A Thesis Paper's Worth Of Info On PSS9 Coilovers

First off , Let me give credit to KPV on 6speedonline who i am copying this info from. here is a very comprehensive pair of threads that discuss the effects of uberlowering using the PSS9 suspensions. i thought it might be worth posting here for those who were considering the move. Thread 1 Thread 2

I would seriously advise anybody considering pss9's for hard track use to read this post and reconsider your options. After reading this and making my own inquiries, I would be nuts to go with anything other than factory peices. I know the majority of guys who have done this mod have done so for bling/looks and will never drive their cars hard enough to make a difference. Do you think most guys who do pss9's actually go thru what Ken did? I doubt it, nor did the 'tuners' who intalled them. Off my soapbox.

I've had PSS9's on my 40th, which improved it's overall handling on city streets and on the track. That was an interesting thread. Thanks for the information. I'm glad I have a mechanic that knows what he's doing.

my car is suffering from the same symptoms the KPV's is PSS-9's with limited travel due to lowing (i bought it this way) i will be raising the car soon to gain some more travel in the suspension and allow the shocks to work. Right now i will not planning on returning to the stock setup (sport suspension) but may depending on what class i will run it (auto-x. stock) or moving to the Moton CS shocks either way the PSS-9 is eventually out. i did post some issues i experianced durring the last skills days on another thread (no replies, interestingly enough) Right now - i am in the camp that the PSS-9 solution is not the way to go if you are looking at streetable - track setup. otherwise stick with the stock stuff

I know and talked to KPV a lot about this back in the day also because I did have this symptom too when I had PSS9s. As far as he was talking back then and as far as I know this was applicabable to the Turbo/C4S kits and not the narrowbody kits which are different. Lowering on a C2 doesn't seem to cause any "pogoing" due to riding on the bump stops since they seem to be lower down than on the Turbo kits. As far as track kits go, do Motons or JRZs. For the street and occasional track stuff we do PSS9s for most folks and then for the more serious track guys/girls we use Motons and/or JRZs...

Got pss9's on my C2 and have had no problems.

Exactly We've never had any issues with installs on a C2. Just the TT/C4s widebody cars.

I have PSS9s on my C2, and after I paid someone to completely "tune" the suspension, it handles outstandingly well. My instructors at DE and autox also commented on how well the car is handling. With respect to C2s, the only thing I think you need to do is have a professional who knows suspensions very well install and tune your suspension. I cannot imagine using stock parts.

^ god to hear the you narrow body folks havn't had problems. how high to PSS9's look when they are are maximum ride height? i've heard that they are still at X73 (or X74, i don't know which is which anymore) or RoW M030 height, which isn't bad at all in either case.

Mine is actually much lower than RoW ride height currently - i just lost my laptops HD or i would post some pictures. so there is a limit to the amount you can lower a C2. i do not have issues with the rear stability- just reduced shock piston travel leading to a non-linear rebound of the wheels. this is really not evident in anything but very hard driving. i am going to raise the ride height to near GT3 Mk1 specs as the first stage (+1-1.5 inches) which should allow the shocks to work as designed, as well as adding gt-3 sway bars F/R. i am picking up where the PO left off in this dev cycle not knocking PSS-9's they are good gear - just may not be right for me in my case

^ what about revalving and going for harder springs?

Somehow, I can't believe c2 narrowbodies are magically immune, while c4s/tt's are plagued. I would bet that a lot of the c2's with them have'nt been pushed 10/10 on the track, or are pure street cars. I think if you push them hard enough, gt2 style lowering will take it's toll on c2's as well. jmo

thought of re-valving and switching springs - couple of issues with that though...I depends on the class i run in - if i go stock classes then it's just wasted $ b/c i will have to swap in the M030 shocks and springs. if i run street prepared which i believe allows 2-way shocks, the Motons are the better setup. i am going to try raising ride height first and adding the GT-3 sway bars before going any further. C2's are not imune to this - it just depends on the ride height for comparisions sake (auto X setup by a local shop here in town) Total Weight 3278 (w/155 lbs driver) Front -1.6 -0.50 Camber 7.9 6.50 Caster 0.01 0.18 Toe Front Cross 0.1 Camber 0.0 Caster 0.01 Total Toe 0.15 set back Rear -2.00 -2.00 Camber 0.11 0.10 Toe Rear Cross 0.21 Total Toe 0.01 Thrust angle I need to double check the ride height <edit> but it is lower than GT-3/2 ride height</edit>

Actually they ARE different kits and the bump stops (which cause the problem on the Turbos) are not in the same "Zone" so to speak so you can lower the C2 far more without the problems associated with lowering on the Turbos. Riding on the bump stops, which is what a lot of lowered turbo PSS9 cars end up doing is what causes these problems... You don't ride on the bump stops on a lowered C2 996 with PSS9s and can lower further on those kits. Typically lowering more than 1.5 inches with PSS9s on the turbo and you're on the bump stops. Been there, done it and installed it too many times to know

Alex, to clarify, they are both prone to the problem but the C2 is markedly less due to different mounting positions relative to the bump stops. Sounds reasonable. Chris

C4s Surgeon, I am not reading the same thing you are. I have heard many issues with the C4s, but NONE with the C2s. The suspensions really are remarkably different and share little to none of the same components. I think it is more than just a minor difference in relative mounting positions. Of course, a C2 could have problems if it is not aligned correctly or if the shocks are set incorrectly, but I have never heard of the "bump stop" type problem associated with C4s, C4Ss, or Turbos. I would bet that the problem with Rob's car is due to incorrect setup for his car/driving, but that it is not the same type of problem experienced by the AWD models. Of course, I have never seen Rob's car, so my opinion is worthless and only an opinion. I know that I don't know it all, so I mean no insult by my opinion. For what its worth, I use my car on the street and the track, and the PSS9s work great for me NOW that they have been set up correctly. When they were first installed, the rears were set too soft, and each were set at a different setting. It handled much better than stock, but it still "skipped" through hard corners. Now that it has been tuned in, the car sticks like glue. It may be a little stiff for the street, but I bought a sportscar and I like that feel TD in DC

Great Thread all! I have been looking at the PSS9's for my '02 C2. I track my 986 quite a bit and I've modified my stock set up with new springs, shocks, and bars. This adjustment have given me much more secure handling at the track but it has compromised the street ride and (still) does not allow me to corner balance the car. I have been considering the PSS9's for my 996 due to the adjustibility that they provide (plus the side benefit of a less compromised street ride). The 996TT thread is interesting because I have not heard anything but glowing recommendations for the PSS9's from friends that have fitted them to their 986's. It is good to hear from sharkster that C2's do not seem to exhibit the same problems with PSS9's at the 996TT's. My questions are......for those that have the PSS9's on your c2's what ride heights are you using? Does anyone have the ride heights for the GT3 MkII (that was the ride height I was planning on using). Comments? Advice?

There we go- perfectly said

i'll measure the ride height this weekend and we will see where we are with this (posted the alignment spec earlier). just to reiterate what "I Think" is the issue - the car is set too low limited travel of the shock piston Add to this the reletive modest increse in spring rate with the PSS-9 system + my driving style = an issue for me. I believe the suspension is fully compressed in a some corners (skid pad/Auto-x situation). throw in the uneven surface we play on up here (bremerton raceway, an air strip track). and that is where i am at. i have not had the 996 on the track so i cannot evaluate it there. Also just to throw something else into the mix - i am comming from a 92 carrera cup car with the series race suspension (600/900 lbs springs, Blistien cup shocks, (later moton 2-ways (not CS) etc.) so i am a bit biased as to setup. This undouptably is tempering my view of the PSS- system. here is a picture of the ride height

Interesting points raised. Thanks for posting. Firms up my decision to go with the X73/74 when the time comes.

Rob, Could it be that you need to choose stiffer settings on your PSS9s? I had problems with my car when my rears were set too soft. No problem once everything was adjusted correctly. TD in DC

How easy is it to change the damping of the PSS9's.... what is the process and how long does it take? do you have to take wheels off? I had a 92 Mr2 Turbo and had GAB adjustables... adjustment was super easy... just take the shock tower cap off and adjust from 1-5 with a small screwdriver... adjust 4 shocks = 5 minutes.

yes i think stiffer springs would help - but the question is do iwant to invest in this system or one that is more suited to what and how i drive.

just twist the lil adjuster ****. i don't think you even need 2 take off the wheels to access it.

I will be doing the x73 on mine, can't outsmart the factory on this one.

I wasn't really talking about stiffer springs. I meant make the dampening stiffer. That's what helped me.