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Need advice 88 GT bushings and lowering by pcgold
Started on: 06-20-2015 03:49 PM
Replies: 7 (201 views)
Last post by: cptsnoopy on 06-24-2015 08:07 AM
pcgold
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Report this Post06-20-2015 03:49 PM Click Here to See the Profile for pcgoldSend a Private Message to pcgoldEdit/Delete MessageReply w/QuoteDirect Link to This Post
I can turn a wrench. That's no problem.

I have searched lots and been on Fiero Store and Rodney's websites among others.

I am looking for a list of everything I will need to:

• replace all front and rear suspension bushings (not the cradle bushings though)
• lower front 1" using RD's lowering ball joints
• lower back (not sure which method to do this though – cut spring or use a lowering spring?)
• change struts and shocks all round

Would anyone want to help me compile a list so I can get everything I need at once?

I have decided to use rubber, not poly. It’s an occasional summer driver with only 26,500miles that doesn't get driven very hard. I thought rubber would be okay for this.

I have 17” wheels so I don’t think clearance with lowering ball joints and longer zero lash end links should be an issue.

Start of list:

Front:
• Swaybar bushings
• Control arm bushings
• RD's Lowering ball joints
• RD's Long Zero lash end links
• Shocks
• Paddle Nuts

Rear:
• Sway bar bushings
• Trailing Arm bushings
• Rear Struts
• Lowering springs?

Suggestions? What else should I do while doing this?

[This message has been edited by pcgold (edited 06-20-2015).]

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cdubbz111
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Report this Post06-21-2015 07:45 PM Click Here to See the Profile for cdubbz111Click Here to Email cdubbz111Send a Private Message to cdubbz111Edit/Delete MessageReply w/QuoteDirect Link to This Post
Just personal preference here, but poly is a must for me. I realize this isn't a race car by any means, but the significance in performance change for me is huge. Just the poly sway bar bushings alone make a huge difference over stock. I'd strongly recommend you get them for the sway bar at least. On the lowering side: Cutting springs is never a good option as it modifies the total spring rate and people have had issues in the past with it. I've done it, and it makes the ride feel to bouncy even with better than stock shocks. Look in to a custom coil-over setup. You'd be looking at only a 100-200 more over your current setup to have more tune-ability. Or you can buy lowering springs but then your stuck at that height and have no options. Just my two cents though. Best of luck on the build!
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olejoedad
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Report this Post06-22-2015 10:09 AM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Cutting springs properly is many times the BEST option for lowering a car.
Cutting springs raises the spring rate only slightly (10 - 20%, depending on amount removed), while most lowering springs increase spring rate 35 - 100%.
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Fiero Vice
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Report this Post06-22-2015 10:52 AM Click Here to See the Profile for Fiero ViceSend a Private Message to Fiero ViceEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by olejoedad:

Cutting springs properly is many times the BEST option for lowering a car.
Cutting springs raises the spring rate only slightly (10 - 20%, depending on amount removed), while most lowering springs increase spring rate 35 - 100%.


Interesting! Cutting springs would increase spring rate? I've read how Fiero owners cut it to lower it. It's a good thing I read your comment.
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Blacktree
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Report this Post06-22-2015 11:05 AM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post
When you cut coils off a spring, it makes the spring less compliant (i.e. stiffer). So yeah, cutting your stock springs will increase the spring rate.

[This message has been edited by Blacktree (edited 06-22-2015).]

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thesameguy
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Report this Post06-22-2015 03:08 PM Click Here to See the Profile for thesameguyClick Here to Email thesameguySend a Private Message to thesameguyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Indeed. Cutting springs has a predictable effect on spring rate -

Spring Rate=(G*d^4)/(8*n*D^3)

Where:
G=11 (5x10^6 for steel springs)
d is the wire diameter in inches
n is the number of active coils
D is the mean diameter which is equal to the outer diameter minus the wire diameter

The increase in spring rate is directly proportional to the number of coils cut.

The potential problem with cutting coils is that unless your front springs and rear springs are the same, you may have a hard time getting desirable results cutting because each cut front and rear will have a different effect on spring rate. You may end up driving up one spring rate faster than the other. Or, I guess, end up with an even car trying to maintain relative spring rates.

You can certainly try it, it costs pretty much nothing but time to give it a go... but on the other hand don't expect "professional quality" results from a cut.
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hnthomps
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Report this Post06-23-2015 10:16 PM Click Here to See the Profile for hnthompsClick Here to Email hnthompsSend a Private Message to hnthompsEdit/Delete MessageReply w/QuoteDirect Link to This Post
You may also want to consider coil overs for the rear of the car.

Nelson
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cptsnoopy
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Report this Post06-24-2015 08:07 AM Click Here to See the Profile for cptsnoopyClick Here to Email cptsnoopySend a Private Message to cptsnoopyEdit/Delete MessageReply w/QuoteDirect Link to This Post
First question, are you upgrading or have you already upgraded to 12" corvette brakes? If so, the 1" lowering ball joints will cause the LCA to rub on the rotor. An alternative is to go with the 13" brakes but be sure your wheels will still fit over them. Stock brakes should be fine.

I'd use rubber if you can find it for all bushings but poly is definitely not the end of the world. My 88 has all poly, I just gobbed on the grease and it seems to ride ok. I found it difficult to find rubber bushings.

Rodney's endlinks are great!

Getting replacement paddle nuts is a good insurance policy.

For the rear, I had to use coilovers because of my engine swap and the reduced amount of room I ended up with. They are fine but I suspect lowering springs or cut springs ride just as well. You just give up the ability to fine tune the height. You may want to look into flipping the top hat to regain the inch of travel on the up stroke.
Regarding coilovers, you will need to use a centering sleeve for the top of the spring or something that does the same job. Plus, you will need to figure out a way to keep dust/dirt/debris off of the shock shaft as it will ruin the seal much quicker otherwise. I am using a dust cover over my springs and I am hoping that will do the job.

One last thing, you may be interested in Fiero Guru's trailing link relocation kit (I hope I called it the correct name) It returns the rear geometry closer to stock on lowered rears.

Good luck!

Charlie
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