the flyin' scotsman

I drive fast and hard but its street not 10/10 driving so this is probably why we differ in opinion.

What shock/spring are you looking at?

For what its worth I too have a sense for ride/handling but in a different mode............I roadraced motorcycles for many years proffesionaly, even left some rubber down at SIR.

Ed Hughes

IMO, your not going to find a shock/spring package "off the shelf" for 10/10 driving in a 928. The upgrade kits are offered to what most in the market would want, a "sportier" ride and performance on the street.

I'd say this is true for most any car of today, if you want to go 10/10, you'll need to do some research and go for less mainstream products.

Bill Ball

I found the same "bouncy" ride with Bilstein/Eibachs. I would call it "jiggly" over minor road irregularities and not well controlled over larger bumps.

Here's something maybe I missed that is important -- the Eibach springs are about 1 1/2" shorter than stock. I could assemble the coilovers without a spring compressor - and that is with the ride height adjuster at the halfway point! [Edit: That was rears only. The front srpings need about 1" of compression to install.] What this means is there is very little spring compression preload other than from the weight of the car. I suppose that was a design feature to provide a comfortable ride around town, using the progressive part of the spring, but in my car the ride was "jiggly", nervous and annoying - anything but comfortable. On top of that, large bumps were not controlled.

EDIT: I just removed a bunch of stuff I wrote about Bilsteins and Konis and sport springs because it looks like I don't have sport springs and never did. I may not be the only one confused by the spring options on the S4s. My car has option 474, which is sport shocks. I thought the springs were also upgraded from stock, but I can't find a clear statement about that. There is an option code 637 for sport group, but I gather that is Club Sport or GT suspension. I don't have that option.

Tommy928

I think Bill has described more accurately than I have on "bouncy". The Bilsteins reminded me of the KYB shocks I owned back in the 70's; inadequate control over the initial 1/4" to 1/2" wheel movement causing a nervous, bouncing sensation on small road irregularities - this may be a characteristic of monotube shocks. The Bilsteins also has trouble controlling large bumps and road dips which led me to believe the rebound valving is too soft for the 580 lb/in of the front springs.

cfc928gt

I have weltmeister springs with Konis on the front and Bilsteins on the rear. The Bilstiens are much firmer on the compression stroke. The Konis are soft on compression and adjustable for rebound, I have them set about 85% firm. I found having a bit more give on the front to absorb the initial bump that the Konis provide while having the back end more firm a perfect setup for me. It's amazing to go over one of those 3 mph speedbumps, the really abrupt ones. The front is soft on hitting it and firm on rebound, very controlled, whereas the rear is just a bam, more of a jolt.

the flyin' scotsman

Interesting analysis Bill.........you've gone where I want to go by using a OEM spring with the Bilsteins. Did you have to go back to the OEM collars? any other tricks?

Unless winter lasts way too long it will be a next year project.

Bill Ball

No tricks, at least on the rear. The Bilsteins are threaded, so you use their adjuster. Everything else is the stock parts. Again, these are sport springs. I'm not sure how the Bilsteins would feel with standard springs. [Edit: Turns out I have standard springs, adn the Bilsteins feel fine with them. Firm but still good ride quality] I have not swapped the fronts yet. I'm running sport springs [Edit - No, I have standard springs after all] and Boge reds up there for the moment, but I plan to swap in the Bilsteins and my stock springs. The fronts have different lowerplate as well as adjuster ring.

The day before yesterday we installed a brand new set of Boge reds with sport springs (2 brown stripes on front, 2 blue on rear set) on Matt's 88. [EDIT: These are not sport springs after all] The comparison to the Bilsteins was very instructive. On the fender test, the Bilsteins are MUCH firmer. I can barely push the fender down. In contrast the Boge's are easy to bounce and you get a complete bounce (down, up, a smidge back down). However, when we took the cars for a ride on a test loop with all kinds of road surfaces and some good twisties, if I had been blindfolded I could not have told you which car was which. We were worried that the Boge's were underdamped, but they handled just fine. No wallowing in the corners, no odd bump responses, and suprisingly not all that cushy on the boulevard. Now, it is true I have Boge reds on the front, but we paid attention to the rear end response to some pretty good mid-twisty bumps with my new Bilsteins versus his Boge reds, and both cars felt very controlled.

Just goes to show you that the fender test, with a hundred or so pounds of hand pressure applied at a slow speed, is not very useful unless you looking for a totally dead shock. The Boge reds seem good to me. Track guys may find any of the shocks inadequate, but I always liked my original Boge reds in the twisties.

the flyin' scotsman

Are the sport springs not marked 'orange'?

My OEM springs are brown stripes up front and blue in the rear with no M637 option.

Bill Ball

Malcolm:

I can't recall how the markings work, but both cars I have seen with sport suspension had the browns up front and blues in the rear.

EDIT: OK. I'm a total dumkoff. I have been working all this time under some misconceptions about the springs. I have option 474 which is listed as sport shocks (Boge red originally). So, I probably have stock S4 springs. Some people tried to correct me about the spring markings, but others also piped in with contrary information supporting my notion that I had sport springs. I wonder why the Konis were so bad on my car.

the flyin' scotsman

No worries Bill; thats why we're all here.

PET confirms orange stripes as the sport spring M637 option. Now that you have Bilsteins with your stock springs (brown stripe F blue stripe R) your comments are more valuable to me. Looking forward to your update when you've Bilsteins on all 4 corners with stock springs.

Shane

Let me throw this out there:

What about getting either taller adjusters for the bilsteins or adding a 1"+ spacer between the adjuster and the spring saddle?

This would allow you to get stock ride height and preload the spring some more, to help with the bouncy?!?!

Bill Ball

Shane: I wondered about that. When you buy the package, there are no particular instructions about adjusting ride height considering the shorter springs. I haven't seen spacers mentioned in reference to the Eibach's before. I was planning on calling Jim up this week.

Shane

I wanted mine at 180 in the front, as I wasn't too happy with the lower ride height and having a gravel driveway. Now that I have a new front spoiler, I'm looking at doing this to try and save it from damage.

To get 160 I was also at the very end of the threaded portion on the adjusters.

Bill Ball

Sorry, Shane I re-edited my message for clarity and left out the ride height. In the rear I had no problem getting the ride height to 160+ with the adjuster mid-way. The fronts were in the 150s midway. Maybe I should have dialed everything higher. I just didn't think through the short spring length and no one made any comments about its effect as far as I can recall.

Silver79

I assembled the fronts today and it was impossible to get them together without a spring compressor no matter where the adjuster was. They were assembled following the WSM. Anybody else able to assemble thiers without a spring compressor? The car is an 82 and I believe it had the sport package--front and rear spoilers, bolstered seats, limited slip, and from what I can tell originally came with Bilsteins. I remember there only being a few posts on here before about this package. Somebody can correct me if I'm wrong. Joe