Sean O'Hara

what brand should i go for, or just OEM? I dont want fancy adjustable ****.

//<86TA>\\

iTrader: (14)

ACdelco's are a good factory replacement, bilstiens are also a very good shock, and are not adjustable, but cost more. do not use anything from gabriel or monroe, all trash

Sean O'Hara

thanks, any idea it how much it would cost to replace everything with bilsteins?

UNCLE TOM

iTrader: (1)

just a thought but , you may want to think about new strut mounts . after 20+ yrs. they get a little loose . you WILL need a new alignment . good luck .

Sean O'Hara

good call.

Ron U.S.M.C.

I have done some research and for my DD I decided to go with "KYB-GR 2" front struts and "KYB Gas A Just" shocks for the rear. There is a video at the bottom of each page/link that explains how they work.
= http://www.kyb.com/products/shocks/gr2.php
= http://www.kyb.com/products/shocks/gasajust.php
KYB GR-2 struts are around 38.00 ea. and KYB Gas-a-just shocks are around 34.00 ea.
There not in the same league as Bilstiens but are not intended to be .They are intended to be a much higher/better grade alternative to cheap Gabriel or Monroes.

Sean O'Hara

would it be necessary to change the springs?

Pablo

iTrader: (1)

No

sofakingdom

iTrader: (1)

It's not "necessary" to do ANYTHING AT ALL, really.

But you'd be wasting your time on trying to "renew" the car if you didn't change the springs.

Go ahead and change them. You won't believe the difference they make.

motenkjr

iTrader: (1)

What's the point to changing the springs? I thought I read somewhere that they don't wear out. Please correct me if I'm wrong because I'm trying to learn as well.

Pablo

iTrader: (1)

They don't really wear out. If you have a lot of corrosion on the spring or any mechanical damage then it's a good idea to change them. Outside of that, the spring rate does not change.

That said, a stiffer set of springs is a nice handling upgrade when carefully selected for your combination.

sofakingdom

iTrader: (1)

Springs "wear out", same as anything else.

Take a coat hanger and bend it back and forth about a million times. Come back and tell us what it's like afterwards.

Thaat's EXACTLY the life a spring lives. Granted, springs are made from metal alloyed specifically for its ability to deal with that, and are heat-treated and otherwise prepped accordingly; but ultimately, iron is iron. The principle remains the same.

Go change a pair out, and then come back and tell us what you experienced. (the OP that is) I'd suggest starting with the rears since they're SUPER CHEEEEEEEEEEEEEEEEEP (less than a tank of gas) and only take about 3 or 4 minutes to swap if you're slow like me. You're probably faster than me though so the actual swap-out will take less than half as long as just jacking the car up with a 2-pump NASCAR floor jack and letting it back down.

Pablo

iTrader: (1)

A spring is not undergoing plastic deformation like your coat hanger analogy. Plastic deformation is exceeding yield and immediately damages the metal.

Springs see elastic deformation, and while fatigue can eventually damage a metal under elastic deformation, this depends on the endurance limit in question. Under the endurance limit, a steel spring can practically live forever.

WilliamSilver

iTrader: (6)

I guess you have a point but you have to remember that these springs have been supporting the weight of the vehicle as well as compressing /decompressing for longer than i've been alive. Without a doubt they are probably sagging due to wear.



Op I would personally do the mounts as well as factory replacement springs or an aftermarket set. Think you'll be satisfied after that

1ADan

iTrader: (4)

forgive my limited knowledge on the subject, but with worn/blown shocks and struts, wouldn't that potentially put the springs in a situation which is out of their application specification? causing them to wear? since the shocks and struts are no longer dampening their travel, they are more free to extend and compress more than intended?

IROCU2

Dan seems to me that your thought process makes sense to me. Not trying to knock Pablo but this is the way I envision it too.

SCCAjunkie

A few things-

For dissertations on springs, see the other thread in this forum

I would, at a minimum, change bushings and struts/shocks.

KYBs are NOT a high-end alternative to anything. The GR2 is very similar to the Monroe-matic or Gabriel Red-ryder. The Gas-a-just is similar to the Sensa-trac, or whatever the equivalent Gabriel is. They are no better or worse. Be aware that most of the low-end shocks are high-pressure gas charged (a cheap way to prevent oil-foaming), and have significant "rate" and lift force associated with them. It's not uncommon to see higher ride height with new struts.

Bilstiens (I believe) and Koni's do not show this tendency. They are dampers, and do that job well.

While I have no experience with GR2s in this application, I can tell you that in my other experiences, the GR2 will NOT properly damp springs with higher rates than stock, and tend to cause a "floaty" and underdamped feeling.

My recommendation for stock replacement- replace bushings with stock rubber, install Sensa-tracs all the way around (about $140 for all 4 from Summit), and inspect the old springs for damage/corrosion. If any is observed, replace with Moog replacement springs. I'd also look closely at the strut mounts (and most likely replace them) and the isolators, as mentioned above.

Personally, I'd spend more on struts than I would on springs (unless the springs show damage), but then again, I race road courses, so car control and predictability is everything to me. I think nothing of dropping $1000 on struts/shocks/bushings/springs and $150 on a set of brake pads. My wife thinks about it alot though...

SCCAjunkie

No, iron is not iron. That is the flaw in your logic. How can a knife or file hold an edge, while I can bend a piece if rebar easily? Springs are meant to be cycled. If properly made and cared for, and used in the proper application, their life is well beyond that of any human.

Using that logic, I'd change springs last. You know the struts and shocks are bad, so replace them, and while they're out, do the cheap stuff (bushings and mounts) that would have to come off anyway to get to them. If you still don't get what you want, swap springs later.

If you might possibly do that, just be SURE to get shocks and struts that will handle spring rate beyond stock. If you are even considering a stiffer or lower spring than stock, than the KYB AGX is the entry point (because of valving and construction, not adjustability), and Bilsteins and Konis are where you should be.

InfernalVortex

iTrader: (4)

Im just going to say that I wouldn't bother changing the springs unless they're sagging so much you want to raise the car back to its original ride height. If they're soft then just cut a half coil and lower the car to bring the springrate back up. People spend big bucks on lowering springs that have tolerably soft spring rates so that they can get the sporty look without the awful ride quality.

You dont want adjustable shocks/struts, so Im going to assume you just want to drive around in the car, not go professionally racing. In that case dont bother with fancy pants expensive stuff unless you just want to know that you'll never have to replace them again. Just replace the shocks and struts with whatever you can afford.

IROZINCO

iTrader: (1)

i love my gr-2s. I have gas-adjust up front and gr2 in back. It DOES raise you up a bit (in Colorado, thats not a bad thing!) but it handles very well. No floaty feeling at all. I did change my springs, but that was because some ding-dork had lowered them with a welding torch (!) it was riding on the bump stops. Since you gotta take the springs out to replace the shocks anyway, i'd just do 'em. They aren't that expensive. If you are on a budget, and the springs don't look messed up, you could re-use them. Kinda your call.

Pablo

iTrader: (1)

If you think that's scary, there are commercial aircraft (perhaps one you've ridden in) who's wings have been flexing up and down longer than you've been alive too. The really horrifying part is that they are made of aluminum which has a much lower fatigue limit than steel.

Fortunately aeronautical engineers don't design aircraft based upon what they believe/feel/assume. Science involves facts, numbers, repeatability. If you can't produce any of these things you aren't even making educated guesses, you are just believing for the sake of belief.

Luckily, you have nearly the whole of human knowledge at your fingertips - the internet. This development is without precedent in the whole of human history. Not even 600 years ago books were rare because the printing press did not exist, and now you have the opportunity to do something those people couldn't; learn about any topic at any time.

So when people just choose to "believe" how a scientific process occurs, I am dumbfounded. This is 13th century thinking. Why don't you step into the 21st century and start reading about fatigue, creep, modulus of elasticity, stress/strain, plastic/elastic deformation, and so on? You would expend more physical energy having a bowel movement.

The information is literally seconds from your mind if you want to step beyond merely believing.

Pablo

iTrader: (1)

Anything is potentially possible. If we focused on just what was possible without regard to what is likely we could construct any number of fanciful scenarios that suit are preconceived notions.

That said, metal fatigue is a process that depends on both cycles and the amount of stress - these are two different things. So if you were to highly stress a spring, say take it into plastic deformation, you could quickly destroy it - the paperclip example. The other end would be subjecting it to stress just at it's endurance limit for 10 million cycles.

Worst case scenario, someone is driving around without shocks. Is the spring going to be subjected to plastic deformation? No. The car has bump stops before the coils can even bind. Can the spring reach temperatures where creep occurs? Tell me, do you think the spring will reach 450 degrees f? If so, for how long? Creep has a time component... its going to have to be 450 F for years before it has an effect. Likely? No.

Lets pretend that the steel does fatigue (it does not wear).. Spring rate increases as the number of active coils decrease, so if springs decreased in height, their effective spring rate would go up because of the reduction of active coils.

The point is, it's unlikely, and outside of corrosion, mechanical damage, or manufacturing defect, people that test springs in a device that accurately measures the rate do not see them change their rate.

Mortorq

But we still see drooping cars with sagging springs, so, aren't the spring's life over at that point from simple wear and use? In effect, they do wear out?

InfernalVortex

iTrader: (4)

https://www.thirdgen.org/forums/susp...ver-rated.html


Personally, Im not getting involved in taht argument, but I will say that with good shocks the sagging springs shouldn't affect anything negatively besides ride height. If you just dont like the way it looks, get new springs, otherwise it doesn't matter unless you're going racing. And even then it's highly debatable, hence the linked thread.

Steven6282

I don't really want to get involved in the argument either, but I would like someone to explain to me how a sagging / drooping spring is not worn out. If it had the same spring rate as before, then it shouldn't be capable of sagging / drooping as the spring rate would be holding up just as much as before.

Granted the rebound strength of it could be the same because it's compressed tighter, do something to make it compressed only as much as it's normal height of compression and I'd be willing to bet the spring rate will be lower. IMO if it's sagging / drooping, it is definitely showing signs of some kind of wear...

InfernalVortex

iTrader: (4)

I would read through this:

http://www.afcoracing.com/tech_pages/spring.shtml#rate

And just make up your own mind. I dont think it's worth changing sagging springs unless you're racing. Good struts will maintain ride quality.

KITT1983

iTrader: (3)

What is a good set of struts and shocks and a set of springs with stock ride height?

boyinkeywest

I just put new motor mounts in and new springs and new struts front my 88 camaro. "The spring are not that use to put in" to remove the motor mounts I had to springs. I took my new spring I put under the car and let the weight of car compressed it then took a chain with hook in center 3 loops. Took 2 inch smaller made user to install. i try to post pics

TheExaminer

Changing springs makes a huge, huge difference. I changed all of mine out in my 4th gen Camaro along with new s&s and I could not believe the difference. It literally drove like a brand new car. I plan to do the same thing with my thirdgen Firebird soon.

InfernalVortex

iTrader: (4)

I would attribute that change to the shocks and struts, although the 4th only has shocks.

Good luck getting the correct springs for your car. There were tons and tons of different springs GM made for these cars, and they were all computer selected for your suspension package, trim level, and vehicle weight.

TheExaminer

We had this same argument a few months back. 4th gens don't have struts? Ok. I've changed just shocks and struts on my 4th gen Camaro before, and in no way whatsoever did it make as much difference as changing springs as well as s/s. It wasn't even close. You can tell me all day that it didn't matter, but I'm the one driving the car. Thanks for the well wishes, but I'm going with 4th gen springs in the rear, the front I may leave alone--I haven't decided yet--but if I do change them I'm not looking to have a lot of trouble finding them, I'm not an idiot, and I'm also not planning to take it racing. Good grief, I drive this car 1-2 times a week and take it to shows occasionally.

InfernalVortex

iTrader: (4)

That explains my deja vu!

I have had different springs in my car before... several different springs. I dont understand what you mean by "make it feel like a new car", in my experience new shocks and struts made mine feel like a new car. Springs made a difference, but it wasnt a "this is better" and "This is worse" kind of difference. But I dont have an issue with you having an opinion on it if you've got a direct comparison of doing it both ways. That's pretty empirical. You clearly felt a difference, and if you've changed only shocks before (Assuming same brand, etc) and saw a difference, that is definitely useful real world info. We all have experience in different areas, but a lot of us dont even have our cars long enough to make a direct comparison like that.

I just point out the shock/strut thing because I think it when we're talking 3rd vs 4th gen parts it gets confusing trying to keep track of which is which. It just helps with clarity. IN the big picture it's completely irrelevant.

And it's my experience playing with springs and watching other people deal with moog replacement springs that make me leery of advocating new springs in these cars. 4th gens with their much softer springs might have a much more exaggerated change in effectiveness over time.

The front springs are just such a pain to get in and out of the car. I've figured out a useful way to do it, but the new moog springs tend to be too tall, and that makes it even more difficult to get them in the car. The spring compressors scare the crap out of me, so I do it a different way, and it's still a pain. Im all about saving someone the trouble of doing all that.

Moog makes MANY different replacement springs for our cars, and there's no direct cross reference for a GM spring to a moog spring. You cant convert a BZY to a Moog Spring A and a BZW to a Moog Spring B. At least, not in any way that i know. And the rear spring sare the same. there's several different rates that came stock even on the same trim levels, so it's kind of hard to say for sure if you're getting the right spring. that's why I say good luck, because there's tons of stories about guys, for example, switching to "IROC" Moog springs and the car just sits way too tall and they later had to trim down the coils. These cars just vary so much in weight that its very difficult to know what you should get. A Z28 may have BZZ front springs and NNM rear springs, or BZW fronts and NNN rears. There's a lot of stuff saying "Z28 gets spring rate X", but the fact is that even Z28s got multiple suspension packages so it's not even easy to figure that out. It just depends on a bunch of moving parts. But maybe there's a cross-reference chart Im not aware of?

This thread should help:

https://www.thirdgen.org/forums/susp...ring-rate.html

http://www.hotrodbuick.com/springs.html

You'll find it's kind of frustrating to figure out what you need. Especially since you cant find info out there even saying what spring rates all the GM springs were from our cars. I have no idea what a BZX front spring's rate is, and you almost have ot order the entire moog catalog and do your own cross referencing across a selection of all of the OE springs to really know for sure.

TheExaminer

My 4th gen was bottoming out a lot going up small inclines, like out of driveways onto the hyway etc. The struts and strut mounts were shot, so I decided to replace those. I forget what made me think to replace the front springs, I think it was something I saw online. They weren't super expensive, so I went ahead and did it. When it was done, it looked like something out of a cartoon because it raised the front about 1"-1.5" higher--returned it to its stock stance--but the rear springs had not been replaced, and the sag is what made the car look like something out of a cartoon with the front being elevated. I replaced them too then, and it leveled it out. Over time, I didnt notice how bad the sag had become til I swapped them out. I've had that car since 2000, so yeah, I know every nuance and squeak. I do agree that thirdgen stiffer springs sag LESS, but they do still sag. Honestly, my front end on my thirdgen doesn't look like its sagging a bit. The rear MIGHT be down 1/2"-3/4", but nothing like my Camaro was with old springs. That's why I say I might leave the front alone and change the rear. I've got 4th gen spring cushions I'm going to add too, that will help a little with the stance.

TheExaminer

4th gen a few months after spring swap....

InfernalVortex

iTrader: (4)

That Formula looks great man! I wouldnt touch the springs in it! I've always loved clean Formulas, though...

They say ideally the rear should .5 to 1 inch taller than the front. Anywhere in that range is acceptable.

TheExaminer

Thx. My biggest reason for switching to 4th gen in the rear was to get the variable spring rate to make it ride smoother under normal driving. I have the 4th gen cushions, may just go with that first and see what happens with a shock/strut change. Btw, do you recommend sway link changes too? If so, what's the correct color, or does it matter? Rockauto had some dark blue ones for a good price. The ones on the car don't look too bad, but I want to do everything within reason to get rid of the squeaks/rattles, and smooth the ride out. Going over rr tracks just about shakes me to death. So for now it's s&s and 4th gen cushions. Changing all bushings is on the list, and sfc's eventually. I think that might take care of most of my squeaks.......

87350gtanj

KYB's are great had them on my last 87 gta and they will be going on my new 87 gta too once I get some other things taken care of...

-=Z28=-

iTrader: (3)

the springs on a cars suspension are similar to a spring on a valve. . They DO wear out. They last 4 to 5 times longer than shocks. Usually when a spring is bad, the vehicle will "sag", the only way to really test them is to have a spring manufacture test them similar to how they test a valve spring. Personally I would start with struts and shocks. you can find struts that are custom valved to what your driving needs are. I got my custom valved struts threw TPIS. 135$ i think. and as posted above there are many shocks to choose from. I also have eibach pro springs and I tell you what...... it handles like a dream. As the cornering gets more aggressive, the suspension loads up and grips the road even better. I love how it handles. car and driver voted the 84 z28 the best handling car built in America, bar none.

-=Z28=-

iTrader: (3)

I got all my stuff threw tpis. it lowered it about a inch and a half. Eibach pro springs and tpis custom valved struts. they have shocks too. these guys are masters when it comes to camaros and vets. My car handles like a dream.

-=Z28=-

iTrader: (3)

This is copied from a company called Spring Works.

HOW are Coil springs inspected?
The most common method of coil spring inspection is checking the vehicle ride height. Measure! Don't rely on eyesight alone! This method will only catch the extreme cases of spring sag or leaning. In addition to checking ride height, look for these signs, which also indicate the coil spring requires attention:

Examine each spring for stress cracks, missing coils, or shiny spots between coils.

Damaged bushings, bump stops, or MacPherson Struts.

Front end of vehicle nose dives when braking or vehicle sway. Spongy ride.

Vehicle that commonly carry extra weight, resulting in unlevel condition most of the time (family transportation, work trucks, and sales fleets)


WHEN do coil springs need to be replaced?

There is no standard life expectancy of springs. In general, coil springs on heavier full-sized vehicles tend to last longer than those on smaller light weight applications. To determine when coil springs need to be replaced have the springs inspected and the vehicle ride height checked by a trained professional.

TheExaminer

Heres the link to my thread that shows official body panel gaps and trim heights for most of our cars if anyone is interested. I tried to load them into this thread, but for some reason it won't let me tonight. This would be what you'd use to measure spring health.

https://www.thirdgen.org/forums/body...anel-trim.html

Johngypsy

Well, guys I know I am late at this, but this is for the new readers out there, I own a 90 Iroc z, it already had the g2 struts ans rear shocks to it, which In all made my car lifted up by over 1 inch, so now my car looksike it's a mini 4-wheel drive, as I now see the inner fender wells, and seeing all the dirt and dabree I have here, so the g2 performs like notheing els, I mean she handles so well, and I corner beyond. ( after market sway bar & rear sway ) front 36.5 rear 24.2 so wth that said I wanted more, and to bring down the car a bit this time, so after the tons of reviews of the koni struts and ahocks, I finally got them ( THMOTORSPORTS ) at a bargin deal, under 550 for them all when they had the sale going, as far as springs, got the red 1 inch lowered ones, nothing serious like 2 or more, the koni's are said to be designed to be with any lowered springs which is better on the struts. I went a little crazy and got the rear sphoons welded in brackets on ebay for 59 dollars shipped, and found the sale of the rear adj control arms also by some manufactor with the wobble end, the car came with a box of the red or orange Polly bushings, which has not yet gone on the car, friends told me why stop there, so I found the sphoons transmission adj torque arm and the Trans bracket with the loop deal, found the sphoons weld in sub frame connectors on ebay brand new from a guy who bought them and sold the car the next week for 120 shipped, and found a deal on the inner sway bar for the suspension set up, plus so much more down to the steering box with the 2.5 turning circle, plus again much much more I have for the suspension, billet adj sleeves to, but not yet the mount for the strut, have a used tower brace with the 3 circles in the center to. But all not inatalled as of yet,
I wanted to see what this car would turn like with these all on, lol. I hope I get to see it before I leave this earth, a closet full of parts all new, I got these parts because of your feedback from thirdgens, from the guys who has this, it's your choose of parts that was chosen that made me do this up coming build, I will try and put up a pict if I can threw my phone for you guys to see,

Not only do I have these parts saved, but I've done every single job under the car from every suspension parts from napa, just so I don't have to do them again anytime soon,

So as far as the front struts are concerned. STAY AWAY FROM MONROE, and the other one listed by the member here, I got the first set, and the car bottomed out almost instantly! Literally wast of money. Took them off and almost threw them in the parts guys face as he gave me a good deal for 27.99 each. Front & rear was 19.99, so not worth it at all,

So I've read the entire post here as far as my few other parts I need to complete my suspension sys, I am going the A&g's ones. For the strut monts, again from your guys feedbacks,
You and all of you guys are extreemly honest and always speak and tell the truth for the real parts that we so need for the 3rd gens out here, as nkw these cars are not even in any more junk yards, as the rusted ones are now being restored, and org owners only crave what they had and wish they still had them,

Thanks guys for the feedback here,
John
Iroc z parts and supplies
Houston tx,
For all your factory 3rd parts needes.