S4 or GT Springs
#31
Nordschleife Master
i wouldnt pay anything for 20K mile 11 year old suspension parts
You probably need dampers, springs could be replaced but no way to know unless you put them on a dyno.
The spongy feel you describe is most likely a damper that isnt dampening anymore
see the thread posted on GT shocks in a low mile car that are toast, dampers are an age issue not in most circumstances a mileage one.
You probably need dampers, springs could be replaced but no way to know unless you put them on a dyno.
The spongy feel you describe is most likely a damper that isnt dampening anymore
see the thread posted on GT shocks in a low mile car that are toast, dampers are an age issue not in most circumstances a mileage one.
#32
Archive Gatekeeper
Rennlist Member
Rennlist Member
I agree with Ryan- buy new.
Accoridng to the PET, GTS front springs are 928 343 511 09, marked brown, while rears are 928 333 531 14, marked with 1, 2, or 3 blue marks.
FWIW, My '90 GT has original springs all around, which are the exact same #'s as what's listed for GTS's - 09's up front with 3 brown markings, and 14's in back, with 1 blue stripe. The car has 109K miles on these springs, which i will be replacing soon along with new Boge Reds.
I recently bought some CS springs for my '90 GT which are 928.343.511.12.504. with 2 orange stripes, and rear springs 928.333.531.14, makred with 1 blue stripe.
Front shocks:
Rear Shocks:
Front CS springs:
Rear Springs:
Accoridng to the PET, GTS front springs are 928 343 511 09, marked brown, while rears are 928 333 531 14, marked with 1, 2, or 3 blue marks.
FWIW, My '90 GT has original springs all around, which are the exact same #'s as what's listed for GTS's - 09's up front with 3 brown markings, and 14's in back, with 1 blue stripe. The car has 109K miles on these springs, which i will be replacing soon along with new Boge Reds.
I recently bought some CS springs for my '90 GT which are 928.343.511.12.504. with 2 orange stripes, and rear springs 928.333.531.14, makred with 1 blue stripe.
Front shocks:
Rear Shocks:
Front CS springs:
Rear Springs:
#33
Guys, thanks for the advice. These parts are going to be fairly cheap to buy. even assuming the dampers were no good. I would think it would still be a good buy just for the springs providing the GT/GTS spec springs are higher rated over the std S4 items, do you know if this is the case ?? So are the Boge reds the so called "Club sport" option I keep reading about? Thanks for the pics Rob.
#34
Nordschleife Master
well depends on how cheap, they would make nice paper weights for $150. I wouldnt pay more then $150 considering NEW eibachs are $300. The dampers arent worth anything, seriously, they are crap, so if you bought everything, your paying for springs, which are probably fine. But I was looking at an Excellence article in 1990 testing the new 928 and they mentioned specifically that they thought the front end was under sprung, the car bottoms out, which many of us can attest to, hell, there are a number of people that have had to scrap engines completely cause of this type of SERIOUS damage.
I dont know a whole lot about suspension stuff but if your going to upgrade, then truly upgrade, i think the 928 would be well served with firmer springs and a damper that correctly matches the spring weight and the the weight of the car and all the factors that go into determining such things.
How cheap is cheap? I am sure if he sold you on the fact that it was a 20K mile car hes got you in the eather so to speak. So is is obvioulsy not giving these away. Other then the springs the top spring perch is worth something although when you replace these you just reuse the old one. They are worth something, but i dont think you get ANY value out of it as you really should use only new dampers.
I dont know a whole lot about suspension stuff but if your going to upgrade, then truly upgrade, i think the 928 would be well served with firmer springs and a damper that correctly matches the spring weight and the the weight of the car and all the factors that go into determining such things.
How cheap is cheap? I am sure if he sold you on the fact that it was a 20K mile car hes got you in the eather so to speak. So is is obvioulsy not giving these away. Other then the springs the top spring perch is worth something although when you replace these you just reuse the old one. They are worth something, but i dont think you get ANY value out of it as you really should use only new dampers.
#36
Yep, Its only a matter of time on the bumpy crappy uk roads before my sump whacks into the tarmac. Hes asking £300 (sterling) for the GTS units, $300 for the Eibachs! Please can you tell me where to get them even with the shipping that sounds very reasonable? Where would you go for the Boge dampers?
#37
Nordschleife Master
#38
Nordschleife Master
300GBP is too much for used dampers, thats what your paying for and i doubt they would be any good, just walk away. Seriously, just buy new, AGAIN, why pay near new price for 10 -15 year old dampers!
what year model are you thinking of using the springs for? What makes you think you need new springs at all?
what year model are you thinking of using the springs for? What makes you think you need new springs at all?
#40
Nordschleife Master
i read through your original post, your "bouncy" is most likely JUST dampers. Ive heard springs sag but there are more cars with original springs then with replaced ones. Try dampers, a worn damper wont properly dampen the spring oscilations. The spring is fine, its the damper thats shot.
#42
Nordschleife Master
you can adjust the ride height, ask Rob hes done it a few times, i havent.
from your first post you seemed to be mostly interested in fixing the bouncy ride, bouncy ride is damper, cosmetically and for other reasons i am sure you replace the springs. Honestly when i replace my shocks i will do the springs just as a while i am there thing, but i dont think they are a mandatory replacement, but if youve got it in the budget then get new springs. But dont replace your dampers with used ones, i am beating a dead horse here but dont do that.
from your first post you seemed to be mostly interested in fixing the bouncy ride, bouncy ride is damper, cosmetically and for other reasons i am sure you replace the springs. Honestly when i replace my shocks i will do the springs just as a while i am there thing, but i dont think they are a mandatory replacement, but if youve got it in the budget then get new springs. But dont replace your dampers with used ones, i am beating a dead horse here but dont do that.
#44
Archive Gatekeeper
Rennlist Member
Rennlist Member
Yes, ride height adjustment is really easy, so I would start there.
If your ride height is very low (which takes 3 minutes to measure, make a set of these out of coat hanger:
And measure at the factory points (here's the rear point, right at 173 mm, and a shot of the front left wheel's measuring point, should be 180 mm off the ground) There are plenty of posts on the value of having the correct ride height, for both suspension geometry and front spoiler/A/C compressor/engine block preservations reasons!
If you're indeed way low on the ride height, and you're SURE that no one's adjusted your spring perches before, then your springs have obviously settled.
DISCLAIMER: I don't know jack about suspension design, geometry, etc, so take this with a grain of salt, but it seems to me that if a spring has sagged, then of course its free length has decreased, but has its spring rate changed? I just wonder what happens when you crank up the ride height on sagged springs, how does that effect the spring rates (and ultimately the stability of the car over bumps, pavement transitions, etc.) ??? My guess is that at some point, if you're driving the car aggressively or on track, really worn springs and shocks becomes a safety issue.....
If your ride height is very low (which takes 3 minutes to measure, make a set of these out of coat hanger:
And measure at the factory points (here's the rear point, right at 173 mm, and a shot of the front left wheel's measuring point, should be 180 mm off the ground) There are plenty of posts on the value of having the correct ride height, for both suspension geometry and front spoiler/A/C compressor/engine block preservations reasons!
If you're indeed way low on the ride height, and you're SURE that no one's adjusted your spring perches before, then your springs have obviously settled.
DISCLAIMER: I don't know jack about suspension design, geometry, etc, so take this with a grain of salt, but it seems to me that if a spring has sagged, then of course its free length has decreased, but has its spring rate changed? I just wonder what happens when you crank up the ride height on sagged springs, how does that effect the spring rates (and ultimately the stability of the car over bumps, pavement transitions, etc.) ??? My guess is that at some point, if you're driving the car aggressively or on track, really worn springs and shocks becomes a safety issue.....
#45
Thanks guys. Im going to measure it this week, just to see if the springs have sagged. Although my fronts (grey colour) dont have any adjustment ring. But for approx £150 sterling I will probably go for the Eiabachs anyway.