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Raising up front suspension with coilovers by Rare87GT
Started on: 12-17-2003 10:06 PM
Replies: 24
Last post by: Rare87GT on 12-24-2003 05:27 PM
Rare87GT
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Report this Post12-17-2003 10:06 PM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post
I currently have Held motorsports front coilovers and rears. My question is on the front coilovers can I raise it up without compressing the spring or taking the spring and strut out? I need to raise it a few turns because right now it hits the fender well and the tire on hard bumps and is ruining my tires and fenderwell. Can anyone help me out here. Thanks


-Amir

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Maroon 1987 GT 5 spd: 2.8L
Ferrari Red 1988 Formula 5 spd: 3800 Series II Supercharged In & Running.....
Need any parts? Got 2 parts cars:
86GT 4spd
87 Coupe 4cyl

My Website: http://www.members.cox.net/rare88/

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Rare87GT
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Report this Post12-18-2003 12:09 AM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post
Anyone know?
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Kameo Kid
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Report this Post12-18-2003 12:13 AM Click Here to See the Profile for Kameo KidSend a Private Message to Kameo KidDirect Link to This Post
i dont have them on my GT but I think that all you have to do is jack the car up so that the weight of the car is off the springs, then you can ajust the locking washers on the bottom of the coilover.

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3.4 DOHC Turbo swap in progress

[This message has been edited by Kameo Kid (edited 12-18-2003).]

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madcurl
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Report this Post12-18-2003 12:21 AM Click Here to See the Profile for madcurlClick Here to Email madcurlSend a Private Message to madcurlDirect Link to This Post
Sure....if you're superman! Raise the car first and use the tool for turning the coil over. i have them and you have to raise the car. Don't forget the allen-loc thread on them. It won't move unless you loosin the thread.

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Rare87GT
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Report this Post12-18-2003 12:21 AM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post
 
quote
Originally posted by Kameo Kid:

i dont have them on my GT but I think that all you have to do is jack the car up so that the weight of the car is off the springs, then you can ajust the locking washers on the bottom of the coilover.


I tried that and the locking washers wouldn't turn. It seemed there was still compression on the springs allowing it not to turn. Anyone else familiar with front coilovers. Have you guys ever heard of spring inserts to raise the heighth a little. I think they sell them at Autozone but I just never heard of them, anyone have any clues?

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Rare87GT
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Report this Post12-18-2003 12:26 AM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post

Rare87GT

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quote
Originally posted by madcurl:

Sure....if you're superman! Raise the car first and use the tool for turning the coil over. i have them and you have to raise the car. Don't forget the allen-loc thread on them. It won't move unless you loosin the thread.


What is the tool for turning the coilovers? Also why I was underneath I noticed that my front coilover springs are 325lbs springs and my rears are 250lbs springs. Is that bad to have higher spring rates in the front?

[This message has been edited by Rare87GT (edited 12-18-2003).]

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madcurl
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Report this Post12-18-2003 01:39 AM Click Here to See the Profile for madcurlClick Here to Email madcurlSend a Private Message to madcurlDirect Link to This Post
Are you sure you're loking at it correctly? 325 rate in back and 250 in front? Right? Anyway the tool I use is from Helds...about 15-25 bucks I think? Its only needed for the fronts due to the spring extended (depend upon what height of spring). Taller the spring the greater strenght needed to turn it. Make sure you count the turns during the prceedure.

Bwy, I hope your reading it the wrong way otherwise you have the springs backwards. 250 rate in the rear would bottom out and 325 should be in the rear. Mine are 185's (I think) in the fronts and 300's in the back (10" lenght). I need to go up by 25-50...maybe a 350 rate. The fronts are okay.

Songman has a pic of the rear springs. Call Lee for more imfo on your situation.

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Rare87GT
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Report this Post12-18-2003 03:27 AM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post
Yeah 325lbs in the front is what it said on the little tag on the spring and then I have 250lbs springs in the rear. My rear doesn't budge at all but I can barely at least move the front some. Let me know. Thanks.


-Amir

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cowans
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Report this Post12-18-2003 09:40 AM Click Here to See the Profile for cowansClick Here to Email cowansSend a Private Message to cowansDirect Link to This Post
I believe your springs should be reversed... front><rear! The heavier springs should be in the rear. When changing your ride height, keep in mind that you may require an alignment after.(toe adjustment will change) Springs are difficult to 'crank' up, so the car definitely needs to be off the ground.(car weight off of wheels) A little oil goes a long way on the adjustment threads. For racers(who are constantly adjusting) there are NEW rollors races that are placed inbetween the adjustment ring and spring....allows the ring to easily screw up or down! What the previous note say, loosen any lock screws, count your turns, make sure both sides are equal! Moroso make a spring adjustment tool that will fit/adjust to any coilover, decent but expensive!
Sandy
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Report this Post12-18-2003 11:59 AM Click Here to See the Profile for NashcoClick Here to visit Nashco's HomePageClick Here to Email NashcoSend a Private Message to NashcoDirect Link to This Post
Heavier springs should not be in the rear. The front uses heavier springs because the control arm acts as a lever on the spring, thus the wheel rate in the front is lower than it is in the rear despite the higher spring rate in the front. The rear spring is on the strut, therefore it's basically a 1:1 wheel rate to spring rate ratio. The front control arms have the springs about in the middle, so there's approximately 1:2 wheel rate to spring rate.

To adjust the fronts, the procedure is the same as the rears. Jack it up, put the jackstands under the frame (NOT the control arms), loosen the set screw that holds the adjuster nut in place, hold/clamp the adjuster thread, use your adjuster wrench to spin the adjuster nut. Adjust the left and right sides the same amount of turns, tighten the set screws, put it back on the ground.

Bryce
88 GT

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cowans
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Report this Post12-18-2003 01:09 PM Click Here to See the Profile for cowansClick Here to Email cowansSend a Private Message to cowansDirect Link to This Post
 
quote
Originally posted by Nashco:

Heavier springs should not be in the rear. Bryce
88 GT

Ok! I must be mistaken.... Normally, springs are placed to compensate for the amount of weight...geometry aside! In my case, I have more weight in the rear! So, while I don't have 'Helds' setup, I definately have heavier springs in the rear...along with my V8! My fronts=275lb, rears=450lb(+4"per side,widetrack)
works for me!
Sandy

[This message has been edited by cowans (edited 12-18-2003).]

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madcurl
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Report this Post12-18-2003 02:17 PM Click Here to See the Profile for madcurlClick Here to Email madcurlSend a Private Message to madcurlDirect Link to This Post
Hmmmmm......did you check/call Helds/lee on this?
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Rare87GT
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Report this Post12-18-2003 05:25 PM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post
 
quote
Originally posted by madcurl:

Hmmmmm......did you check/call Helds/lee on this?


He said I need to get the 325lbs springs and the KYB struts. He says that I would need to get the bigger spring rate for my engine swap.

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Rare87GT
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Report this Post12-18-2003 05:26 PM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post

Rare87GT

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So do I definitely need the tool then for turning the adjuster nut for the fronts?
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animuL
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Report this Post12-18-2003 05:33 PM Click Here to See the Profile for animuLClick Here to Email animuLSend a Private Message to animuLDirect Link to This Post
bump
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Report this Post12-18-2003 07:00 PM Click Here to See the Profile for iluvmacsClick Here to visit iluvmacs's HomePageClick Here to Email iluvmacsSend a Private Message to iluvmacsDirect Link to This Post
 
quote

Ok! I must be mistaken.... Normally, springs are placed to compensate for the amount of weight...geometry aside!

Yes, you are mistaken. The springs are placed in the middle of the A-arm travel, which means that where the springs are, there is half as much torque as there is on the wheel. For this reason, twice the actual spring rate required should go there.

This isn't exact, because it's not exactly halfway, and in the rear the spring isn't directly over the wheel (that's impossible). To get the correct spring rate it's best to take the rates from the manufacturer, then based on your driving habits, change the spring rate accordingly. I'm assuming that the spring rate changes with the coilover height setting. The only problem is that if you bought the wrong springs, to get the right rate you're ride height is going to be either really high or really low.

Good luck finding the tool to move the coilovers. If those things are made of steel, might they have rusted?

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madcurl
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Report this Post12-18-2003 08:33 PM Click Here to See the Profile for madcurlClick Here to Email madcurlSend a Private Message to madcurlDirect Link to This Post
So did you tell Lee about the 250 rear and 325 fronts? Backwards or what? Did they send you the wrong or right combination?
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Nashco
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Report this Post12-19-2003 02:25 AM Click Here to See the Profile for NashcoClick Here to visit Nashco's HomePageClick Here to Email NashcoSend a Private Message to NashcoDirect Link to This Post
 
quote
Originally posted by Rare87GT:

So do I definitely need the tool then for turning the adjuster nut for the fronts?

You can use a big pair of channel locks or oil filter pliers if you want to gall up the nut. The tool costs less than 10 bucks, you can get one at most motorcycle shops or anywhere that sells high performance suspension parts. It will last you a lifetime and makes the job much easier. I'm sure Summit/Jegs has one super cheap.

Bryce
88 GT

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Rainman
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Report this Post12-19-2003 02:46 AM Click Here to See the Profile for RainmanSend a Private Message to RainmanDirect Link to This Post
 
quote
Originally posted by Nashco:

Heavier springs should not be in the rear. The front uses heavier springs because the control arm acts as a lever on the spring, thus the wheel rate in the front is lower than it is in the rear despite the higher spring rate in the front. The rear spring is on the strut, therefore it's basically a 1:1 wheel rate to spring rate ratio. The front control arms have the springs about in the middle, so there's approximately 1:2 wheel rate to spring rate.

What's this?! A sign of intelligent life on PFF?! Nashco, just when I was feeling there was little hope for this place after reading a different thread, I see your post. BTW: I have the actual suspension ratios here if anyone is interested.

Yes, you will most likely need to get a wrench to turn the nut to compress the spring. IF you don't want to mar the nut.

[This message has been edited by Rainman (edited 12-19-2003).]

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iluvmacs
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Report this Post12-19-2003 09:41 AM Click Here to See the Profile for iluvmacsClick Here to visit iluvmacs's HomePageClick Here to Email iluvmacsSend a Private Message to iluvmacsDirect Link to This Post
What are they, I'm interested.

BTW, where is "The police state of ohio"?

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Rainman
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Report this Post12-19-2003 10:19 AM Click Here to See the Profile for RainmanSend a Private Message to RainmanDirect Link to This Post
Apple guy, I'm in the Dayton area. I recognize the name Elyria, but have no idea where it is.

I have a bunch of my stuff packed, but I found one of my notes stating rates for the '88 front as:
spring rate: 205.6lb/in
rate at wheel: 75.38lb/in

EDIT: The above numbers are taken directly from the MVMA manual.

Sooooo, take 205.6 / 75.38 = 2.72 = 1:2.72 as the suspension ratio for the front. I've been up all night, and my flight leaves in a few minutes, so if I screwed up the match it shouldn't be hard to correct.
The rear I have at home, and can get when I get back in 1.5 weeks. It should be close to 1:1, at least for the '88s, I'm not familiar with the pre '88 cars.

I'm currently prepping my car for more racing this upcoming season, so I've been doing a lot of math to make sure I have this thing balanced as well as possible.

[This message has been edited by Rainman (edited 12-19-2003).]

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Will
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Report this Post12-19-2003 10:39 PM Click Here to See the Profile for WillClick Here to Email WillSend a Private Message to WillDirect Link to This Post
First, motion ratio is the square of mechanical advantage. So if the spring is halfway out on the control arm, then the mechanical advantage is 2, and the motion ratio is 4. The wheel rate is then 1/4 of the spring rate.

Despite all this, the stiff springs should STILL be on the rear. 325 rear with 250 front is a good combo if you have your tires properly staggered front to rear.

The adjusting collar probably has a set screw in it which tightens down on the threaded sleeve. Find that screw and loosen it, then you will be able to turn the adjusting nut. Turn the adjusting nut, set the car down and check the height, repeat.

If you're interested in looks, measure both sides to achieve the same wheel house gap on each side; if you're interested in performance, you're going to need to have the car cornerweighted. Don't forget to settle the suspension when you set it down to check to see if you have the correct height and weight.

Once you have the heights and weights where you want them, tighten the set screw back down and have the car aligned.

[soapbox]
What coil-overs are REALLY for is cornerweighting the car... adjusting the amount of spring load at each corner so that the diagonal weight distribution is 50/50 and the car has no wedge. Coil overs are NOT supposed to be for lowering the car significantly. They should only be used to make small adjustments to ride height.
[/soapbox]

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'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

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Report this Post12-20-2003 10:58 AM Click Here to See the Profile for AzrielSend a Private Message to AzrielDirect Link to This Post
I have no idea what the spring rates should be, or which should be the stronger spring. I'm just camping out in this thread cause I know this is gonna trun ugly soon, and I don't want to miss it. =P

While I'm here, though, where's a good place to get coilovers?

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Report this Post12-22-2003 09:03 AM Click Here to See the Profile for cowansClick Here to Email cowansSend a Private Message to cowansDirect Link to This Post
Well, regardless of the geometry of comparing where the front shock is located, I still maintain the heavier springs will go on the rear! Apparently 'Will' agrees. To the originator of this page 'Rare87GT', I would be all over Held for the proper info... I believe if you use 325+ springs in the front you will have a 'POGO' effect for suspension! Sandy
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Rare87GT
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Report this Post12-24-2003 05:27 PM Click Here to See the Profile for Rare87GTClick Here to Email Rare87GTSend a Private Message to Rare87GTDirect Link to This Post
So I guess having 325lbs springs in the front means that the springs could have been switched by accident? Could that be a possibly? Or are the front springs different height sizes compared to the rears? Is it really bad then to have 325lbs springs in front or is that not unheard of? Just wanting some more info, I mean if it is that easy I can move the fronts to the rear and the rears to the front and have 325lbs in the rear and 250lbs in the front. Let me know guys. Thanks.

Nashco, Will both of your inputs are always well informed and helpful and you Rainman.


-Amir

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