose to be positoned in a certain spot inside the tube for maximum effectiveness. When you lower a car or have weak/sagging springs, that puts the pistons in a different spot which can make your car ride rougher than it suppose to. Lowering a car the wrong way or having weak/sagging springs changes the geometry of the suspension and steering componets which can lead to handling problems. Springs will wear over time and become weaker. I agree with sofakingdom. Metal can only be flexed back and forth so many times before it breaks or becomes weak. This goes for springs also. My iroc was all over the road when I drove it. The backend was sagging and the struts and one shock was bad. I replaced all the springs and shocks and struts and what a difference it made. The back sits higher, where is suppose to be and my handling issues are gone. Best money I spent in a long time.

SCCAjunkie

Not all shocks and struts are like this- in fact, most aren't. I can tell you for an absolute fact that Konis are not built that way. I would assume the Bilsteins are not either.

You guys are also missing a key point with this "weakening spring" theory. The more cycles at normal piece of steel goes through, the MORE BRITTLE it becomes. This leads to extreme stiffness and then breakage, not "softening" or any reduction in rate.

GreenCamaro13

Ok ima jump in on this CONVO. ok so my car has not had springs changed even ONCE or been serviced. it is a 1991 camaro rs v6.

Lately the springs have been squeeking, time to replace or just furbish them up? and how so? thnkyou all!

Pablo

iTrader: (1)

I'm amused, myself and another poster explain the science of why springs do not decrease in rate. I mention fatigue, endurance limit, creep, and then the factors that affect the rate of an installed spring; active coils, wire diameter. I point out that to accurately compare you would need the exact same springs on a spring rate checker, etc.

Another guy talks about paperclips and coat hangers and he has people convinced to run out and buy some cargo coils.

I guess this experience validates the effectiveness of the psuedo science advertising I see on tv, if nothing else.

SCCAjunkie

You can't "refurbish" springs, at least, not in a way that would be cost effective.

Luckily (or unlukily, depending on your view), your squeaking is most likely caused by other suspension parts that are worn or need lubrication. Start with the things that can be lubed and go from there. Believe it or not, I've actually seen a tie rod end cause a squeak over bumps, and proper lubing took care of it. Proper maintenance lubrication kept it from coming back.

sofakingdom

iTrader: (1)

A process of failure that affects aluminum, but NOT steel - NOT applicable here

Don't think we're anywhere close to that here... we're just driving around on the street, most of us, not going out and stressing the parts to the very edge of instantaneous failure

Not particularly applicable to a piece of steel unless it's like red-hot... more a factor when dealing with plastic and rubber and such as that, even glass although it only "creeps" over periods of centuries

Which sounds wonderful, except that THERE AREN'T ANY: the spring HAS whatever rate is HAS, at whatever the installed height it ends up at


I haven't seen anything that vaguely dimly RESEMBLES "science" posted here telling why springs don't wear out. I've seen some "big sport-car words" thrown around, I've seen a bunch of stuff that is COMPLETELY unrelated to the topic at hand (e.g. "creep"), but no "science". Still haven't seen anybody go out and get a piece of steel (coat hanger) and subject it to the life of a spring (bend it back and forth) and measure the effect that has on the stiffness. I've been attacked for making a simple analogy ... well DUH, that's what an analogy IS SUPPOSED TO BE; cut through the clutter and get straight to the SIMPLE principle at hand, as opposed to obfuscating and confusing the reader with a bunch of "sports car" talk. In fact, it wouldn't surprise me in the slightest, if the person objecting to the idea that springs wear out and need replacement eventually, has NEVER IN HIS LIFE ever actually gone out and BOUGHT a set of springs, NOT EVEN ONCE, and ACTUALLY PUT THEM IN HIS CAR; and therefore HAS NOT THE VAGUEST CLUE what ACTUALLY TRULY REALLY HAPPENS when that is done. See this toipc here http://en.wikipedia.org/wiki/Cognitive_dissonance and its related reading, for what is going on here.

Where I come from, "spring rate" is the # of lbs corresponding to the distance that the spring deflects. Now I'll grant you I prefer to make things SIMPLE in my explanations instead of inventing stupid crap and throwing around random "big words" to try to impress the impressionable, which no doubt makes me look even stupider than I reallyam; but if a chnage in "rate" isn't what makes a car "sag" on its springs, then WHAT IS? RATE equals POUNDS divided by INCHES. Nothing more, nothing less. If INCHES changes, but RATE stays the same, then THE ONLY other thing that can account for the change in INCHES, is POUNDS. Are you trying to say that the reason old cars sag is because they're getting heavier? Or perhaps because the Earth's gravity is steadily increasing? Please enlighten us on how this works.

If springs don't wear out, then I suggest we should all quit buying valve springs, and just go get used stock ones at the junkyard. Now Pablo, we've known each other for a long time, and I know well that you refuse to take anything but ... shall we say, an "economically sensitive" approach ... to your projects, and I respect your emphasis on getting the most possible whatever for the least amount of $$$, and that's all well and good; but I think EVEN YOU would have trouble with THAT.


Anyway, to put this ridiculous fantasy of "springs not wearing out" behind us: zz, to replace them, you jack the car up with a floor jack under the pumpkin high enough that the rear wheels are several inches off the ground (with wheels chocked and all other safety procedures in effect, before somebody comes on here and tries yet another foolish meaningless way to discredit me by attacking the directions I'm giving as some kind of "unsafe" whatever); support the chassis at the lower control arm mounting points; let the rear down almost as far as it will go, like let it all the way down until it hangs, then jack it back up an inch or so to take the force off of the shocks; unbolt the bottom of the shocks from the rear end; unbolt the little brass block thing that the brake lines go to, from the pumpkin, so that when it hangs down farther it doesn't damage the rubber brake hose; then SLOWLY let the rear down as far as it can go. At that point the springs will FALL out. Set the new sproings in place, and reverse the procedure. You have the choice of leaving out the rubber insulators, adding thicker ones, replacing or augmenting them with heater hose wrapped around the bottom and/or top coils, etc., to "tune" them a little bit for ride height and road noise, to your taste.

As you can see, the shocks are already halfway out at that point, as well; makes sense to swap them out at the same time. Their remaining hardware is under the carpet behind the back seat: remove the seat back (2 nuts or 4 nuts, depending onwhich type of back seat you have); the seat bottoms (2 bolts), peel back the carpet from the seat area rearwards; lift out the 2 little foam blocks; you'll figure it out from there.

SCCA's "lube" suggestion is excellent. Many of the parts of the car are supposed to be greased periodically, particularly the ball joints and the steering parts that he spoke of. ALWAYS make sure that is kept up with, just like changing your oil. YOu can also spray silicone lube on the rubber parts to isolate any of those that squeeeek, as well; although some people recommend not doing that at least on a regular basis, it helps for troubleshooting.

redneckjoe

the valvespring analogy explains it pretty well. i recently called a cylinder head manufacturer about some heads i have. he noticed they were about 6 years old. said he recommended i change the valvesprings cause they wear out.

87350IROC

iTrader: (2)

That is BS. The springs and shocks work together to determine ride quality. A stiffer spring is absolutely.... well stiffer. If you were correct then an infinitely stiff spring (a solid rod) would ride just as well as a normal spring.

Pablo

iTrader: (1)

Sofa, you are really starting to make a fool of yourself, and I am sad for you. Fatigue affects all metals. I suggest you brush up on this topic http://www.epi-eng.com/mechanical_en..._in_metals.htm
Pay attention when the article addresses endurance limits, and what happens at the surface of the metal.

When you bring up spring rate, you are confusing two things, the modulus of elasticity of the metal, and the actual spring rate while installed. These are two different things, while modulus of elasticity does not change, when installed in a car, the number of active coils in addition to the elastic modulus, and wire diameter, is how you calculate spring rate.

Please, I urge you to not take my word for it, read here (might want to clean your feet first, one of them is going to end up in your mouth): http://www.engineersedge.com/spring_comp_calc_k.htm

A spring is more or less a bar wound into a circle, think of a shorter bar and a longer bar of the same diameter and same material. Which is the harder bar to strain (that means flex)? Obviously the shorter bar.
If a given spring were to sag because of a loss of rate, it would reduce the number of active coils, essentially shortening the bar. Why? Because the amount of coil touching each spring pocket would increase. Go ahead and play with the math in that link I posted and see what happens when you reduce the number of active coils.

A valve spring is not an analog to a suspension coil spring. Why? Because a valve spring does not change it's installed height. Not without catastrophic consequences anyway. The difference in installed height from free standing height on a valve spring is great enough that it is always going to be exert pressure upward on the retainer. Unlike a suspension coil spring where the installed height will change, and thus reduce the number of active coils.

Another factor that makes a valve spring different is that they are in a much harsher environment than your suspension spring. Subjected to heat and cyclic loading that your suspension would never see. When was the last time your suspension went from fully bottomed out to full extension 3000 times in one minute while being bathed with 200+ degF oil? The fact that valvesprings used for their proper application last so long (compare the number of cycles to what your suspension coil spring is seeing) should maybe tell you something.

Lastly, you made me LOL when you suggested that I have never changed coil springs. Suffice to say I have changed a few springs in my day

DeltaElite121

"Moog 5665 (const rate) or CC635 (car rate)"

Sofa, what is the difference between constant rare and car rate? Is car rate implying that the rate changes when it's installed?


And to contribute, it's not logical to assume that springs don't wear out.. at least based upon observation (if that's what is being implied) If that were the case, then we'd never need to replace anything spring related unless it was installed and/or used incorrectly. We deal with springs all the time at my work so I'll see if I can find a good example of the two. They may even LOOK just fine, but they don't react properly when compressed. I aways wondered the same thing, but experience has led me to the idea that springs should be looked at as a "degrading part" and replaced when necessary.. otherwise some things just STOP working properly because the springs (usually a critical component) aren't doing what they were intended to do consistantly.

Pablo

iTrader: (1)

No one ever said that springs can't "wear out". Anything can "wear out" when used outside of the range that it won't "wear out". Simple enough? Steel has a line where it more or less goes from where it can "wear out" to where it won't "wear out".

Please, I urge you to click on the link at the epi page I posted. That line is called "endurance limit". Above that, you are talking about two different factors that will tell you how long it will last, stress and time. The lower the stress, the longer the time it takes, the higher the stress, the shorter.

DeltaElite121

so just for the sake of curiousity, can you think of a proper way we can design a formula given a certain type of spring rate? I ask this because I have actually gone with a much lighter spring rate up front for my car. I'm curious to see if we can make an "averaged" formula to depict when it would need replacement based on AVERAGE driving conditions at "x" amount of weight. It's a very involved question, but I think it could be answered if we approached it properly.

I'll take a look at the link.

SCCAjunkie

Delta- unfortunately, there's no real formula, because there are too many factors. You'd need to address things like the number of cycles beyond the design limit, how far over the limit, temperatures, corrosion, and damage, to name a few. It also all goes out the window if the spring wasn't made perfectly. We can "shot in the dark" a few things, but not if you want any amount of reliability.

Sofa- I'm not criticizing the fact that you used an analogy- as I said, I often enjoy your posts for what they are- real explanations in real terms. My issue is when the situation is so different that the analogy falls apart.

After looking for a while- I finally found the site I was looking for:
http://www.afcoracing.com/tech_pages/spring.shtml
It's a very good explanation in real terms of the things I've been trying to say. It also discusses the situation you might encounter where rate might change (in an upward direction!) and explains the occurance of "sag". Keep in mind that this is coming from a company that makes money by selling springs, so if there were some reason to replace them as "normal maintenance," I would think they'd have mentioned it.

Sofa- I do hope the "fancy sports car words" comment wasn't directed at me. If it was, please let me know. I am not a person to try to dazzle people with big words- I only use them when I feel there's no better alternative. I spend my days teaching Physical Science in middle school, so my philosophy is:
It doesn't matter how much you know and understand. If you can't make it make sense to your audience, it's a waste of everyone's time- yours and theirs.

If you all will excuse me now, I'm off to instruct at the SCCA Racing School at Summit Point (WV) this weekend. Hopefully springs won't be a huge topic of discussion...

Oh, and Delta- I think "car rate" is a typo- they could've been going for "var. rate" as the CCs are variable rate springs (and the C key is right next to the V key...). I could very well be completely wrong on that though.

sofakingdom

iTrader: (1)

That would actually be "var" rate, as in "variable"... sorry for the typo.

They make those by varying the spacing between the windings. The "rate" of a spring is determined by the stiffness of the wire (the part that goes away after bending a million times), the OD of the wire, the OD of the coils, and the spacing between th ecoils. A variable rate spring has part of the spring with a lower rate, which as it compresses, reaches a point where its stiffness goes up, forcing other stiffer parts to begin compressing as well. It's how you make a spring that gives a reasonable "street" ride, but keeps the car off the bump stops when people are in the back seat or whatever.

SCCA, I couldn't have said that better myself... as a math & physics major my first trip through college, and now working through grad school (business) by teaching statistics, I've found that's a KEY difference between people who can teach and those who can't. Iv'e know LOTS of people who were REALLY GOOD at whatever they did, but were utter failures as teachers; and others who fumbled with their subject matter but sparked interest and learning in their students. 2 very different skill sets sometimes!! And no, I wasn't directing my comments toward you.

This particular board, more than any other on this site, seems to generate this kind of arguments. Invariably it's somebody who is, or thinks they are or wishes they were, some kind of a "racer" other than drag racing, DETERMINED to tell all the drag racers and daily-drivers how stupid they are and how little they "know" about this that or the other. Gets REAL tiresome. Also most of it has NO APPLICATION WHATSOEVER to the interests of the majority of this whole site's users: making their car less of a old wore-out broken-down falling-apart bone-rattling shaking sqweeeeeeking POS to drive. A VERY DIFFERENT pursuit from building the ultimate "handling" track machine. My advice tends to be more toward fixing wore-out stuff and making it like new again than on shaving a tenth off of a lap around cones or the like.

oamhmad

iTrader: (1)

I have new shocks on all 4 corners and the ride is still stiff. Granted I used the absolute cheapest shocks I could find from Autozone, Gabriel I think. They still made a huge difference over the old shocks. There was less bounce, roll and better grip.

I'm doing rear lower control arms this weekend and I wouldn't mind doing the rear springs just to see what happens. The only thing holding me back is the ride height. Right now it's 28 3/8" from the ground to the fenders in the rear and 28" in the front.

I really don't know which springs to get so the height won't increase. People have reported ride height increases with the springs listed previously in this thread.

sofakingdom

iTrader: (1)

Right: the ride height usually "increases", because the factory springs are virtually always so wore out that the car is already an inch or more below where it was when new, due to the effect of having been bent back and forth a million times like the coat hanger wire in th eexperiment. People even buy "lowering" springs, and discover that they RAISE the car instead of LOWER it.

Go here to see what these cars looked like when NEW. Remember that whenever terms about ride height like "stock", "lowering", etc. get tossed around, whether the people using them realize it or not, THIS is what they're ACTUALLY talking about. https://www.thirdgen.org/forums/hist...od-1986-a.html

Aaron91RS

iTrader: (2)

My car sat higher on the driver side. I pulled the stock springs out and the car this weekend.
Passenger spring is shorter(more compressed) then the drivers one.
That's just from the torque of the engine pushing harder on that side after 21 years.
So yeah they wear out, and not even evenly in my case.

Guest

How difficult is it to replace the springs(removing the old, installing the new) and how much of ride difference will I see. I don't know jack about suspension but am growing tired of my twenty year old suspension creaking and popping.

itsMikey

pretty amusing stuff..

Pablo knows what hes talking about..

87350IROC

iTrader: (2)

Springs don't creak and pop. New springs will not solve your problem.

itsMikey

bushings and shocks/struts as well as SFC's should handle it after springs

SCCAjunkie

Just to clarify-

I'm not saying springs don't get to the point that they might need replacement- I'm just saying they don't undergo a significant change in rate as they age. And if they do change rate, it would tend to go up...

Taking a "set" is a whole different story, and a significant difference like you saw Aaron is definitely a sign that replacement is needed.

And FYI- on my old 90 Formula, it sat low on the driver's side, and it wound up being a shifted subframe. All indications pointed to sagging springs- super-compressed, hollowed-out driver seat from Fat-Boy PO, all kinds of wear on the driver area of the car, leaky LF strut, etc. Hell, even the freakin swaybar had taken a set with a twist. Never could get that car to square up. I bet it even sets crooked on the rack at the junkyard...

oamhmad

iTrader: (1)

how did the sub frame shift? collision? and how did you pin point the cause?

oamhmad

iTrader: (1)

So for any one who is curious, I got my Moog 5665 rear springs today. They are about half and inch longer than the stock springs. The old springs were rusty but still intact after about 100K miles.

Pushing down on the old springs with all my weight, they didn't feel much different than the new ones.

I'm going to finish putting the rear end together, take the car for a drive and let you guys know if changing springs really is over rated.

Reid Fleming

iTrader: (2)

Odd. Mine were the exact opposite. Driver's side were way lower than the passenger side. I equate this to me being the only person in the car 99% of the time (230 lbs of me on the driver's side)

As far as the rate never changes, I wonder about that. Because if it were forever the factory rate, in theory the springs should never sag. After all, the cars don't suddenly get heavier as the years go by.

As for the original poster, I would say yes, do new springs and struts/shocks. My car has half the mileage and is 5 years newer than yours and it still had over a inch of sag in the rear and nearly 2 inches up front.

Pablo

iTrader: (1)

Sag happens because the spring gets shorter, not because it is more easily compressed.

SCCAjunkie

Sorry i had missed this.

We confirmed my fears via measurement on a frame fixture. The car was waiting for a 5sp conversion, then other projects and 2 daughters distracted me. Plan was to straighten things after the swap was done, but never made it that far. The guy who bought it stole it from me for the parts, and the chassis is in a crushed up cube somewhere.

Cool thing is, that guy just let me steal a nice 84 Z28 from him...

oamhmad

iTrader: (1)

New rear springs are in and the car rides much better! The rear end feels more planted and the car feels more solid through turns. Ride seems to be both stiffer and more comfortable at the same time, if that is possible. There is less creaking and groaning. Ride height increased just a little less then a 1/4" on both sides.

I also replaced the panhard bar and rear sway bar links so I'm not sure how that affected things.

sofakingdom

iTrader: (1)

Well I'm certainly not surprised to hear that... It's amazing how much of an improvement restoring the spring rate from wore-out to a proper value can make. Glad you like the results.

Atilla the Fun

I'm late to the party, but I have an '84 WS6 still on it's original springs, for now. Under the hood I have, for now, a tall-deck 427 from a medium truck. This is the heaviest engine you can bolt in. I also have a 700R-4 bolted up. Is the nose sitting low? Not at all. My rear springs are sagged, and I don't know why. My car has around 220,000 miles on it, admittedly, but has just been sitting for years. It hasn't been driven under it's own power on over 15 years now, and in all that time, there's never been anything heavy in the back seat or the trunk area. I'm replacing my springs, but mostly because my hitches are adding weight, and my cage will add more.

twigger

I could be wrong but replacing worn out bushings on your anti roll bar probably has a lot to do with your rear end being planted better and your improvement in cornering.

87350IROC

iTrader: (2)

Agreed it was almost certainly the other stuff that fixed the car, not the springs.