I posted a thread about a rear sway bar upgrade and the subject prompted me to look further into past threads on how to tune the 996TT's handling using stock dampers. Most people who desire better handling on the 996TT just buy coilovers. The 996TT was a well though out sports car and the suspension is far more capable than most people credit it for. Sure the 996TT understeers and can plow in turns, but this is a common occurance in all AWD cars especially in America where the DOT requirements here require limp wristed steering/handling setups. Most people automatically assume that the suspension is crap and should be replaced. But consider that the 996TT is a pretty comfortable ride for a sports car that has the capabilities that the 996TT has. This is a difficult to achieve goal anyway you look at it. So the question I have is have we squeezed the most out of these dampers and other suspension components?

Swaybars
Nearly every car in the USA has been tainted by our DOT's safety requirements. Even the sway bars. I am reluctant to change my suspension because I believe that just lowering the car is not any help. And to get a suspension that gives more than adjustable ride height would cost alot of money and compromise the daily driving experience. So what sway bar setup would fix some of the understeer issues this car has stock? Rear sway only or front and rear? Are adjustable sway links needed on stock ride height? Which bar setup?

Alignment
It is no mystery that the stock 996TT alignment specs do not help in the handling department. Probably another limp wristed solution the US DOT had for the 996TT's ability to scare people. So that being said what are the alignment specs or solutions for cars retaining a stock damper setup? Can these goal be reached without toe and camber kits?

LSD
Not the drug invented by Timothy Leary, the acronym for limited slip differential. Their are multiple types of LSDs and if you are retaining the stock AWD system you cannot use any of them. Some are better suited for you based on intended use. Our car in stock setup has an open differential which means that in tight corners when the inner tire has the tendancy to lift the outer tire will loose torque and the car will loose it's ability to pull through the turn without dumping speed. The LSD is intended to fix this and can completely transform the car's ability to negotiate turns. So what setup is the right setup for a stock car? What setup has more time between rebuilds and maintenance?

In summary I am hoping for people that know the answers to these questions more than I do can contribute in a completely objective manner to help people like me that want the 996TT be a great setup without spending 10k in upgraded coilovers and various links and control arms. And maybe somebody in the process can also teach me how to not write a run-on sentance. Let's try to keep this discussion as objective as possible and provide some good data and try to not turn this into a vendor plug/war. I am hoping that this thread can be a good source for info and understanding that will be linked in the knowledge sub-forum. Oh and I DON"T WANT COILOVERS!!!!!!

 

So, you are not looking to lower your car at all? Simply stick with the stock ride height?

 

adam from houston here put on GMG sways and i think eibach or H&r springs and it made a world of difference and then franks car with JIC's wasnt much better honestly.

 

I am also considering going with just sways and links as I also do not want to lower the car.

 

Rear GT2 bar, rear toe links and adj GT3 front lower control arms. This setup uses almost all Porsche parts and will get you all the camber you want.

 

My father has bilstein coilovers on his TT and personally I think its more comfortable.

 

alignment is critical over anything.. some toe out in the front and toe in on the rear makes a world of difference. understeer is practically irradiated.. yes thats with a turbo!

i would advise against lowering springs, yes they give the car a lowered stance but to be honest the ride gets very harsh on some roads..

i have come to realize after driving a few turbos and a gt2 with various setups that you need to make a critical decision. Go BIG and i mean BIG or settle with a simple setup like the PSS10's if you just want to improve ride quality and lower the car slightly. Note that the pss10's cannot achieve gt2 ride height without compromising the dampening.

the bilsteins will offer greatly improved dampening over the stock setup and do actually reduce body roll quite considerably.

i have had pss9's in a previous car, the main issue i had with them was when i wanted to get more aggressive handling/accurate i would stiffen up the shocks. The springs that come with the bilsteins are simply undersprung.. so you have to counter that with the shock.. which is a no no..

yes you could opt to change out the springs to a stiffer rate and have the coilovers revalved but then its not really a pss10 anymore and your getting into JRZ RS money.

Bottom line is that if you go BIG i.e JRZ or Moton there are many other components necessary to get them to function correctly!

For Example

Solid Top Mounts
Toe Links
Drop links Front and Rear
Adjustable Control Arms front and rear if you want ultimate adjustability
Sway Bar for the rear - preferably hollow
Dog Bones
Coilovers/springs/tender springs

if you go with the pss10's you don't need all these parts so you will be in for a lot less.
i go back and forth on what would be best for me, being that the car is only driven aggressively on twisty roads and will probably see the track 3-4 times a year.

what i can say though is there is a world of difference between the quality of dampening between the JRZ/Motons's compared to PSS10's

im no expert nor claim to be - im just trying to offer up my thoughts

i do sometimes think that i will dump more money into my car in mods than its worth!

can be a scary thought .... Mike

FOR THE RECORD I LOVE AWD!

 

The stock 996 Turbo has an open differential? This really surprises me. So does the car have only a center diff to shift power to the front or back but not side to side? Can someone elaborate?

 

Yes. I like that my car doesn't double as a street sweeper
I like stock components and don't really want to spend the money on the lower end coilovers like the Bilsteins or H&Rs knowing that money I am really not getting what I want. Without the need to lower the car it seems silly to do coilovers unless I go straight for Motons. And I don't want to spend that kind of money.

 

It has a center differential located in the front differential housing to be a torque distributor.

 

Not understanding how or why you commented on not being able to install any LSD if you keep the AWD...makes no sense and isnt true. The big problem IMO with the turbos handling is the lack of a rear LSD. When exiting any corner that will unweight the inside rear tire will allow it to spin, the center diff instantly sences this and transfers power to the front which in my experience creates a front end push that isnt welcome during hard acceleration out of the corner. This would gets worse with antisway bars and stiffer springs.

 

Despite you saying pretty darn clearly you don't want coilovers, half the people still recommended them. Why? Well I know the answer but honestly, I went through the same thing on my old 996 C4 where people recommended against doing just springs but nobody had ever done it and seen how it really worked. And they all proved to be wrong. People tend to recommend the setups they've done before and ignore the real question the OP asks. I won't.

I'm in the same boat, I just want a bit better handling, but I can't lower the car because of a GT2 front end swap with pretty low carbon fiber lip. There's too many places here in CO that I already can't take my 996 Turbo or have trouble getting into or out of parking lots.

From all my research, I arrived at the decision that there's two places to start:
1. H&R or similar sways and new endlinks
2. Better alignment

If you do those two things, you should have a well-improved car.

You could also swap the springs, but you said what's best with stock struts. I guess the question is, are you willing to shorten the lifespan of your stock struts and replace them with aftermarket units later? But then you have to figure that you'll just be paying labor twice and at the end of the day, it's better to replace both springs and struts now. But you said stock struts so I'd just stick with the two things I listed above, then put in new springs and struts whenever your stock struts wear out.

 

Very few Porsche come with a LSD. People can add to the list, but GT2, GT3, both RS versions, cup cars? and GT. I think the old RS America maybe? Most have open diffs.

 

I was advised by Gbox who knows more about transmissions and such than I that to stay with AWD you need to take careful consideration into which LSD to use. I understand the need and purpose of the LSD. It isn't that you can't use LSDs period, just that you have to be mindful of which one you use when you run AWD.

 

Sounds to me like you need the ROW X-73 kit. While ride height is lowered a few MM, it's the standard round the world. I'm sure you could use different sways to tweak it, as well. And to keep from bastardizing you car, they're Porsche tested (and taxed) parts. Some talk about including the x-73 motor mounts for added torsional rigidity.

As you know, I have just the H&R springs and feel that the stock shocks allow for to much rebound. I'm thinking about swapping to a shorter Bilstein shock and a new alignment before I go for the sways. Fortunately for you, you'll be invited to help turn wrenches and laugh at my busted knuckles.