Coilover with unbearable harshness

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
Hey guys, i have installed a set of strange 10 way coilovers on my 03 cobra and the ride quality has diminished to the point that i dread driving it to work every morning.

A little about my car's mods: full length subframe connectors, UPR K member, UPR tubular A-arms, 250lb x 12" springs with Stange 10 way single adjustable struts, maximum motorsports 4 bolt CC plates.

Everything is installed according to manufactures specs for each item and I have triple checked everything. This is why I have resorted to posting here for advice.

I live in Hawaii and the roads are crap. Potholes everywhere and uneven roads for rain runoff.

I thought coilovers would help by providing a smoother, more natural geometry for the front suspension, but i seem to be wrong. I heard bangs, thumps, and just pure chaos driving around.

I knew that having spherical bearings and polyurethane bushings can increase NVH, but i feel like it shouldn't be this bad.

I found some resent info that strange struts are undersized to fit more manufacturers CC plates, so i measured them with my Starrett calipers and the were in fact 11 thousands undersized. I took some shim stock to take up tge difference and that seened to help some, but only by about 5% difference in noise.

I guess my question, before i put all my stock suspension back on is, is this normal? Do they make any coilover spring isolators or top spring perch isolators (something that would go between the CC plate and coilover to absorb the vibrations)?
 

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
Also, i have verified i have the correct number of spacers above and below the CC plates and that there is no metal to metal contact between the upper coilover spring "hat" and the CC plates. I have also used the recommended torque spec for the strut nut and also tried "much more torque" as others have suggested.
 

GNBRETT

Well-Known Member
Established Member
Premium Member
Beer Money Bros.
Joined
Oct 14, 2010
Messages
4,548
Location
Middle Earth
U need double adjustable shocks so u can change both the compression and rebound otherwise it will be a stiff pogo stick. These only allow rebound. Ur getting no compression setting and without a compression setting ur ride is gonna be shitty.

I had single adjustables and no mater what I did it rode like shit. Worked great at the drag strip but rough on the street.

I ended up going with Viking crusaders in DA and I can now set my shocks to be very comfortable on the street and when I get to the track I just make a few clicks to stiffen them up. Take less than 5 minutes to do all 4 sides.
 

Blkkbgt

Well-Known Member
Established Member
Premium Member
Joined
Feb 3, 2011
Messages
3,075
Location
The land of commies and socialists!
I have seldom come across people who have little or zero complaints about strange coilovers. They seem to be some of most noisy setups out there.

With that said is the car slammed? If you adjusted them all the way down you'll have minimal if any bump travel. When you hit a pot hole or your suspension goes full droop the spring will become un-seated and momentarily pop out of its perch. This is one of the most common causes of complaints I see with coilovers.
 

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
Blkkbgt, thank you for your feedback. I honestly was under the impression that strange 10 ways were ajustable for compression and not rebound. You were right that they adjust for rebound, only. This kind of changes my toughts, as these struts are primarily designed for drag racing and you want the weight of the car to transfer to the rear wheels quite rapidly so they can "dig in". Once the rear wheels have enough weight on them, you want that weight to stay somewhat constant for the duration of you run, so you really don't need adjustability in the compression. At least, not as much so as compared to road racing or autoX, where the weight transfer and compression loads shift dynamically throughout the run.

Maybe my best option at this point is to put my old setup back on and introduce rubber bushings back into the equation.

My old setup was: factory bilstiens, H&R SS springs, stock A-arms, UPR K-member, stock upper strut mounts, MM bump steer kit. (I bought camber bolts so I can dial in the alignment without the need for camber adjustability in the CC plates).

I really think having rubber bushings provided the ride quality i have been lacking here on these roads.
 

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
The car is not slammed, it has probably a good 4 fingers width between the tire and fender. The coilover springs are not adjusted all the way down either. I will try to take some pictures later today and post them up. I guess there is a possibility of the spring "popping" out. I mean the noises sounds like something is shaking/rattling around everytime i hit a pothole or bump.
 

2DXTRM

Pushrod 5.0
Established Member
Joined
Sep 17, 2008
Messages
2,422
Location
Some time zone
The car is not slammed, it has probably a good 4 fingers width between the tire and fender. The coilover springs are not adjusted all the way down either. I will try to take some pictures later today and post them up. I guess there is a possibility of the spring "popping" out. I mean the noises sounds like something is shaking/rattling around everytime i hit a pothole or bump.

whats the spring length and spring rate ?

How are the clearances between the coilover sleeve and the strut body? (unless your strut body is threaded).
 

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
Fit between strut body and threaded sleeve was tight, like suction tight. Had to twist it back and fourth to get it all the way down. Spring rates were listed in OP, 250lbs x 12in. Preload was set by jacking up car on control arm till coilover assembly started to pickup the weight of the car, then the strut nut was tightened. I am really just scratching my head right now because i have literally tried all the common fixes to coilover noises.
 

01yellercobra

AKA slo984now
Established Member
Joined
Oct 5, 2005
Messages
21,125
Location
Cali
The car is not slammed, it has probably a good 4 fingers width between the tire and fender. The coilover springs are not adjusted all the way down either. I will try to take some pictures later today and post them up. I guess there is a possibility of the spring "popping" out. I mean the noises sounds like something is shaking/rattling around everytime i hit a pothole or bump.
Do you have small fingers? A 4 finger gap would be huge. I think that would be taller than stock. Maybe you need to back it down a little. When I lift my car and the suspension droops the springs lose all tension. There is usually a clunk when things settle when I lower the car.
 

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
01yellow, i started out with maybe one finger width between fender and wheel and thought my ride hight was too low, so i bumped it up to roughly 3 or 4 to see if that helped. It didn't at all. Can't remember exactly what measurement I took off the top of my head. And I have pretty big hands. Lol
 

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
I just feel like there should be some sort of rubber isolator between either the coil spring and perches or between the perches and CC plates. The design of every 94-04 mustang coilover setup is basically metal touching metal touching metal. For some reason I'm really not surprised it is making so much noise, given the roads here.

I have a 1998 cobra as well with a purely stock suspension and it rides very quite and smooth on the roads here. I know I might be comparing apples to oranges, but the comparison is not a "slight increase in NVH" like Maximum Motorsports suggests with coilovers.
 

01yellercobra

AKA slo984now
Established Member
Joined
Oct 5, 2005
Messages
21,125
Location
Cali
I have the MM coilovers. I occasionally get noise when I'm turning into a driveway or something like that from the spring. I know it's because I never clearanced the tab on the frame enough. Beyond that they're quiet. The ride is decent. At times I wouldn't mind a little stiffer valving in the rear, but that's personal preference.
 

coposrv

Well-Known Member
Established Member
Joined
Sep 4, 2007
Messages
5,030
Location
boston
I had the same set up and literally threw it in the trash. The strange struts were awful. The diameter of the shaft is much smaller than the spherical bearing in the camber plate. I then went to konis and it got better but not much. I ended up back on coil springs and stock I member.

The single worst modification to a 79-04 is a tube k member and coil overs.


Sent from my iPhone using svtperformance.com
 

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
Coposrv, unfortunately I'm glad I'm not the only one who thinks the same way. I just went to the junk yard here and had to buy some used lower control arms to reinstall the stock springs and bilstien struts. I'm going to paint them up and throw them on this weekend.

I bought camber bolts to hopefully get enough adjustment so I won't need CC plates, but don't know how much adjustability the bolts will provide. I will be running H&R SS springs, MM bumpsteer kit, stock bilstiens.

Couple more questions: should I leave the MM CC plates on, or go back to stock strut mounts? I know that I will not be able to get the amount of caster back i had with the camber plates, should this be a significant concern as well, or will I not really notice the difference in stock caster vs. 8° positive i have now?
 

03' White Snake

Well-Known Member
Established Member
Joined
Feb 5, 2007
Messages
3,790
Location
Mass
Coposrv, unfortunately I'm glad I'm not the only one who thinks the same way. I just went to the junk yard here and had to buy some used lower control arms to reinstall the stock springs and bilstien struts. I'm going to paint them up and throw them on this weekend.

I bought camber bolts to hopefully get enough adjustment so I won't need CC plates, but don't know how much adjustability the bolts will provide. I will be running H&R SS springs, MM bumpsteer kit, stock bilstiens.

Couple more questions: should I leave the MM CC plates on, or go back to stock strut mounts? I know that I will not be able to get the amount of caster back i had with the camber plates, should this be a significant concern as well, or will I not really notice the difference in stock caster vs. 8° positive i have now?

Leave the MM CC plates, make sure they are tight and you will have no issues with them. Ran them for years with Tokico D specs and H&R race springs before going to K member and coil overs.

I added poly bump stops onto my struts inside the coil over springs, made my car ride so much better. Keeps everything quiet, but you can tell over big bumps it feels a little floaty because of the stops being squished.
 
Last edited:

03DSGMach1

10's or Bust!
Established Member
Joined
Nov 12, 2006
Messages
1,149
Location
Broward County, Fl
Leave the MM CC plates, makes sure they are tight and you will have no issues with them. Ran them for years with Tokico D specs and H&R race springs before going to K member and coil overs.

I added poly bump stops onto my struts inside the coil over springs, made my car ride so much better. Keeps everything quiet, but you can tell over big bumps it feels a little floaty because of the stops being squished.

Which poly bumpstops did you use if you don’t mind me asking?



Sent from my iPhone using the svtperformance.com mobile app
 

03' White Snake

Well-Known Member
Established Member
Joined
Feb 5, 2007
Messages
3,790
Location
Mass
Which poly bumpstops did you use if you don’t mind me asking?



Sent from my iPhone using the svtperformance.com mobile app

Screenshot_20210222-212618_Gallery.jpg


Mine are prothane. Had them lying around from a bushing kit from years ago. Obv only use the tapered one, not the flat one. https://www.cjponyparts.com/prothan...2tGVDqjWSu0dIpOYZyWW_PBFbcS0Ra0hoCOVgQAvD_BwE

MM makes some too, MM Bumpstop, closed cell foam, pair
 
Last edited:

2003oxfordCobra

New Member
Established Member
Joined
May 31, 2015
Messages
25
Location
Ft. Riley
03WhiteSnake,
When you say to use the tapered one, not the flat one, are you referring to the upper strut mount bushings?

On the stock strut mount, there are two rubber bushings. One on top that is tapered (has a conical washer that is held down by the strut nut), and one on the bottom that is flat (where the strut makes contact with the lower strut mount plate).

I am assuming from your picture that you utilized the upper, tapered, bushing as your bump stop on your coilover kit?
 

Users who are viewing this thread



Top