Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)

Recommended Posts

I posted this over at Rennlist but I thought I would throw it out here to see if I get a different response.

I was getting on the freeway today and as I was accelerating the rear end started to wiggle or shimmy a little bit. I was doing about 80 and the on ramp has a sweeping right hand turn to it. I have felt this a little before but today it was more noticeable. A month ago I lowered the car with H&R's and put 19's on it. The wheels were balanced when I got them and the car has been realigned after the spring install. Any advice would be grateful

A further description would be it started to bounce and wiggle at the same time :drive: :drive: :drive:

Link to comment
Share on other sites

  • Admin

Certainly if you had all four springs done - and chances are they loosened or removed the swaybars for the work. I would go through and make sure everything is where it should be and tight.

One other thing I guess could that happen is if one shock completely died - it might act pretty weird if that happened.

Link to comment
Share on other sites

Certainly if you had all four springs done - and chances are they loosened or removed the swaybars for the work. I would go through and make sure everything is where it should be and tight.

One other thing I guess could that happen is if one shock completely died - it might act pretty weird if that happened.

Thanks Loren! Outside of a shock leaking how can I tell it went bad?

P.S. I have been looking for an excuse to go to a PSS9 setup but I want to cure the problem first

Link to comment
Share on other sites

Landlwilson,

You received several good hints on Rennlist and Renntech. I'm curious what you've eliminated? Have you had the car in the air and checked your tie rods (my guess), wheel bearings, ball joints, swaybars, etc.?

The problem you describe could just be your springs, dampers, sways, tires, etc. not working well together of it could be something like tie rods or ball joints that should be fixed ASAP for safety.

Jim

Link to comment
Share on other sites

A further description would be it started to bounce and wiggle at the same time

I had exactly this same issue after lowering with PSS9s. While in a sweeper at high speed if I hit uneven pavement the car would start to bounce in response to the pavement and once unsettled would feel like it was wiggling in the rear. It was very scary and it felt like I was on the verge of being out of control.

My problem was corrected by changing the damping in the rear to make it stiffer and having the alignment checked and adjusted. There were no loose parts or leaking dampers. My car's ride height is set to X74 specs.

<opinion>

It is my impression is that the 996 ride-height, suspension, wheel, and tire setup from the factory is very well engineered and balanced if not as high performing as some would like. Once you alter that combo you throw things out of balance (and tolerance) to the point that it's noticeable. It's a fine line and don't think it takes much to get out of whack and it takes some work to get it back in line. It ain't a Chevy. Mind you, I'm not chastising -- I changed all of these things myself.

</opinion>

When I was going through this problem there was a guy on 6speedonline with a Turbo who was experiencing the same problem after lowering and he was convinced that the damper was hitting its bump stop and that was causing the wiggle. I called Bilstein and talked with a tech who didn't think this was the cause.

Lowering changes suspension geometry and I had a hard time getting the rear camber set within specs. And... the car is more prone to bump steer. Both the camber change and the tendency to bump steer can unsettle the car in a rough sweeper. The car is much more responsive to steering input but I'm paying a price for that. It requires more concentration and smoothness at speed.

I don't know if any of this helps. A Porsche racing shop near home helped me a lot in sorting out my problems.

Link to comment
Share on other sites

I had a problem with this as well. The problem with my pss9's was that after my corner balance the idiot's lowered the front too much and the springs would fully compress during normal driving creating an under damped rebound problem. The car still is doing some of this albeit not nearly as much at the same settings I had it before the problem. I really wonder if the shocks were damaged/ worn out from the negligence??? I am really thinking about removing them sending them out to bilstein over the break as I am gone for a month snowboarding.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.