kkim

I'm planning to finally install my PSS9s in a few weeks after buying them back in January. I believe I have all the parts I need and am looking for feedback from those that have done this install on their own. I don't have the luxury, like the majority of you, of just taking my car to the installer and having the work done for me. As such, I will DIY the installation, ride height setting and helping out with the alignment at the alignment shop due to their inexperience with working on 993s. I will forego corner balancing as I can't find anyone on this island with scales. Hopefully, setting the proper ride height will get me close enough.

I know basically what it is I need to do after reading Robin's DIY on suspension installation and the many posts in the archives after countless searches on various aspects on the job ahead. However, I do have many detail questions that I hope others can help answer.

From reading other posts I have decided on PSS9 initial settings of 5f/5r. Ride height of approx. 25 3/4"F , 25 1/4"R. Actual measurements will depend on how low I can get the rear of the car after I install the PSS9s.


Installation-

1. The PSS9s come with rear shock mounting "collars" for the top of the shock. Which way does this collar install? Hollow side up or hollow side down?

2. I plan to use a second locking ring on the sway bar mount on the rear PSS9 shock to avoid having the sway bracket come loose. Should the second locking ring go above or below the sway bar mounting bracket? or can I...

3. eliminate the shock spring seat locking ring and move the 2 sway bar mounting bracket locking rings below the bracket? Any downsides to this approach?


Ride height setting-

1. When setting the rear sway bar bracket height, I understand there should be no preload on the sway bar when it attaches to the sway bracket. Is this with the car in the air or on the ground?


Alignment-

1- I have purchased a rear kinematic toe gauge from Autometrics Motorsports. I know absolutely nothing on how to use this gauge in reference to setting the kinematic toe. Anyone with experience with this gauge care to help me out on what to look for when setting this toe value?

2. For aggressive street use (lots of mountain road use), what camber/toe measurements should I go with? I want to balance grip w/ tire life. My last set of rear tires went 3500 miles before having to be changed. The wear was surprisingly even w/ slightly more wear on the inside edges.



If you can help with any of the above questions, I would really appreciate it before I get into the install and find out I overlooked something.

Thanks all

solsrch

Kim,
A few things.
ViperBob has a great info sheet he'd probably be willing to share with you. As you have probably already seen the Bilstein directions, while certainly correct, leave something to be desired. Robin's are much better but there are still a few areas that can use some illuminating.
As I remember the hollow side goes up the collar but I won't swear to that. I didn't use any extra locking rings, so I won't even touch that one. The sway bar will be attached with the car in the air; there won't be any preload. All I know about alignment is how to write the check. Although, I marked everything as Robin suggested and frankly, didn't really feel any difference before and after the high speed, low drag alignment was complete at the shop. Ride height adjustment was where I was off. Somehow got the back lowered more than the front, so the rake just didn't look right. If you are doing the sway bars too, I thought the front sway bar was the hardest part of the whole thing. Oh, and getting that one bolt out of the left rear assembly.

kkim

Thanks, Joe.

I already have ViperBobs instructions as that is where I got the PSS9s from. Certainly much better than the generic Bilstein instructions included w/ the kit.

Regarding the sway bar attachment while in the air. Won't that preload the suspension when you put the car back on the ground? Is that what you want to do? I thought the idea was to have the bar in it's static state when at rest on the ground so it doesn't influence the ride height.

Thanks for taking the time to run through your experience with the install. It helps firm up the steps I need to take to get this completed.

Travis

Hi Kim,

I recently installed the PSS9 setup with stock sway bars. I was able to set the rear coilovers using the Bilstein docs as a 'guide' and was able to get the rear ride height to 25 in. rear and 24.5 in. front. Of course, using the p-car.com pictures and instructions was the main set of information I leaned on.

As others have said, using the Bilstein short sway bar links with the standard bar, the attachment is above the control arm. I have about 3-4 mm clearance with everything connected and suspension completely off the ground. No contact with anything.

I pre-loaded the swaybar a bit using a jack under the coilover. Then once the wheels were on, I tightened the links to the final torque specs. Did this mainly to see the whole articulation of the sway bar/link and clearance with the control arm.

As for lockrings, I left everything on the coilover as it was delivered. There's 3 lockrings between the lower spring and the sway bar mount. All three lock rings are pretty much one on top of another.

Let me know if you need any pics. JeffTT's pic of the pss9 with stock sway bar pretty much looks exactly like what mine does.

hope that helps,

kkim

Travis,

Thank you for the numbers you provided. I am frankly surprised you were able to get the 24.5f/25r measurements that you did. Isn't that RS height? It is encouraging to see that the stock sway setup will go that low. BTW, shouldn't that be 25f and 24.5r to get the proper rake?

Your measurement of 3-4mm of clearance is also helpful so that I at least will have a guide as to what will work once I get everything buttoned back up.

Any pictures of the shock/lockring configuration and also of the completed car to see what your final height looks like?

Interesting stuff....

Thanks,
Kelly

PBenz

Kelly,

Just a quick note about the ride height - the shop manual states that ride height is measured in the front as the "distance from the road contact surface point to bottom of bolt head of outer cross-member-to-body bolt connection." For the back, it is measured from "the road contact surface to rear mating face on the bottom of the suspension subframe". Since I don't know how this translates to the measurements I see on this forum, and because it is virtually impossible to get under the car and measure ride height "the shop manual way" after installing the PSS-9s, I didn't touch the ride height at all and left this up to the alignment shop.

I settled on ROW ride height which I'm very happy with in term of looks and "compatibility" with speed bumps.

Also, you'll be able to easily change your firmness settings with the car on the ground. Rears are no problem, and fronts are accessible by turning the wheel one way or the other.

kkim

Thanks, Paul.

Check your PM.

solsrch

Kim,
I understand your question but I think the thing is that the sway bar can easily move up and down. I believe the torque that makes the sway bar transfer force or work, or whatever the right term is, that force is created whenever anything tries to make the car lean over. This attempts to change the angle on one versus the other side. So, installed, but not buttoned up to the wheel assembly, it will freely rotate up and down. I don't think attaching it in the air creates much, if any, preload. It does its job as the car attempts to lean. Does that make sense?
Joe

kkim

Actually, Joe, your explanation does make sense. I thought about it after I posted and realized it's the twisting motion that the sway bar resists. If both sides move up and down in unison, the bar doesn't do anything. So, as long as the sway bar ends can be mounted to the brackets w/o any tension on either side, that means the bracket heights are even and no preloading will occur.

Thanks for clearing that up for me. One less thing to worry about as I put things back together.

Travis

Hi Kelly,

I'll take a pic of the rear suspension tomorrow.

Posted a thread last week on the glam shot of the post PSS9 result.

See: https://rennlist.com/forums/showthre...hreadid=145662
For the picture of the car.

The measurements of the front and rear with the lower fender number for the front gives the nose down rake you will likely want. So, yes, the front is 24.5 and the rear is 25.

Hope that helps,

kkim

Travis,

Thanks for taking the time to take a pic.

I am very interested in your setup as I have not heard of others getting the ride heights you have while using the stock sway bar setup. Did you do anything else different w/ the sway bar links or sway bar mounting bracket modifications?

Also, I was under the impression that to get the proper rake angle of 1 degree the cars, the front height measurement should work out about 1/2" higher than the rear height. With your heights, it would seem the angle would be steeper than the recommended 1 degree.

I do like how your car looks, though.

TroyN

I had emailed Steve Weiner about this before, and he said:

Look too at the heights that Porsche spec'd for various setups, eg. stock, M030, RS, to get some ideas, there is definitely some lee-way there. Even all around seems pretty good.

Travis

Kelly,

Here's a pic of the rear PSS9. As you can see, the swaybar link is close to the control arm, but it's not touching. (hard to see from this angle).

This is as low as I can go because of the clearance issues. If I get different bars and links, there will definitely be more leeway.

Hope this helps,

kkim

Troy-
I think my final height will be determined by how low I can go with the rear sway setting. I will have to give strong consideration as to the front/ rear height suggestion as I would like to keep the proper rake, but I also think the front sits too high relative to the rear in stock form.

Travis-
Thanks for the pic! sigh... time to start counting threads on your shock to see where I need to position the brackect to obtain the height that you did.

Travis

Hi Kelly,

Counting threads, hmmm.

I measured from the top of the sway bar bracket to the middle of the hole where the shock mounts to the control arm, 175 mm, roughly 6 7/8 inches.

Look at page with the diagram of the rear coilover assembly that came with the PSS9 box. I used the 175 mm distance and it was what I used with the install.

hope that helps,