pzull

I think its time to change my RUF shocks as they feel a little soft and bouncy on uneven roads at high speed.

Heard good things from 993 board but has anyone tried the kit for 964s? Any views?

johnfm

They don't make them for the 964 AFAIK.

Christer

ditto. don't you think I would have some by now?

pzull

FVD lists them on their online catalog albeit at a huge premium at 2500+ euros.

Think I'll search some more and get the first set that's closer to a reasonable price. Will post findings if anyone else is interested.

JasonAndreas

There are companies http://www.smartracingproducts.com/p...Order Form.pdf that will custom valve a shock for around $85USD or so. Before you spend $2500 you may want to consider calling them and asking them if they could help with your 964.

pzull

Thanks Jason. I was hoping to get adjustability as I use my car for street and occassional track. Any suggestions other than PSS9s?

Checked with Gert, he doesn't carry them and says that FVD's is in-house tweak or something like that.

tonytaylor

9M did suggest using PSS9`s on my 964 and didn`t think it would be rocket science to make them work but after discusion I didn`t think they would offer the ultimate track set-up, - being too soft, and cost wise offering little over the ubiquituos H+R/Bilstein coilover setup for a road and track compromise.
IMHO the marginal utility of PSS9`s for 964`s is equivicable.

Drew_K

Personally (and your mileage may vary), I would go with an RS setup (semi-track) or something from Smartracing or The Racer's Group (all out track setup). All are reputable setups for a given situation. I'm also not enamored by single adjustable shocks, such as the PSS9 system. I'd go with at least double adjustables or a non-adjustable custom valved shock (e.g., one of the 3 setups I mentioned above). Adjustability loses a lot of its value when rebound and compression have to be adjusted in unision, as in a single adjustable shock, although I do see some benefit in being able to soften the ride up for the street.

Bilstein makes great shocks, and I'm sure the PSS9 system is pretty decent. I'm just throwing a few more ideas out for you to consider.

ljugete

I've heard that Steve Weiner @ RennSport Systems has made a modified U.S. Bilstein PSS-9 kit for the 964 which he combines with front and rear adjustable OEM RS swaybars.

He states that this suspension upgrade is awesome and that his customers have loved it!

The kit goes for about $2,890.00 and the OEM RS swaybar kits front = ~$440.00 & rear =~$480.00 or so. He states these bolt on without the hassle factor and he offers full tech. support for his products.

He is a rennlist sponsor and offers an outstanding service IMHO.

I have called U.S. Bilstein and their tech. representative (?Shawn) told me that they currently have no plans to make a PSS-9 kit for the 964 suspension - only 993, 996 for now.

P.S.: I have no relationship with RennSport Systems. I have just heard alot of good things from some of his customers and have talked with Steve in the past who has been very helpful to me.

I hope this helps!

Bill Gregory

Having the RS suspension (although with thicker rear sway bar), I'd agree with Drew_K that the RS setup is very good for street use and for beginning up to advanced use on the track. As with any progressive spring setup, the suspension has to move through the softer portion of the spring to get to the harder portion, which affects how quickly the suspension will take a set in a turn. This is especially helpful to teach smoothness on the track, as rough handling with progressives can really unbalance things. However, there comes a point in time when you carry much more speed with quicker transitions, where progressive springs can hold you back. At that point, linear springs or linear springs with helpers help you go to the next level.

As my 964 is still dual use, my current plan is to move to 400/600 linear's with the RS shocks. The hot track-oriented setup seems to be 600/750 linear's with revalved Bilsteins, although I wonder if, even with proper valving, that's too stiff for street usage. A related aside, right now I'm taking the rubber bushings out front and rear, and replacing them with monoballs, as well as, finally, installing the Cup steering rack/tie rod couplers, or forks, as Porsche calls them. Will report back in more detail, probably later in September.

pzull

Thanks for all the input. My car can't be an all out track car as its a daily driver. I also go for blasts on B-roads here which can be really bad and an overly stiff suspension might unsettle the car on corners with bad bumps- so I've been told.

Are the Bilstein/H&R coilovers much stiffer than PSS9?

Revalve of the Rufs might be an idea so I'll check it out, though it means my car will be out of action for longer than desired.

joey bagadonuts

I spent the weekend at the PCA Club Race at Road America and it seemed that the new hot setup is comprised of remote-reservoir, double adjustables with ... get this ... spring rates over 1,000 lbs/in!!!

Okay, let me clarify. The folks I talked to were running 993 and 964 stock class race cars ... yes, the RS and RSA variety. One Rennlister, Greg Fishman confirmed that the 1,100/1,250 combo with tender springs were actually less harsh than just the 700-lb linears he used to run. Hmmm. Some other, fast C Class guys were actually considering a change to something heavier. They noted that the front runner was probably using 19's and 20's, i.e. a 1,900/2,000-lb combo.

The best thing about the adjustables seems to be their flexibility. Swapping springs doesn't require revalving, so perhaps there's a bit of savings there. Also, the Moton Clubsports appear to be a relatively affordable option compared to JRZ's and others and they make them for 964s. I'm leaning towards these with some streetable spring rates. I'd like to stay away from the tow vehicle for another year and when it's time to go over 1,000 lbs, I won't need to swap shocks. Well, that's the plan anyway.

Here Moton's website in case you want to read up on them.

0.02

baltazar100

I just purchased the PSS-9 kit. No track driving but quite a bit of spirited early weekend morning rides, usually competimg with modified 'rice cookers..' on winding roads.

Any recommendation for initial set-up ?

AVoyvoda

I had PSS9s fitted on my 964 C4 widebody last year and have been driving around with them daily, ever since. Wheels: 18 inch 8/10. Verdict: Awful, bordering on unacceptable. At low speed, the car crashes over every bump and sometimes "sways" from side to side like a boat. Further, the suspension's "compliance" if that's the correct word, isn't nearly as good as one would expect. At medium speed (> 40 mph) the Bilsteins are quite good, better than the standard Euro set-up. At high speed (>100 mph) very good to excellent. Overall, absolutely not worth the ride deterioration at low speeds though. This is a mod I seriously regret.

I am changing them for a custom KW handling kit that costs about the same. For those that insist on Bilsteins, recommend you also check-out the Bilstein G8 handling kit (springs and shocks). Exactly the same as the PSS9s but non-adjustable, at half the price.

Red rooster

The PSS9 kit on a 993 is VERY good. Set on nearly the softest settings ride quality is better than standard. On hard - very track worthy !

993-964 fronts are the same so what tuners are doing is sorting the damper/spring set up for the 964.
High on my list of future modifications .

Just my $0.02

Geoff