Ok so I FINALLY got some time since purchasing my pcar to take a long drive and see what she could do.
Car was a joy to drive, except when I got up to 90+ mph. (If there are any SoCal law enforcement folks here...I was only going 65, honest! )

Car got very floaty and hitting the 45mph freeway onramp sweepers at speeds I would normally take them at in my Dinan 330i (80-90mph) was less than confidence inspiring (to put it mildly).
Even at lower speeds, any sort of dip or road imperfection in a corner had my car washing around like a stock ricer and me muscling the wheel to keep her in check. I was surprised to say the least, since I figured the OEM suspension would be a bit more capable.

What do you all suggest to eliminate this problem while not adding too much harshness to the ride?
Will a set of progressive springs / shocks (HR + Bilstein, PSS9, etc) do the trick or will I also need to consider other component changes?

 

ROW 030 will solve your problems.... includes shocks and new sway bars and all mounting gear... X74 is also good... much lower than R0W 030 but more $$$... both kits are porsche OEM.

 

PSS9s will do it without ANY additional harshness...while lowering the car as well.....best mod I have done...

 

Thanks guys- Something will in fact be done about this...soon.

 

I my opinion the stock suspension is crap. I'm glad to hear you agree. There are a lot of options for the 996. Do some research here or at forums.rennlist.com and pic the best one for you.

I went the x74 route and couldn't be happier. Let me know if you have any questions about it.

 

Seems like even the OEM suspension should be doing much better than described. That said, I really like my PSS9.

 

pss9's was the first thing I did.

 

Wow this makes no sense, are you sure every thing is in working order? I took my 99 C4 to the track for the first time this weekend bone stock suspenion. I have leaking rear struts and cheap tires on and the car ripped! I was thrilled at its handling. Far better than the driver. I was doing high speed corners from 55 mph up to 90mph. I also took the car to 155 on a straight section of high way as well on Friday was great.

That said due to the leaky struts I am putting on PSS9 this month!

 

mountain- yeah everything checks out ok- my pcar has 29k miles on it, could it be that the stock shocks are worn out? That is the overall feeling at high speeds.
I'm sure your C4 suspension and handling is quite different that a C2, nevertheless I was surprised at how washy it felt.

 

Maybe a lame question, isn't there an OEM Mo30 kit as well and if so what is it?
Is ROW 030 lower than the stock setup?

 

If you're not sure you are going to frequently track it, have the OEM supension checked out before you jump to PSS9, etc. It will give you a stiffer ride that you might not like on your streets. I love it stiff, while my wife doesn't.

 

thanks- not going to be doing much tracking with my tiptronic...

Looking for a good tradeoff between added performance and decent street ride (in LA, the streets just suck)

 

My shocks are original and shot, both rears are leaking and have 43k on them. We have also coverd the issue lateley about the aero kit and I see you don't have one. My car has a full aero kit and I am sure that helps at high speeds. I will be putting on the Pss9 set up in a few weeks so I will let you know.

 

PSS9 is your answer then...

 

My stock shocks had 29K on them when I pulled them off. No leaks, working as they should and they sucked. The stock shocks are manufactured by Boge.

The ride you are describing in your original post is exactly what my car rode like until I swapped out the suspension. (float, body roll, harsh, noisey)

I guess suspension quality is all relative. It depends on what you came from . I had been driving a S2000 for the previous 5 years and it was head and shoulders above the stock carrera suspension.

The difference between M030 and ROW M030 is simply ride height. The ROW sits ~10mm lower.

We get into this arguement here all the time, but I will just state my opinion. The PSS9 is a great system, but for your interest I think it is overkill. Yes they are adjustible, but it doesn't sound like you are going to be doing any tracking. The PSS9 will cost about $2000 plus install with ride height, and corner balancing and you still don't have swaybars with it. The ROW M030 kit comes with new springs, shocks, swaybars and bushings for ~$1100. Installation does not require corner balancing. The trade off is that it is not adjustible. But seriously how often are you going to pull out your subwoofer and pull up the carpet to get to the rear adjusters? Or pull out your torx driver set to remove the plastic covers over your front struts to adjust the them?

All a matter of personal preference I supose. Whatever route you choose you will be amazed how your Porsche will be transformed by changing the suspension. It is possible to get superior handling without sacraficing ride quality.