Clanking PSS9

arcticsilver · #1 (**permalink**) 09-05-2007, 04:59 PM

I recently had PSS9s coilovers installed and, although I like them on the track, I hear a relatively loud "clanking" noise from the right rear shock (and sometimes the left rear) when the shocks are unloaded as in going over mild bumps. This was not present with stock shocks, nor is it present on the front shocks at all and mostly on the right rear. I talked to Carl at Imagine Auto, who installed them, who heard it too. He checked that everything was tightened and concluded it might be the aftermarket exhaust which did have some clearance problems. However, I have since installed a new exhaust with no issues about contacting parts of the car and I still have the same clanking noise in the right rear while going over bumps. Does anyone with PSS9s have any thoughts or suggestions?

Kor · #2 (**permalink**) 09-05-2007, 05:19 PM

I once had this happen with coilovers. The shop couldn't find where the clank came from. I told them to take the coilovers out of my car then put them in again. They did it, problem solved.

When a car is up on a lift it can be very hard to see if something isn't aligned properly or if a bolt is not all the way in etc. But by doing it all over they re-tightened and re-aligned every piece.

Anyway good luck.

motionless · #3 (**permalink**) 09-05-2007, 05:21 PM

I have the same issue. Uninstalled, reinstalled, tightened, loosened, u name it, we tried it. No solution yet.

arcticsilver · #4 (**permalink**) 09-05-2007, 05:39 PM

I know you mentioned this to me before. I just wanted to see if others with PSS9s shared our experience. I called the US distributor in North Carolina who is sending me the parts list with pictures and installation instructions (which I never saw), etc, to make sure we don't have a convex washer installed the wrong way, or something. Do you think it is associated with the upper mount or spring rates that lead to spring separation at the upper mount under unloading conditions? You installed these yourself. What did you have to remove in the rear hatch area to access the mount bolts? Do you think there could be a rubber bushing or rubber shock plate that could have been left out of our kits?

arcticsilver · #5 (**permalink**) 10-21-2007, 10:59 PM

I have corrected the "clanking" sound from my PSS9s. They were originally installed 1 3/4" lower than stock, too low for my taste for the street. The right rear also "clanked" when unloaded over bumps, the right rear also did that occasionally. I recently cranked up the height a little to gain more road clearance, and the clanking totally stopped. At the maximum lowered level (1 3/4" below stock in my case) I think the springs separated from the upper strut mount when they were unloaded (over certain bumps). Now they don't. If anyone else had that problem, try raising the rear height a little. I re-aligned after I adjusted the ride height keeping as much negative camber as I could. I will have to look at the sheets to see what camber I ended up with, I think 1.75 degrees negative at the rear and the front somewhat less.

**glenn** · #6 (**permalink**) 10-29-2007, 01:18 PM

I am just guessing that your shocks are hitting the bumpstops. I would think that a lowered car going over a street bump could cause the shock to bottom out.

My Porsche technical support guru has been installing Bilstein shocks on Porsche's for years and has seen that the Bilsteins when set low for the track, don't have enough travel. He called an engineer at Bilstein and got him to tell us how much overkill was in the bumpstops in the Cayman PSS9 shocks.

We were able to disassemble the shock and cut the stops down almost in half. Gave me plenty of travel for the track and street even after lowering the car about 40mm.

I would not do this, unless you know what you are doing. Find an old school Porsche race car builder, who can take the Bilsteins apart. If you need specs on how much of the bumps stop you can cut out, let me know and I will make some calls.