996 Cab - Reduce Body Roll w/ Sway Bar? Street Use Only

Hi Guys, I'm sure this has been discussed many times, but the more I read, the less consensus I see. I recently purchased a 996 Cabriolet with stock/standard/original suspension at 69k miles. I'll determine soon if indeed need new shocks. I'd like to keep the car as stock as possible, or easy to bolt back on/off items in case I sell. When driving at 70-80 on some tighter freeway curves, there was way more body roll and less grip (brand new 18" summer tires) than I'd like or would have expected. Sway bar is easier to bolt on/off than new springs. Seen people saying to reduce body roll, both saying to get only a bigger Rear, and only to get a bigger front bar. Can y'all weigh in here? This is for spirited street driving only - freeways, canyon carving, never about 8/10th's. Pls advise! Thx so much!

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At 20 years old and 70k miles, I would replace all suspension components that have rubber/plastic in them before considering sway bars.

I got a 99 Cab with 100k miles in Nov. I wanted to refresh suspension to stock. Got Bilstein B4s and replaced droplinks. Added pilot sport 4s tires on 18" twists. It took a fair amount of driving for suspension to settle in. There however is not much "roll" ever. I find in sharp turn (Los Angeles Crest highways) you need to really hammer the throttle to lock the car into the turn. There is an adjustment to rear engine driving, and the rear is a little too happy to come loose when pushing but it takes a lot. You have to load the car up going into the turn with moving weight to the front wheels. You might want to get wide fronts than stock as well. I also thought I wanted "stock" but I kind of wish now I had at least upped the struts to the Sport version, which I think are B6s. From what I read, the beefier sway bars don't really do much. The chassis is pretty darn stiff, even the cabs. You could probably avoid coilovers.

Thanks. I planned on doing that anyway. Got a list? I need to put it up and see if anything has indeed already been replaced. Only thing mechanic last caught and said looked like it should be redone were outer tie rods

Thanks. Was thinking if I redo springs/shocks going with B6's and ROW springs

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That's pretty much what I wished I had known before hand. The ROW springs will bring down the ridic high front end. I had a shop do these: Bilstein B4 (per my request for stock fitment), drop links, bump rubber, rear sway bar links, and upper strut mounts. After I had the work done, the car drove really weird. Combo of new struts that really did need to settle, and comparing new struts to 99k miles struts that had zero dampening... But even though they get good reviews and are a dedicated Porsche shop, and I trusted the short list, I should have pushed to get parts swapped out since everything was disconnected anyway. I have been trying to find how to get ROW springs in there, but it might also require some other parts being swapped. I'll be doing it myself this time around...

You mean, you did B6's with your stock springs? Trying to follow - what was your error?

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I wish I had known about Row parts, and should have done "sport" aka B6. Plus replaced everything else I could have when it was all out.

Gotcha. The M030 stuff has gotten really expensive. That's why I think I'd just have to stick with the springs, and save some back on the cost of B6's vs B4's. I wish i could find a list of all the suspension parts made of plastic/rubber to replace whilst in there. Maybe once that's all done I'd try it out before even bothering to add new sway bars

I have a 99 Cab and have tracked it and drive the car year round on the street and highway. The first thing to have a look at is alignment. Your car will behave a lot differently if it�s setup for a more aggressive stance at the expense of tire wear. A super lame, max tire life setting could yield 20,000 mile or more of tire life versus as little as 5,000 for an aggressive setup. This is all toe and camber I�m talking about. I don�t really notice the body roll as much as chassis flex - the flex I feel is the twisting of the body from side to side on uneven surfaces, and under acceleration. General rule of thumb for sway bars: a bigger/stiffer sway bar at the rear could cause more oversteer than before. A bigger/stiffer sway bar at the front could cause more understeer. So I�d exercise caution because you don�t currently state you have any traction issues. Also play with tire pressures. I run stock pressures, but you might get better feel by dropping a few PSI on all corners.

Unless you plan on tracking the car, you won't really need to upgrade your swaybars unless your oem sway bars are in bad shape. As Mike said, stiffer rears than fronts will help reduce understeer and vice-versa. You won't notice it unless you are on the track at speed and trying to get the car to rotate better. If you want sway bars, then I would recommend Tarret. But if you are going to that extreme then consider a good set of coilovers.

The parts with rubber Front LCA 99634105319 Upper Shock mount 99734301801 Sway bar bushings 99634379212 Rear LCA 99634105319 Upper Control Arm 99733104701 Rear Toe link 99733404504 Shock Mount 99633305903 Sway bar bushing 99633379224 Also engine and transmission mounts are rubber.

You're amazing, HB? Just to ask even more of you...... DO you have part #'s for the engine and tranny mounts? Again, amazing and thanks! Also, my tech had advised me to get new outer tie rods, since the rubber on the ends was worn. Those have rubber, so am I missing other parts? Inner tie rods? etc??

My '04 coupe bought last year with 66k had been very well maintained. New (<10k mile). Bilstein B4s on stock springs. New OEM pads, rotors. At some point it received a strut brace. Although I would have opted for B6s, the B4s are fine for now. I did have what I felt was more body roll than I wanted. (My other Porsche is a 981 with X73 suspension.). Here in the NC mountains, body roll is much more noticeable on our frequent tight , decreasing radius turns. As a first tentative step, I opted for the Eibach sway bar kit with the rear in the mid setting. It made a noticeable difference in roll stiffness. The rubber suspension bits are still in decent shape, but will be changed out when I go to Eibach Sport Springs and likely different shocks.

OP - Welcome! I don’t know what tires (tire mileage) are mounted. You’re concerned about two different observations: body roll and grip. Tire mold release? Summer tire performance varies significantly, tire to tire, at 8/10 for 996. The body roll may be a lot of things. Cab has a little extra weight over the rear axle. 70,000 miles is a good number for a full refresh. Tire sidewall flex, alignment, spring and shock tuning, rake, brake bias, etc, influence chassis cornering dynamics (duh). If this is your first significant seat time in a 996, you’re discovering just how much the car tells you through your hands and butt. Others have pointed you toward getting a new suspension baseline when you have the time and coin to do so. Good words. I think an adjustable rear sway bar is a highly undervalued bit of performance kit. A 3-hole rear bar takes very little time, money, effort to install or adjust. 5-hole is probably overkill for DD. If you put one on right now and went one notch stiffer, you’d likely be able to feel the difference immediately, especially at throttle-on-exit because the outside rear tire will have a bigger, more stable contact patch. But, my experience with 996’s is you have to manage the front end first (understeer sucks!), before you get too involved with rear setup. If your front end isn’t right, that extra rear grip will cause understeer. Or, you can get oversteer. Then you literally start chasing your tail again.

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Don't mistake rubber bellows on the steering rack or rubber dust boots on tie-rods for rubber bushes in suspension arms and links. Having said that, if they are torn then water and sand will quickly cause play in the ball joints inside them and the part as a whole needs to be replaced, as your tech advised. The diagonal Arms front and rear have a ball joint on the forward end too (don't replace with the EPS version that replaces this with a polyurethane bushing as they snap!). Regarding sway bars/anti-roll bars. Since you're looking to reduce the body roll angle but not necessarily change they way the car behaves in corners (think understeer/neutral/oversteer) my advice would be to buy a set consisting of front and rear ARB as buying only one will not only reduce the body's roll angle but also change cornering behaviour. Eibach or H&R come to mind as offering ARB kits. As others have mentioned at least check condition of anything rubber as well as your shock absorbers but foremost make sure the polyurethane (brown) bump stops around the shock absorbers' piston rods are not perished or even missing. They contribute way more than one would think towards supporting the body during cornering and prevent excessive body roll. Part #9 at the front strut in And #8 at the rear Lowering to RoW ride height by changing springs and fitting new bump stops will help significantly too.

I have a set of sport sway bars (with bushjngs) that i will let go fairly cheap if u want a small upgrade. The next step would be a set of tarret adjustable sways and links. They r just like the gt3 parts. Like others have said swap the motor mounts first as its amazing how much it swings and chech the alignment.

Just enhancing HBs work. Here is a complete quote for rear struts as an example of what a Porsche parts place can do for you. I sent them my VIN and asked them to tell me the parts I needed.

Engine mount kit and numbers: Porsche Engine Mount Kit - Rein 996ENGMTKT | FCP Euro I just installed these mounts in mine. FCP has a nice DIY instal video for this but I still needed advice from this board on how to get the 13mm nuts off. Advice was correct: did not need torch. Needed 6' breaker bar. That worked.

Got under the car. I'm going to gut the whole suspension. Trying to figure out now, Koni Actives with stock springs, or B6's with stock springs or Eiback Pro Kit

I have picked all of my parts (except for shocks) for a complete suspension refresh. Except, does anyone know the parts for all of the nuts?

Interesting. I worked with Pelican and got a parts list together. Need to find part #'s for all of the nuts/screws, but two things Pelican did not flag me as needing are "Spring Insulator" and "Coil Spring Retainer"

Make sure the current sway bar bushings are good, it doesn't take much and they dont do their job well... (This is a 10 min DIY easy task... FYI) 4 bolts.

Thanks. Gutting the whole suspension at this point, so yeah, will buy new bushings for the sway bar (and hope that money doesnt go to waste should I decide I need to upgrade the sway bar after it's all done)

All the hardware can be found in the PET drawings on the Autoatlanta web site. Its a very good resource.

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The only reason you will need to upgrade your sway bar from oem quality is if you are going to track the car so you can correct for 996 understeer that comes purposely from the factory. You won't notice it on the street. Especially if you run a good set of grippy tires at the right tire pressures, a good alignment that doesn't go hog wild on camber so you have a large contact patch for street application and obviously have a good working suspension. Street and track requiremeets and therefore the need for specific parts are night and day different. FWIW, if you someday want to take it to the next level and eliminate body flex, you can put in a half cage or a Brey Krause harness. Since it's a cab, a half cage doesn't make much sense. However, the BK harness is a pretty cool and easy to use solution with a removable harness bar that allows you to use the back seats. They make one for the 996 Cab. While you may never track the car, and therefore not ever need the harness bar (removable), it's an expensive but effective solution to eliminate some flex. No question its overkill, but thought i would toss it out there as a FYI. Below is a link to BK so you can see the black bar that connects over the rear suspension. https://www.bkauto.com/category_s/189.htm