OP brings up an interesting topic. I currently run OE shocks with H&R Springs which is definitely a SURPRISINGLY well tuned setup, and definitely under-valued. I plan to track sometime soon to see what laptimes this setup will do.

The US version OE 996TT shock/spring setup, has a HIGH ride height. A starting point would really be EU spec springs at the least. In my case, the H&R is probably some 1/8" too low, but nevertheless, some testing inputs:

Compared to Bilstein PSS9, the OE shocks w H&R springs are MUCH better for both comfort and handling than PSS9. The main reason is: PSS9 has a completely stupid valving setup for compression and rebound. PSS9 rebound is way too soft to function on track, and the relationship between compression and rebound makes this coilover impossible to dial in well with any modern standards for either track or good street comfort with acceptable chassis control (except after re-valving).

The OE shocks are configured in a way which is used by most prominent sporty car manufacturers, with a quite firm rebound, but with a fairly compliant compression, this makes the car stay in good control even in hard driving cases, yet swallows most rough road bumps and harhness. This is the way a good 2-way coilover can be setup manually to be very fast on track, yet decently comfortable on street, even when using firm springs.

Swaybars:
The H&R spring rates are designed in such a way, that the balance is perfectly neutral even with stock swaybars for spirited street/canyon driving.

For adjustment / track usage, I'm using Eibach Racing adjustable swaybars front/rear (similar to GMG bars which have 1 more adjustment hole and are painted blue instead of red). Adjustment ranges are really relevant and fitment is perfect.

OE shocks vs PSS9 or 2-way: No difference. Coilovers and swaybars don't need eachother to make a difference.

Alignment:
The OE alignment is only good for communte, as mentioned by above poster re DOT requirements ("fishhook" turn tests). Drivingwise, mainly front camber is very straight up, meant to avoid "steering wheel pull" due to grooves in the road caused by roadwear/trucks. With some 1,5 degree negative camber the front end becomes much more controlled with no big downsides on straightline behavior. Close to this number should be attainable with the concentric adjustment of the lower control arm.

3mm toe in rear helps traction.
0mm front makes for responsive steering (going to toe out 1mm COULD give some unwanted nervousness in daily driving, but good specifically for twisty tracks or street tires with long response time when turning in).

DIFF
For LSD... I've been happy with Carbonetic but there are many other brands and types. With engine tuning I would do it even in 4WD mode. With OE power and 4WD it's not crucial for good handling.

Those were some quick thoughts in the no-coil-over discussion.

 

It was standard on the 2004 40th Anniversary C2 and an option on the 99 C2.

 

Great input! You mention of alignment brings up a very interesting question. How many people play with alignment settings before spending $2500+ on a set of coilovers? My guess is not many. If so, how many have experimented enough to find the optimum setup with stock suspension components? So if a change in camber and toe are $100 and make so much difference, why are their more posts here on which coilover setups are best? I intend on getting a suspension before I bolt on any chassis or suspension parts and start there.

It is quite easy to jump on the "lower the ride height the better" band wagon, but their is soo much more to chassis and suspension tuning. I think that fixing the alignment and adding sway bars will fix more than some people realize. I have had rides in cars with the middle of the road coilovers and overall I don't think the warm fuzzy factor is there for me on these setups. I am hoping that if enough info is shared here on this topic it will help others from feeling obligated to spend big money on mediocre coilover setups. This isn't to say that an upgraded coilover setup doesn't have it's place. I just think the stock suspension is often bad mouthed when it is the geometry and sway bars that need the attention to achieve what most people are doing with these cars.

 

You are incorrect. The x73 suspension is not the ROW kit. The X73 suspension lowers your US spec car 40mm (1.6") in the front and 30mm (1.2") in the rear. It lowers the ROW cars 20mm all around. This is much more than just a "few MM".

 

To the OP, what are you trying to achieve with your questions? You haven't mentioned what the intended purpose of your vehicle is.

Is it a:

• DD than needs to comfortable and quiet
• A canyon carver for the weekends on smooth roads
• An fast A to B car on the highway
• A part time track car
• A full time track car

The potential combinations are endless.....

Every suspension system is some form of compromise, as are the alignment settings etc. Sharp turn in from a little toe out is going to increase tire wear. Good high speed mid corner grip will require more negative camber, again with more inside tire wear when on the highway.

Before anyone can give you good advise or give direction we need to know what you want from the car and the conditions you drive it on. What are you willing to give up, what is a must have.

More questions than answers at this point...

 

My objective with this post and these questions are to further the understanding for me and everyone else here of the shortcomings of the stock suspension and handling on the 996TT as well as some other effective solutions. This isn't intended as a "help me choose the right coilover and sway bar" post. I know that coilovers will improve this car in many ways but I have yet to read about anyone pushing the limits of the stock dampers by varying the alignment and sway bars. Until we know the limits of the stock dampers how can anyone make a logical decision on how far they want to take the suspension upgrades?

Under normal circumstances you would decide which suspension upgrades you are going to go with based on your intended use as you mentioned. Then you write the check. I just want a good technical discussion on stock suspension setups that in the end will be of good help to me and others looking to retain stock dampers and springs. So from my angle I am looking to identify and discuss the stock suspension limitations seeing they have not really been clearly defined or discussed previously.

 

I am not suggesting Coil Overs, didn't mention them once in the post.
However the title of your thread is "The ultimate suspension/steering and handling setup with stock dampers..." All I am asking is "The Ultimate for What?"

The ultimate for DD, Track, Canyon Carving. This is always the starting point, what do you want to achieve with your car. Then discussion can talk about Alignment Swaybars etc.

With out an end goal, you are going to have the die hard track guys suggest Coil Overs and the DD Guys say stay the same..... With an end goal then we can discuss the limitations, it becomes easier to define.

 

They fall in with the very few.

 

All of thew above. I think that building a stricly anything other than daily driver isn't going to happen with stock dampers. But I do think you can make a 996TT perform well on a track with stock dampers/springs and other upgrades and improvements and not beat you up for your daily driver duties. The "ultimate" is intended to be in reference to the thread topic not the ultimate suspension setup. I guess I should have clarified that in the title better :/

 

The stock suspension is too soft for decent track performance, antisway bars are not a solution for this, although they will allow reducing the understeering. While they may allow reduction in side to side roll it does nothing for forward and rearward movements which are properly controlled with stiffer springs.

Place to really start is to replace the lower control arm thrust bushings with polyurethane versions, as well as the stock rear toe links inner mount. This shouldnt add much harshness but will allow more precision and less alignment changes under load.

Lots of factors, tires being a large part as the more grip the more the suspension load.

High quality coilovers actually ride very well, id even argue better then stock when correctly adjusted.

 

Could this lsd be retrofitted in a 996tt?

 

Do OEM GT2 shocks/struts bolt in?

 

I will not argue that the coilovers will eliminate the body roll encountered on the track. But the main issues with comfort on an aftermarket coilover setup comes from ride height IMHO. Do these coilover setups allow for proper dampening at stock ride height? Remember, this car is driven more on the road than track so is the handicap of ride height worth it for 3-5 DEs a year? For me the answer is no. One of the main points I am trying to make is does it make any sense to put a race car suspension on a car if you are not racing every weekend competitively? Especially if the people driving the car don't know how to adjust the coilovers to achieve their goals in handling? Their is no doubt that the stock suspension is not good for a race car or a competitive weekend track setup, but it isn't useless. I will just have to tweak my car with the stock dampers and see for myself I think.

 

Cheapo OEM suspension.
$500 - Porscche ROW springs. Stifffer and 1/2"(?) lower. (been there)
$150 - GT3 5 way adjustible rear sway bar. (still there)
$???? - R888 Racing compound tires.

All stock and cheap. It won't begin to keep you from wanting MOTONS though.

 

What improvements did it make? I do have a powerful lust for Motons but it is just not an option for me. I have no intentions on trying to make the stock suspension handle like motons. Just better than stock. I think that I could use a stock suspension setup on the track with a good alignment and sway bars and the car not do better than many cars still. After all I am not trying to win a lemans with this setup. Just have some fun. A 1/2" drop is manageable IMHO. Still have the ROW springs? Did the stock dampers dampen enough with these springs?