BoneStockS4

So I'm thinking about changing spring rates from 700F/800R to something lighter... maybe 500F/600R or 600F/700R. At first it was livable, but after long term exposure to my current bouncy ride I want to try something different. Especially after a ride in LI-S4's car (MTM springs and Eibach shocks I believe). He needs less body roll, but he's got one hell of a daily driver. Anyway, I've finally tweaked my current setup to the point where I think I've finally figured out (from personal experience) just what compression, rebound, and springs actually do. So I'm left thinking that I currently have too much spring for the roads in my area (Long Island).

My reasoning is that the car doesn't soak up imperfections in the road so much as it completely follows them up and down, resulting in a bouncy feeling on anything less than good pavement. At first I had lots of porpoising, but I adjusted that out by going +2.75 turns front and +7 sweeps rear on the rebound. The car felt awesome, but the ride was very HARSH. Based on another AWer suggestion I went to +1.5 turns front rebound, and +5.5 sweeps rear rebound. This reduced the harshness a lot and maintained the front to rear balance, but the bounciness is still there.

So here is my understanding and correct me if I'm wrong! As far as I can tell, springs work with compression dampening of the shock to control how much and how fast the wheel will move up compared to the body. When the wheel hits a bump, the spring will compress and undulate if there is no compression damping. The compression damping acts like a resistor in electronics to dampen out spring undulations in the upward direction (as the wheel travels up). If your spring is too stiff for the compression dampening you will have a compromised ride because the shock cannot prevent the spring from undulating. This is why compression dampening affects ride quality.

Rebound dampening keeps the spring from undulating in the downward direction (wheel moving back towards the ground). I could be wrong, but I believe reducing the rebound dampening allows the spring to push the wheel towards the ground faster. This is what you are doing by adjusting more positive turns (more towards "stiff") on the rebound in a Stasis setup. If you add more rebound dampening (staying towards "soft") the shock fights the spring more and the wheel takes longer to return to the ground. If you adjust this too much the wheel will take too long to come back and the car will "dive" a bit on the far side of a bump. Since Track Sports only have rebound adjustment I know about this from experience.

So to further my goal of smoothing out the ride I think I need to reduce the spring so that the wheel can travel upwards faster with relation to the car body. This way the body won't be pushed up as fast or as forcefully. Hopefully I can then adjust the rebound up more so that the car reacts faster on the other side of bumps, preventing the front from dipping. My big question is this: Is there a danger of having too little spring? I saw a post earlier where someone thought that the VW R32 is "undersprung". For those suspension gurus out there, what are the characteristics of an undersprung ride? Will it feel like you are going to hit the bump stops all the time, or is it something else. I want to make sure that next time I "get it right".

Well, I hope some of this info helps people just don't take any of this as gospel though. It is just my take on suspensions based on reading AW and living with and tweaking a Stasis 600F/700R/touring and 700F/800R/sport setup in my car. Oh, FWIW I didn't mention the 600F/700R/touring setup earlier because I didn't have the rebound adjustment holes and the rebound was set way too low by the original installer. Needless to say it wasn't a great ride and I learned an expensive lesson in that I probably could have made that setup work if I had the rebound adjusment holes. Hindsight is 20/20, c'est la vie. (Heh, I've gone from too soft to too stiff)

So lastly, what are everyone's impressions of Stasis setups with 500F/600R and 600F/700R. Thanks for sticking with this long winded post!

Hal_TT::CBP

They perform well when pushed but cannot dampen the smaller, more subtle actions required for extended street use. I think that if you track occasionally the Stasis setups are a good compromise between the two(they definitely perform well when dialed in correctly). If you are 99% street driven get a dampner that is gas pressurized... you can still run a decent spring(500/600 may be the limits for this style, also depends on compression and rebound dampening valving) and will have better initial control of your suspension.

If you go with a lighter spring setup your high speed ride characteristics likely will improve but the slop that allows the porpoising and bouncing will likely worsen at lower speeds without a change in the valving to compensate for this.

Honestly spend some time with Ryan/Stasis as this is what they are really good at... certainly helped me with my 2 Stasis setups. In the end I guess my car was destined to be primarily a daily driver and not a track queen afterall.

MikekiM@PureMS

<i>They perform well when pushed but cannot dampen the smaller, more subtle actions required for extended street use. </I>

This is precisely what makes KONI a more comfortable shock on the street. A high pressure shock transmits all the road vibrations, small bumps and cracks into the chassis, and doesn't absorb them quite as well as a low pressure shock does.

Ryan tends to agree with me <a href="https://forums.audiworld.com/a4/msgs/1954923.phtml">here</a>

What you gain in comfort, you lose in roll control and transition which really is what you need to perform well on the track.

RKA

Ryan left Stasis. :-(

RKA

still can't work out the right balance for the front to rear rebound, and that bounciness in the front...I've given up on it. It's something I have to live with with the Koni shocks. On a track it does quite well, but the variation in bumps and dips on the street are a real challenge.

BoneStockS4

I agree that the Koni's will never be 100% ideal for the street. Initially I was looking to get a beater and make the S4 more of a weekend and eventually a track carUnfortunately those plans haven't materialized yet and the S4 will be my daily driver for a while yet. This is why I'm going to keep my current springs even if I get lighter ones.

I can live with the Koni compromise between, but 700F/800R is just a little too much for me right now. I am definitely going to talk to Ryan before I do anything, but I just wanted to see what the rest of AW thought.

Thanks again for the feedback! I hope I wasn't too far off with my assumptions of how this stuff works!

BoneStockS4

Now who am I supposed to talk to!?

brian@avalonmotorsports

Give me a call..I downloaded Ryan's brain before he left for Vegas.

moTAP

Have you tried the setup with stock sways instead of the Intrax?

Funkweasel

AND porpoising, I'd say he's pretty spot on. They're just not worth the price. I'd accept the results at maybe $1200, but I'm extremely unhappy with them at the pricepoint they currently sell at.