Hey guys, I need a little help.

I recently swapped out my '06 MCS sport springs for the H-Sport spring and rear sway bar. All my researches pointed to this being a better ride quality, better performance springs than the OEM sport package springs. Well, they do feel better BUT now the rear feels REALLY jumpy. The front of the car feels fairly well planted but the rear would bounce up over ever slight road bump. I recall reading here in the past that someone suggested doing some kind of rear end adjustment for this very same issue but I was not able to find the thread. Any information would be greatly appreciated.

Jerry

 

your rear dampers are shot. get some FSD's.

 

My car is only 6 months old. I doubt that the dampers are gone. I vaguely recall that the old thread mentioned something about needing to be "unloaded" on an alignment lift. I did not comprehend what that was all about .

By "jumpy" I meant the rear has a tendency to "kick up".

 

ok, did you put vehicle load when you tightened everything down?

 

did you remeber to use the bumpstops that came with the springs and not the stockers?

 

No. Car was jacked up at all four points.

Yes, I did use the bump stops that came with the springs.

 

get a rear end alignment, if the rear feels like its shooting left or right when you hit bumps, then your toe is out in the rear

 

You mean it kicks up after a bump? Sounds like the damper is shot and isn't giving enough rebound control to me...

 

I had exactly the same problem and my car had only 2,000 miles. The addition of the Koni FSDs changed the ride dramatically.

 

are the springs broken in yet? what setting is the rear sway set at?

don't get into buying a new set of struts yet...
1. let the springs settle first.
2. set the sway to the softest or the middle setting.
3. check your toe (alignment...)

see if the ride quiets down a bit. you have to understand you basically threw down a lot of suspension changes to your car in one shot so let the car settle and let your driving style adjust to the way the car handles.

take it one step at a time, don't keep buying stuff to fix other things when you don't even know what the problem is yet. slow your roll, you'll be ok.

good luck

 

+1

Money does not mean Fix!

 

+2

 

If you notice it especially on uneven surfaces, I'd guess it may be the toe and certainly the increased camber. The dramatically increased camber that results from lowering springs can cause the car to feel a bit unsettled for some driver/car combinations.

The way to fix that to your tastes is adjusting the rear control arms.

A good alignment shop can tell you where you are with rear camber and toe.

I've done this with two MINIs that were fairly modified.

 

Thanks for all your inputs. I do want to get to the cause of this issue and address it accordingly. Koni FSD is great stuff but I also believe OEM dampers and H-Sport springs will also make a very competent setup. I will go to my local alignment shop and have them look it over. Will get back to you guys on the finding.

Right now my suspension setting is;
OEM dampers, H-Sport Springs (1" lowered) and H-Sport Competition Rear Sway Bar (mid setting)

Overall, cornering is way superior than the original OEM sport package. The jumpy rear is my only issue now. Does anyone have the same setup yet better result?

 

I have a very similar setup and all is well. I've been running H Sport springs on my car for a year now and over 10k miles with a Alta 22mm Rear sway. No jump rear and I think the ride is more comfortable then with stock springs. Although the ride got much better once I swapped out for non-runflat tires.

 

I have H-Sports on OEM SS shocks with alta rear sway on stiffest, with helix rear control arms. no problems at all with this combo, drives very nicely. i'm taking it in for an alignment this weekend, but its drove very smoothly so far.

i'm 90% sure your problem is rear toe, not anything to do with your shocks.

 

When you put the spring on did you also put lower control arms on? Look at the rear wheels from behind the car. Do the wheels look like this / \? Or like this | |. If the wheels look like the former then you need to add lower control arms on the rear. If you dont you will wear out a set of tires on the rear in very short order. Once I put rear control arms on mine(Eibach Camber Kit) the rear wheels stood up like they are supposed to and the car handled much much better.

Jack

 

not to contradict you jack but more camber will handle better in the turns. wear in the rear is not as severe as it sounds... i was running with -3.5 in the rears for 8000 miles because i couldnt afford control arms.

im not sure what years this statement applies to but the rears are adjustable a little... not much but a little. something like 2 degrees. not exactly sure.

my setup was the h+r's w/ stock struts and hsport comp sway in the middle. 16" non runflats. started out bouncy but setttled down after 5-600 miles.

 

In the front, yes, negative camber will help... In the rear, it will contribute to understeer, as the rear will grip better than the front...

 

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