This article was contributed by Bill Gregory who is starting a programme to upgrade his C2 to 964RS suspension specs.  Here is his stage 1 report.  for details of his springs and shocks upgrade click here.

Upgrading to a 964 RS Sway Bar - by Bill Gregory

Many like to upgrade their 964 suspensions to both lower the overall vehicle height and stiffen up the suspension, which can be for street usage, track usage, or some combination of both. I am preparing my 1993 C2, US model, for dual purpose street/track usage, which includes upgrading to the 964 Carrera RS suspension (struts, shocks, coil springs, etc.) The first part, and easiest, of the upgrade is to install the Carrera RS front sway bar.

The Carrera RS bar is a 5 position adjustable 24mm bar, as compared to the stock 20mm non-adjustable standard sway bar on the C2/4 (M030 option was 22mm), and was the standard sway bar installed on the Carrera RS, which was available in several trim levels in Europe, and was not imported into the US (not counting the 45 Cup Cars that were brought into the US for the to-be cancelled racing series).

An important consideration in making the update described below is to ensure whoever makes the updates is qualified and competent to safely complete it. Obviously, since I'm not doing the work, I can't guarantee or take responsibility for the fitness or success of the installation.

Parts Required

First, you'll need to source the parts. They are available through Porsche and other vendors:

 Pictures below show this set of parts with a close-up of just the non-bar parts.

What goes Where

After raising the front end and securing it safely, as you'll be underneath it, remove both front wheels. First look at what you've got. There's a link on the back of the hub that connects to the swaybar, which can be seen here -  it looks like a tie rod end or ball joint.
The bottom of the link is attached to the swaybar, and can be seen arrowed here.

There is a bushing on each side that holds the sway bar to the a-arm, and can be seen behind the flexible brake line.
 

Comparing some of the parts the left hand picture below shows the stock and RS stabilizer links. The RS links are shorter and thicker than stock.  The right hand picture shows the bushings and bushing holder. The original bushings have 2 blue dots and the RS have 2 silver dots. The RS rubber bushings are stamped "Italy" on the reverse side.
 

Removing the Stock Swaybar

First thing to do is to remove the bottom tray that runs between the front wheels. There are maybe 10 plastic nuts and 2 bolts, all with 10mm heads. Next, you'll take out the existing swaybar. Start with the links on each side, using 17mm wrench or socket.  With the links out, next the bushings come out. Use a 13mm wrench or socket on top and a 13mm socket on the bottom. There's only one bolt holding the bushing in. After undoing the bushing, pull both the metal part and the rubber part (which is split on one side) off the swaybar, and wiggle the swaybar out one side or the other. Be careful not to entangle the flexible brake lines when removing the swaybar.

Fitting the New Swaybar

Before you install the new swaybar, look it over. I found that somewhere between Germany and the US that there were some nicks and scratches, nothing major, but still visible in the swaybar finish. You may want to touch up any nicks with paint before installing the bar. I used flat black rust sealing paint, which you'll notice in some of the pictures below (looks like a swaybars version of a bad day shaving).

Feed the swaybar through so it's approximately in position, as shown below.

Next, you'll install the new rubber bushing and bushing holder on each side - note the raised portion on the swaybar is on the inside, facing each other. I use a little silicone grease (not silicone sealer) on the inside of the bushing for lubrication and to aid bushing longevity. The picture below shows the bushing installed with the tab inserted in the lower arm.

Next reinstall the 13mm bolt. Here I found that the bolt wasn't long enough to cinch down the bushing holder, so I used two new grade 8.8 13mm bolts, roughly 1/2" (12mm-13mm) longer, with new lock nuts (with plastic in the end). Next, the side links. Note the part numbers as one is for the left and one for the right. Here you'll reuse the nut to attach the top link, and you'll use the 15mm locking nut to attach the link to the swaybar. Finally, below you can see the new bottom link connection.

Reinstall the plastic under tray, put your wheels back on, and you're done!  Note that you don't need to realign the suspension, as the sway bar installation doesn't affect caster, camber, or toe adjustments.