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DPP528 01-14-2013 07:12 PM

Suspension Question Koni FSD
So here's what I'm thinking... at 105k (bone stock) miles I've gotten my money's worth out of the shocks, so I'm thinking about upgrading.

Stock 03/00 Sport Suspension to my knowledge is made by Boge, which is now owned by Sachs- I want to upgrade if possible without compromising ride quality. The car sits on OEM sport 17" style 5 rims.

Bilstien's are really not an option for me, from what I hear they're much harder than stock.

I'm looking into Koni FSD, Does anyone have any experience with these shocks? How do they compare with the stock sport suspension?

Further, does anyone have both Koni FSD's and the Eibach spring kit? I'm curious if it's worth swapping the stock springs out for the Eibachs. My car is sitting pretty low as it is due to the worn suspension, but are the Eibach springs really that much lower? Do they negatively affect the ride quality?

I have a feeling that the FSD's and the Eibach springs will actually make my car sit higher than it currently is. Right now it's nearly impossible to go over a speed bump without bottoming out, and putting the car on a lift involves lots of floorjack finessing due to the low stance.

Here's another picture so you all can get a look at the current ride height;


JimLev 01-14-2013 08:21 PM

I installed FSD's and H&R 50464 springs in my '00 540 about 6 years ago. I love them, no problems, got ~60K on them now.
The H&R's drop the car just enough to suit me.
The FSD's won't lift the car, the springs control ride height with these struts/shocks.

Fudman 01-15-2013 04:37 AM

Do a search on this forum for FSDs. I recall there were some durability issues raised on this forum regarding FSDs on the I6 (when I was looking at replacement struts). They were a great replacement except for the durability.

DPP528 01-16-2013 09:43 AM

As it seems right now the stock Boge is the way to go for longevity, performance and ride comfort. I am aware of the reliability issues; what would be your (anyone's) recommendation for upgrading the shocks?

matt540 01-16-2013 10:14 AM

I went with the Koni and the Eibach setup and I'm happy with the ride.

Fudman 01-16-2013 10:48 AM

Asking for another's opinion on shock performance is tough because ride quality (as opposed to handling) is quite subjective. There are tradeoffs in any shock selection. However, the question on shock selection is further complicated by the risk for problems and your tolerance for risk. This summarizes the big 3 shock options. Search for more details. Also keep in mind that these shocks will feel different depending if you have sport or comfort seats.

The Boge sport's represent a good combination of performance and ride quality. They are the lowest cost option and have a reasonable lifespan with no known reliability issues.

The Koni yellows represent a good combination of improved performance, excellent lifespan and with a slight reduction in ride quality but at a higher cost.

The Koni FSD's represent a good combination of improved performance with good ride quality but at higher cost and with some risk for a shortened lifespan (search for details).

Bilstein HD's represent a combination of improved performance, exceptional lifespan with some reduction in ride quality but at a higher cost and with some risk for problems (search clunking).

Bilstein Sports give greatly improved performance with exceptional lifespan but with a even bigger reduction in ride quality at a higher cost.

I personally stayed with Boge's because ride quality was most important and my concerns with some of the problems associated with HDs and FSDs. Skip the springs since you are already a bit lower than stock. A shorter spring will need to be a stiffer spring in order to avoid bottoming out due to the shorter travel length so the ride quality will be noticeably degraded. If you simply want to improve handling, get an M5 rear sway bar and you will get flatter cornering with no compromise in ride quality.

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