Cause of sudden ride hight and camber change.
#31
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Scott ,The 1980 has Eibach progressive springs besides I have trimmed down to a svelte 330 lbs. I don't need no stinking wings for downforce !
#32
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Originally Posted by Schocki
If you start playing with ride height setups and so on you could possibly turn things to the better. But also you could get things further out of alignment and when you finally go for a 4 wheel alignment you don't know the first cause of the problem was..
I think people are scared to touch the 928's ride geometry because of the horror stories they've heard about bad alignments. I have the benefit of having taken my entire front and rear suspension apart this past winter, so I understand now how the various settings work together. It's not rocket science. After you fix the ride height, the key will be to make sure your camber is within reasonable spec (I'd say slightly negative from spec as you don't track it), and then front toe.
My front toe is still a little off, but within reason. Tires have worn well from what I can tell on the trip to SITM and back. I noticed that my steering wheel is slightly off to the left so I'll probably crank the tie rods a 1/4 turn to straighten. Once you read Capt Earl's write up and putz around with his set up, I think you quickly learn how the geometry is affected by the various adjustments that can be made on the 928.
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I strongly disagree with raising the ride height and aligning the car in its present condition.
Fact 1 Ride height has fallen dramatically by itself within the last six months.
Fact 2 The addition of a tank of gas causes a 10mm fall in suspension height!!!
Fact 3 Camber is way off and the car is eating tires like popcorn.
IF the ride height adjustment will allow the car to be raised enough (BIG IF), it will be at or near the end of its travel and the underlying cause of the problem will not have been addressed. If the car is aligned without addressing the underlying cause of the suspension problem the problem will get worse and recur.
Fact 1 Ride height has fallen dramatically by itself within the last six months.
Fact 2 The addition of a tank of gas causes a 10mm fall in suspension height!!!
Fact 3 Camber is way off and the car is eating tires like popcorn.
IF the ride height adjustment will allow the car to be raised enough (BIG IF), it will be at or near the end of its travel and the underlying cause of the problem will not have been addressed. If the car is aligned without addressing the underlying cause of the suspension problem the problem will get worse and recur.
#34
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Ernest-
Maybe i wasn't clear. If the cause for the sudden drop can be identified, then it MUST BE ADDRESSED FIRST! No question there.
My suggestion about raising ride height is assuming that everything else checks out. You will not be able to get an accurate/proper alignment with a car that is not within spec on the ride height. So that's the first step to tackle after any mechanical failure is addressed.
So I think we're one the same page, but I might be reading ahead . Let us know what you guys find out.
Maybe i wasn't clear. If the cause for the sudden drop can be identified, then it MUST BE ADDRESSED FIRST! No question there.
My suggestion about raising ride height is assuming that everything else checks out. You will not be able to get an accurate/proper alignment with a car that is not within spec on the ride height. So that's the first step to tackle after any mechanical failure is addressed.
So I think we're one the same page, but I might be reading ahead . Let us know what you guys find out.
#37
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Roger,
For a reference point to your rear suspension, the attached pic is of my '88 S4. I believe it to be identical to yours, except for the use of Konis. The springs are OEM two blue stripe, with wire diameter of 14mm and inter coil spacing of 20mm. The threaded bushing bottom to slotted collar flange is 36.5mm, yielding a rear height of 170mm.
Taken that your upper mounts are good and the springs have all the coils (OEM), then only two things can influence the ride height. Firstly is the adjuster position, and yours appears to be ~10mm lower. Secondly would be spring fatigue - and that would be seen as a lesser inter coil spacing. So you may compare ...
From your pics, Jim is (again) spot on re front toe being excessive. The severe feathering indicates that your car if plowing down the road leaving a trail of rubber dust: you will be amazed as how free running your car feels once the toe is correctly set - it will be as if you cut the rope to a huge anchor ....
Excuse a hijack, but look closely at my adjuster nut - some dummy installed it bassackwards when the Konis went in. The spring perch should center on the lip exposed below the slotted collar.
Is it necessary to correct this stupid error ( risk of the lower perch touching the shock body), or can I live with it? I wouldn't have caught this treasure unless looking for the measure quoted above ..... so thanks - I think ...
For a reference point to your rear suspension, the attached pic is of my '88 S4. I believe it to be identical to yours, except for the use of Konis. The springs are OEM two blue stripe, with wire diameter of 14mm and inter coil spacing of 20mm. The threaded bushing bottom to slotted collar flange is 36.5mm, yielding a rear height of 170mm.
Taken that your upper mounts are good and the springs have all the coils (OEM), then only two things can influence the ride height. Firstly is the adjuster position, and yours appears to be ~10mm lower. Secondly would be spring fatigue - and that would be seen as a lesser inter coil spacing. So you may compare ...
From your pics, Jim is (again) spot on re front toe being excessive. The severe feathering indicates that your car if plowing down the road leaving a trail of rubber dust: you will be amazed as how free running your car feels once the toe is correctly set - it will be as if you cut the rope to a huge anchor ....
Excuse a hijack, but look closely at my adjuster nut - some dummy installed it bassackwards when the Konis went in. The spring perch should center on the lip exposed below the slotted collar.
Is it necessary to correct this stupid error ( risk of the lower perch touching the shock body), or can I live with it? I wouldn't have caught this treasure unless looking for the measure quoted above ..... so thanks - I think ...
#38
Originally Posted by ErnestSw
I strongly disagree with raising the ride height and aligning the car in its present condition.
Fact 1 Ride height has fallen dramatically by itself within the last six months.
Fact 2 The addition of a tank of gas causes a 10mm fall in suspension height!!!
Fact 3 Camber is way off and the car is eating tires like popcorn.
IF the ride height adjustment will allow the car to be raised enough (BIG IF), it will be at or near the end of its travel and the underlying cause of the problem will not have been addressed. If the car is aligned without addressing the underlying cause of the suspension problem the problem will get worse and recur.
Fact 1 Ride height has fallen dramatically by itself within the last six months.
Fact 2 The addition of a tank of gas causes a 10mm fall in suspension height!!!
Fact 3 Camber is way off and the car is eating tires like popcorn.
IF the ride height adjustment will allow the car to be raised enough (BIG IF), it will be at or near the end of its travel and the underlying cause of the problem will not have been addressed. If the car is aligned without addressing the underlying cause of the suspension problem the problem will get worse and recur.
#40
Originally Posted by ErnestSw
I would think that as long as the spring perch sits on the nut squarely and securely you'll be fine.
It would be a hassle, but you could at least mark where the nuts are now and just screw them back to the same physical location.......so ride height wouldn't change.
#41
I've been reading all these posts & I think I definately have a problem with my front ride height as well. I switched from the 16" flat dishes to 16" C2 5 spoke wheels a couple of months ago, but I didnt notice any difference in the ride height afterwards. The past few weeks, I have begun to notice the car sitting low on the tires, I could barely place my hand between the tire & the fender. Then I began to notice that on the front passenger side that in certain instances when turning left, the tire occasionally rubs slightly on the wheel well. Im certain it wasnt this way until the past few weeks.
At SITM, DR noticed my low rider look & told me to raise the height, that it was way too low. Well, after having to jack up my car & put it on stands Sunday am to replace the ac belt, my Shark had the normal wait for the front end to settle back down. I didnt pay so much attention to how it settled until that afternoon as we began the trip back home. It now definately has more clearance above the driver's front tire than the passenger front.
I know I should be in the millimeter specs, havent had any chance to measure anything, drove it home parked it and covered it. But I did do the unscientific measurement of trying to place my hand palm up in between the outside of the tire & the fender. The drivers side I can place my fingers all the way in up to the knuckles of my hand, on the passenger side, I can only make it to the 2nd knuckle on my fingers. I can see everyone shaking their heads & snickering at me, but that is the best I can do for now. Just didnt want this thread to die before I threw out my current ride height delima for advice too. THANKS!
At SITM, DR noticed my low rider look & told me to raise the height, that it was way too low. Well, after having to jack up my car & put it on stands Sunday am to replace the ac belt, my Shark had the normal wait for the front end to settle back down. I didnt pay so much attention to how it settled until that afternoon as we began the trip back home. It now definately has more clearance above the driver's front tire than the passenger front.
I know I should be in the millimeter specs, havent had any chance to measure anything, drove it home parked it and covered it. But I did do the unscientific measurement of trying to place my hand palm up in between the outside of the tire & the fender. The drivers side I can place my fingers all the way in up to the knuckles of my hand, on the passenger side, I can only make it to the 2nd knuckle on my fingers. I can see everyone shaking their heads & snickering at me, but that is the best I can do for now. Just didnt want this thread to die before I threw out my current ride height delima for advice too. THANKS!
#42
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Hey Mel,
The same principle applies to your suspension as Roger's. If there's been a noticeable fall in ride height the only cause is sagging springs.
It's interesting to note that your problem also seemed to develop over a fairly short period of time. I wonder whether spring sag tends to accelerate once it begins.
The same principle applies to your suspension as Roger's. If there's been a noticeable fall in ride height the only cause is sagging springs.
It's interesting to note that your problem also seemed to develop over a fairly short period of time. I wonder whether spring sag tends to accelerate once it begins.
Last edited by ErnestSw; 06-09-2005 at 01:03 AM.
#43
So if its the springs, then I should change the springs & shocks only? If changed a shock or two in my time, but changing the springs, is that something I should leave to the more experienced??
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The suspension uses a coilover spring shock combination in which the spring is actually mounted on the shock. You'll have to use a spring compressor to assemble the coilover, but removal and reinstallation of the assembled unit is fairly simple.
#45
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Originally Posted by ErnestSw
and reinstallation of the assembled unit is fairly simple.
Removal is easy (except for those damn spring perches from the old shocks ). Reinstallation is pretty easy on the back as long as you can get the bolts to line up in the rear hatch mounting points. Fronts, that's a different story.
The fronts come right out! Really they do. They drop right out of the upper control arm, but getting them back in is like one of those damn metal ring puzzles that if you don't have everything angled just right, it won't go. Very frustrating. I almost took the upper a-arm off, but then saw where the bolts were and percevered. Doable, but make sure the kids aren't around to hear you cuss up a $hit storm!