Thanks for the insight Ken. Very interesting reading and curious findings. I think the main thing to keep in mind is that... GT2 specs were designed for the GT2 and not the Turbo.

Based on your earlier findings I decided to not go with the GT2 ride height but a happy medium between ROW turbo and GT2... 130mm front and 140mm rear.

At first glance it aesthetically appeared to be a bit high but I have rationalized my decision due to the fact that one, my car is a daily driver on mediocre streets and two, I will soon be changing to a 19" wheel and different tires. At the time of the change I will re-evaluate the performance and aestetics of the ride height and dampening settings and adjust accordingly.

I have great convidence in stating that you are more intune with the performability and engineering of your car than 95% of the people that own 996TTs and your research is very impressive. But for the most of us we will never push the cars to the limits you described... however it is nice to know what may be encountered should any of us go there.

I hope I like my PSS9s... installed yesterday. Upon driving the car home from the shop this morning... the car rides and handles much better than stock and is far more responsive. I'm sure that after a proper alignment the car will feel and perform even better.

Thanks for the info and keep up the good work.

 

When I installed the PSS9's I just went by the board posts, most saying they were the best things since sliced bread, I did not do any research (shame on me!)
Honestly though I believe that most of these guys that love this system either do not drive their cars hard enough to feel the instability or their cars arent as low as mine and KPV's

If I could do it all over again I would have spent the extra money and went with the Motons, nothing else

My past 2 cars were rock solid stable at mid triple digit speeds with very little or no correction needed in turns (Diablo and 512TR)
In fact the faster you went the better it felt, the Turbo will never feel like that on the bump stops.

I am doing too many mods right now to change suspension so for now I will have to live with the condition because I refuse to raise the ride height or swap out the 19's
I really respect KPV for going into such depth on this subject and picking everyones brain, someone had to do it and I cant think of a better candidate, Ken I feel your pain, lets go buy GT2's and start the modding process over again and by the way do you have an extra bedroom if I do buy a GT2? , I promised my wife I would never mod my TT, yeah right!

 

Ken, thanks to all our meets and triple digit speeds and your brains we all agree the PSS9's with such a lowered ride height do not work for those pushing the limits. I think Ron puts it best by saying to buy the GT2's, I just hope we get a good deal for buying 3 of them. I think I will also need a room in your house pretty soon Great work buddy!!!!

 

How does the Row 030 and x73 suspension drop ride height by 10 and 20mm respectively with no adverse affect given this information? Does this mean those with PSS9 or H&R coilovers need to raise their suspension to near stock levels to maximize the TT suspension design? What about the comment regarding the Moton kit? How can this help if all the issues mention by Ken are not addressed? This is great stuff and the info is crucial.

 

Hmmmm...maybe an extra 3rd room.

Now 4 GT2s....come on...a great deal is inevitable!

The dealer keeps calling me about that blue GT2, I could see if he could get 3 others! LOL!


Tony...for now, Im done...well after the secret weapon arrives that is....

 

Hmmmmmm.... What secret weapon?

How does the car feel Bill, I know it looks great!

 

Ron,

Secret weapon.....You'll know in about 2 weeks!

The car felt pretty good....just like I expected. I didnt have a chance to really get on it, like we normally do, so i'll have to wait until this coming week.

Thanks again!!! Always appreciated!

Btw...for those that are in the NJ area and looking to get any suspension, alignment work, wheel balancing....Ron aka Vipertestarossa is your man! State of the art Hunter machines and of course...as always, top notch customer service!

 

Thanks for the compliments Bill

Always glad to help!

 

Great thread,

Lots of interesting information.

thanks

 

Great post Ken!!! I have never learned so much about Porsche suspension dynamics in one thread. Thanks to the other great information contributors too. I know you will get this resolved one way or another, especially since you need and deserve high speed stability.... You and and few others on this forum truly drive their cars to the limit...

I have another license plate idea for you: NO POSER

 

ROW Turbo is 20mm F/10 mm R lower than US Turbo.
X73 ( the factory sport suspension option in Europe , but avail here through importers ) is 30mm lower than ROW Turbo , so it's 50mm F/40mm R lower than stock US ride height.

 

Ron,
We shall see what the next week will bring in terms of info and decisions. I will definitely be changing out my rear donuts and kinematic toe link. Hopefully that will solve the high speed instability as long as I keep the 9's set at No. 1.

Tony,
Any dealers out there wanna offer us three GT2's for a group buy? Am I serious? Tony and Ron know.

NelsonF,
The ROW ride height is listed below. Since the ROW and X73 pacjjkages are Porsche spec'd packages, it stands to reason that they engineered the correct amount of shock travel into the systems. I would assume, however, and it is an assumption, that the CA and STR are both angled upward since I would assume the wheel carriers are the same. So, the travel and suspension compliance are addressed, but bump steer may be evident in extreme road conditions.
I cannot speak for the H&R systems since I do not have the neccessary information pertaining to them, but the PSS-9's should not be lowered to GT2 ride height, plain and simple. It has become apparent they accomplish three things:

1. They offer an improved ride.
2. They offer damper stiffness adjustability.
3. They allow some ride height adjustability of the car within reason.

The Motons, as far as I can tell so far, offers the correct shock travel due to their customizability. The CA and STR angles really should be fixed but we are still figuring out how to deal with both. Gary sent me a sketch of an idea that will deal with the CA so we may have it licked. The rear donuts should be replaced for anyone intending on high speed driving through curves.

Billy,
I only have four bedrooms and I am already in one of them. It is first come, first served baby!!! Get that GT2 order in!


Chris,
I like the plate idea!! So which is it? EL LOCO or NOPOSER

MKW,
I must disagree. The ride heights for the USA Turbo, ROW Turbo and GT2 are listed below:

• USA Turbo
  Front 148mm to 168mm
  Rear 148mm to 168mm
• ROW Turbo
  Front 128mm to 148mm
  Rear 138mm to 158mm
• GT2
  Front 108mm to 118mm
  Rear 133mm to 143mm

As stated, I am at:
Front 113mm
Rear 134mm
The X73 ride height should fall between the ROW Turbo and the GT2. By your statement, the X73 would be lower than the GT2.
Was this a typo? Do you know the real ride height of the X73 setup? Anyone?

 

Ken,
don't have the exact spec on the X73 and yet seen one, but here is a pic of X74 on C2. looks pretty low to me.

 

Arling what color anodized is that on those K28's??? Looks goldish...

 

Arling,
That is definitely higher than GT2 height. Here is a picture of mine for comparison. Bad angle, but it is all I had on such short notice


This picture reflects 113mm in the front and 134mm in the rear.