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lowered spring replacement? coilovers? bump stop fix?..... by ltlgt88
Started on: 10-12-2012 02:01 AM
Replies: 18 (1755 views)
Last post by: fieroguru on 09-08-2013 08:08 AM
ltlgt88
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Report this Post10-12-2012 02:01 AM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
My car is already lowered 1inch with the FS lowering springs... How ever i believe one is starting to fail and i am getting a lean to the driver side. ( about 1.5 inch in rear (side to side) and ,5 up front (side to side))

it is an 88 GT with adjustable red koni's, 235/45/17 in rear 225/45/17 front

I have been doing some research and thinking about going with the West Coast Fiero rear coil-over kit (1984 - 1988)..
I do mostly City/Hwy driving with the car but sometimes want the performance when needed.
Should i go with this kit or just the FS lowering springs again?
Would it be better to have the adjustable so if i am doing a lot of Highway driving i could raise the car back up and would it give me a better ride?

I was also looking at the site and saw something about raising the Bump Stop by flipping the Bump Stop Plate, and grinding some away on it?
Has anyone done this Bump Stop Adjustment, and if so can you let me know a little more about it?
Should i take apart the front and do that adjustment too?
I don't think it was done originally when the car was lowered and wondering what type of difference it might make in ride quality?

I am only planning on doing the rear this time around...seems that is where all my lean is....is this ok?

Any info you have would be great...plan on taking this on as a winter project when the car isn't going anywhere anyway?
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Report this Post10-12-2012 02:20 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
[EDIT] Somehow I missed that the OP's Fiero was an '88. My front suspension info only applies to '84-'87.

 
quote
Originally posted by ltlgt88:

Should i take apart the front and do that adjustment too?
I don't think it was done originally when the car was lowered and wondering what type of difference it might make in ride quality?


I lowered my autocross '84 Fiero by cutting the springs. Without going into the pros and cons of using cut springs , I can say without a doubt that the front bump stops absolutely need to be shortened. I'm not referring to the rubber bumpers, I'm referring to the metal cones under the front springs. If this isn't done, you're basically sitting on the front bump stops all the time. The ideal width of the "ring" of metal to take out of there is 3/4". The bottom of the metal cone (along with the rubber bumper) is welded back on (to prevent the front shocks from bottoming out).

My lowered rear suspension doesn't even come close to bottoming out with the strut bushing plate mounted in the usual manner.

All springs had two coils removed and I have Monroe Sensa-Trac struts/shocks installed.

 
quote
Originally posted by ltlgt88:

My car is already lowered 1inch with the FS lowering springs... How ever i believe one is starting to fail and i am getting a lean to the driver side. (about 1.5 inch in rear (side to side) and .5 up front (side to side))?


Are you sure one of the rear springs has actually "failed" and hasn't simply altered it's position within its strut? My shortened rear springs will do this if I raise both rear tires off the ground together. Double check your rear springs and make sure they're both positioned correctly top and bottom within their respective struts.

[This message has been edited by Patrick (edited 10-13-2012).]

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ltlgt88
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Report this Post10-12-2012 08:05 PM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
I don't have the equipment to make the front and adjustments as of right now .just trying to get some info on the back end since that is where my spring is failing .

thanks for the info up front though

[This message has been edited by ltlgt88 (edited 10-12-2012).]

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Report this Post10-13-2012 08:47 AM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
88's have a completely different suspension setup than the 84-87, so you really need 88 specific information.

On the 88's, the front bump stops are bolted on rubber bumpers. If you lower the car, you should remove these bump stops and trim them down. Ideally, they need to be tall enough to keep the tire from making contact with the fender, but that measurement depends on wheel/tire size. Here is a picture of a stock 88 bump stop (bottom) and a modified one on top). Notice that when I cut it down, I tried to keep the overall size of the contact point the same so it will be softer when contact is made (vs. just cutting them straight across.



In the rear, to gain additional suspension travel (on compression) you can take the strut bushing plate and flip it over. In stock format, the bushing plate protrudes below the strut tower. By flipping it over, you effectively move the top of the strut shaft and the bottom of the strut bushing plate up about 1". This works for all 88's (coupes or GT's) due to location of the tops of the struts, but on the 84-87's the flipped bushing can push the top of the strut shaft into the Notchie Decklid and require additional clearance.
Here is a stock 88 rear strut bushing plate:


Here is a stock 88 bushing plate flipped (and the 88 front springs on the rear):


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ltlgt88
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Report this Post10-13-2012 09:22 AM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
FieroGuru there was only one picture attached of the front ones, don't know if it was the stock or modified. Is there a way you can attach the other picture i don't know exactly what i am looking at there.

On the rear ones on 88gt's do you have to grind any of the plates away like explained on the WCF website?

Do you suggest the WCF coil overs or the FS lowering springs? I have the FS Lowering spring right now and it is what is failing probably been on there about 10 years.

Thanks
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Report this Post10-13-2012 10:43 AM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by ltlgt88:
FieroGuru there was only one picture attached of the front ones, don't know if it was the stock or modified. Is there a way you can attach the other picture i don't know exactly what i am looking at there.


That single picture has both bump stops. The modified shorter one is physically sitting on top of the stock one in the picture. If you look close you can see the modified contour on the top one (it is about 1" shorter)


 
quote
Originally posted by ltlgt88:
On the rear ones on 88gt's do you have to grind any of the plates away like explained on the WCF website?


The 88's don't require any grinding or clearancing, just unbolt the strut shaft and flip the bushing plate over.

 
quote
Originally posted by ltlgt88:
Do you suggest the WCF coil overs or the FS lowering springs? I have the FS Lowering spring right now and it is what is failing probably been on there about 10 years.


This is really something you need to decide for yourself.
The Fiero Store springs would be the quickest/easiest to install and require no further modifications.
To put the coil overs on your Koni struts will require removing the spring perch (cutting/grinding) and clearancing (grinding) the top of the strut housings to slide the threaded sleeve over. A lot more work, but once done you could raise/lower the rear easily and have a much wider range of spring rates to pick from (200 to 400 lb/in in 25 lb/in increments).
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Report this Post10-13-2012 02:24 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by fieroguru:

88's have a completely different suspension setup than the 84-87, so you really need 88 specific information.


Sorry, I don't know how I missed that it was an '88. Yeah, quite different.

[This message has been edited by Patrick (edited 10-13-2012).]

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Report this Post10-15-2012 11:06 PM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
The coil overs that i was looking at on WCF used the original spring perch...but there would still be grinding to get the threaded sleeve onto the strut?
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Report this Post11-02-2012 11:28 PM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
bump?
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Report this Post11-03-2012 08:59 AM Click Here to See the Profile for FFIEROFREDClick Here to Email FFIEROFREDSend a Private Message to FFIEROFREDEdit/Delete MessageReply w/QuoteDirect Link to This Post
When i did my rear coil over kit their was a boot retainer plate on the top of the strut. knock it off with a hammer, side the sleeve on. I cut part of the spring purch off for tire cleaents.
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Report this Post09-07-2013 06:13 AM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
how can you tell if you are riding on your front bump stop? and how would you know how much to cut off of it to make sure you aren't rubbing the wheel well?

any guidance?

I am running 17x7.5 wheels with the FS lowering springs,, was thinking about adding the lowering ball joints too? (would this help with the ride also)?
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Report this Post09-07-2013 07:04 AM Click Here to See the Profile for BruceptsClick Here to visit Brucepts's HomePageClick Here to Email BruceptsSend a Private Message to BruceptsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Did you reset the angle of your front sway bar?

I did this on my 85GT after lowering and it greatly improved hitting the bump stop. To the point I'm not even worrying about cutting mine. My swaybar spacer ended up being 5/8" high to make the bar ends parallel to the ground.

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Report this Post09-07-2013 07:34 AM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Brucepts:

Did you reset the angle of your front sway bar?

I did this on my 85GT after lowering and it greatly improved hitting the bump stop. To the point I'm not even worrying about cutting mine. My swaybar spacer ended up being 5/8" high to make the bar ends parallel to the ground.



not that good with all this stuff won't know where to start to do that...is it easy and how?
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Report this Post09-07-2013 07:53 AM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by ltlgt88:

how can you tell if you are riding on your front bump stop? and how would you know how much to cut off of it to make sure you aren't rubbing the wheel well?

any guidance?

I am running 17x7.5 wheels with the FS lowering springs,, was thinking about adding the lowering ball joints too? (would this help with the ride also)?


One method to know how much suspension travel you have is measure the distance between your tire and fender as the car sits. Then jack it up, remove the front spring and use a jack to raise the wheel back up till it hits the bump stop. Now compare the clearance you have now vs. what you have during normal driving and that is your available suspension travel in compression. The distance between hitting the bump stop and the tire making contact with the inner fender liner is how much suspension travel you could gain back by trimming the bump stop (start by trimming 50% of the available distance, and trim more if needed). When you cut the bump stop, try to keep at least 1/4" of clearance between the tire and wheel well liner.

Here is where a stock 88 bump stop will restrict travel (205/50/16 tire):



Here is how much I trimmed the bump stop:



Here is where the bump stops now make contact:



Lowering ball joints do not change the current distance from the bumpstop to its stop, so they have very little to no impact on ride quality. That is why people like them when taking a stock fiero with stock springs and adding the lowering ball joints. They get the lowered stance in the front without any reduction of suspension travel. When you go with lowering/cut/shorter springs, you lose suspension travel under compression and greatly increase the chance of making contact with the bump stops (which makes the ride more harsh). The fix is to trim the bump stops and maximize your available suspension travel in compression. Now the one caveat to this is if you trim the bump stops to give you 1/4" clearance between tire and wheel well liner, then add the lowering ball joints, the tire will make contact with the wheel well liner under heavy compression... and that isn't good.
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Report this Post09-07-2013 08:06 AM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
Fieroguru

would you suggest going back to regular springs and just doing the lowering ball joints for better ride quality without having to cut the bump stops? what is the advantage or disadvantage of lowering ball joints vs spring? I use the car for a lot of highway and farm road cruising and am looking for a better ride, but also want great handling for mountain and curves..and maybe the every once and while autocross

I am also interested in your 13 inch break conversion...but love the look of my lowered 1inch car on 17x7.5's

If you were me and wanted to keep the car lower with your 13 brake rotor coversion what would you do? I have FS lowering springs all around right now without the ball joints, but would be willing to go back to regular springs and lowering ball joints or combo of both (different front and back, or both on same wheel)...with keeping in mind the driving i do.

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Report this Post09-07-2013 08:10 AM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post

ltlgt88

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fieroguru

or can we throw coli overs into the mix and what would you do?
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Report this Post09-07-2013 12:54 PM Click Here to See the Profile for BruceptsClick Here to visit Brucepts's HomePageClick Here to Email BruceptsSend a Private Message to BruceptsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sorry for my previous post, I just saw it's on an 88 . . .

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Report this Post09-08-2013 01:17 AM Click Here to See the Profile for ltlgt88Send a Private Message to ltlgt88Edit/Delete MessageReply w/QuoteDirect Link to This Post
so i looked at my car sitting on the ground with the wheels completely locked each way and noticed i only had less than 1/4 inch on one side above the bump stop and no clearance at all with the bump stop. So while i had the wheels turned i measured the clearance of the tire to the body and it was 1.5 inches. So if my math is right if i take 3/4 to 1 inch off each bump stop i should still have plenty of clearance to the body correct? is there any give in the bump stop i have to take into account? by making this adjustment this would give me the 1inch of travel i lost when the car was lowered correct, making my ride better for cruising and also slowing more sway in the corners for cornering?

Also doing this i will not need to do the lowering ball joints and will be able to to use FieroGuru's 13 inch rotor conversion.

Let me know if anything i said is wrong?.
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Report this Post09-08-2013 08:08 AM Click Here to See the Profile for fieroguruSend a Private Message to fieroguruEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sorry for the late reply, been at the LS Fest for the last 2 days with limited access to the internet.

I would suggest you remove both bump stops and take the car for a ride first. They are held in place with a single 13 mm nut so removal is quite quick. Take it easy with the ride and try not to hit any big bumps, but this will give you an immediate feel for the ride quality difference when you are not sitting on/hitting the bump stops continuously.

If you feel the ride is improved enough, then you can start trimming the bump stops. If you have 1 1/2" of clearance, trim 1" off on the first pass. Try too taper the new top of the bump stop so its about the same width as before so when you hit them they will compress at about the same level as stock.

Ride quality is a highly personal preference and also is largely impacted by the cars use and the local roads you take it on every day. I have never had a set of Fiero Store lowering springs, so I don't know the spring rate. Stock front is about 205 lb/in and the stock rear is about 145 lb/in. I prefer a slightly firmer ride so my LS4 car has a front spring rate about 250-275 and the rear is 275 coil overs. After doing a bunch of auto-crossing this weekend, I will likely step up the spring rates to 350/350 and hope I still like driving the car daily to work.

Coilovers in the rear are nice in that you can raise/lower the ride height with minimal impact on the geometry (mainly toe). So you don't need to get an alignment if you make a small 1" ride height change. The fronts do see a toe change so coil overs on the front would need at least a toe adjustment as you alter the ride height. Add to this bolt in coil over kits for the 88 are very rare and expensive with little room to access the adjuster w/o raising the car up on jackstands.

My 13" brake kit fits best when the car is lowered through springs. Having gone through the whole clearancing the lower A-Arm on the C4 12" rotor kit, you almost always don't take enough off, hit a big bump, and gouge the backside of the brand new rotor (which really pissed me off, especially at the time - 8+ years ago, there was no talk or mention of the interference issue, so I gouged mine as soon as I pulled the car out of the garage). The needed trimming of the lower a-arm is the whole reason I took the effort to find a better fitting rotor (12" or larger) for my car and the kit just progressed from there.
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