[jmeas]

i've been searching everywhere, across audi/bimmer forums. I picked up some sport springs a while ago, then i recently bought the FSDs from a member on here.

i thought that these would pair perfectly fine together. but i'm reading multiple places w people stating this will not work, and at the same time, others say it will work. looking for a definite answer to figure out if i screwed myself or not.

many people say the FSDs pair with the Eibach Pro kit springs, but to my understanding, the Eibach and HR Sports provide almost the same drop.

hopefully i can get some clarification

[smack]

You can use the FSD's with your sports without a problem. There are quite a few people on here than run that setup.

[cssnms]

It has little to do with the difference in drop between the two springs and everything to do with the spring rates. The H&R's have a higher spring rate than the Eibach Pro Kit, or in other words the H&R's are stiffer.

The Koni FSD shocks are more of a zsp OEM replacement vs say the Koni Yellows that are adjustable and more suited to be paired with the higher spring rate of the H&R sports. You can certainly run your set up and the side effects may not bother you or it may over time and you will want to replace either your shocks or springs.

[jmeas]

thanks for the input guys..

what kind of "side effects" would i see? bad ride quality? bottoming out or anything that would cause underbody damage? or would it just wear the fsd's out faster?

[cssnms]

Originally Posted by jmeas

thanks for the input guys..

what kind of "side effects" would i see? bad ride quality? bottoming out or anything that would cause underbody damage? or would it just wear the fsd's out faster?

When shocks cannot handle higher spring rates although subject to interprutaion the ride can be jittery, bouncy and overall not very composed. It will compromise your cars handling. Again none of this may bother you, but then again why risk it?

Why not consider selling the springs and put that money towards springs that are better matched for the shocks or vice versa? Does your car currently have ZSP? If so, sell your dampers and springs and buy Eibach Pro Kit springs, they should match well with your zsp dampers.

[jmeas]

dang, wasn't the news i wanted to hear but good to know. i definitely dont want a jittery, harsh ride, which is why went with the FSDs. now time to find some Eibachs

[HighlandPete]

Coincidence that this topic is in discussion today, as I've been re-reading some of the data on the Koni FSD, for the other thread on tire pressure.

Starting from the belief and marketing comments that the Koni FSD is valved around the OEM spring rates and setup, we are pushing the envelope with much higher spring rates.

From my understanding, the higher spring rate will be increasing the suspension frequency and that means, in the case off the FSD, the high frequency valving will be open more of the time. That doesn't translate too well with a stiff spring set up. Makes it underdamped in some situations, not matched at all, as I see it. I can see why the Eibach spring is more suited, it is the progessive spring rate that I believe helps the FSD to keep in the proper working range.

HighlandPete

[jmeas]

dang. now to sell someone a fresh set of FSDs and grab some yellows

[jwong77]

Originally Posted by HighlandPete

Coincidence that this topic is in discussion today, as I've been re-reading some of the data on the Koni FSD, for the other thread on tire pressure.

Starting from the belief and marketing comments that the Koni FSD is valved around the OEM spring rates and setup, we are pushing the envelope with much higher spring rates.

From my understanding, the higher spring rate will be increasing the suspension frequency and that means, in the case off the FSD, the high frequency valving will be open more of the time. That doesn't translate too well with a stiff spring set up. Makes it underdamped in some situations, not matched at all, as I see it. I can see why the Eibach spring is more suited, it is the progessive spring rate that I believe helps the FSD to keep in the proper working range.

HighlandPete

Thanks HighlandPete, but I don't quite follow your logic. Wouldn't the suspension frequency of the stock suspension still cause the FSD to be in the range where the high frequency valving is open anyway? My understanding about the operation of the FSD, is that that unless the suspension frequency was very low (ie. in the case of hard cornering), then the high frequency valve would stay open in normal cases?