Suspension Options

[Phillip Reynolds]

Hi, this is the first 964 I've owned. When driving the front is quite light and wallows around. I was wondering how much of this is just having a light front end and how much is down to suspension? I'm happy to refresh or upgrade the suspension as needed but didnt want to go into this blind. Not that bothered about lowering the car, just want a good road setup and very occasional track us. Can anyone point me in the right direction.

Thanks

Phillip

 

[tim_haskins]

Lots of us have the bilstein hd shocks
with h&r green springs. Reasonably priced too. I bought mine from
the USA and were
very cheap but you need to watch the import duty. Another option is kW

i think euro do the bilstein shocks and design 911 do kW and bilstein.

I am am happy with my setup and would recommend

tim

 

[Dekker]

Welcome to 964 ownership Phillip.
I second Tim's advice. The shocks are probably worn out if it's done 80k or so. Bilstein HD are a very good replacement better than the originals. As far as springs go you can keep the standard Porsche ones or if you want to firm it up some which would be good on the track, H&R Greens though I think they might be Purples nowadays. With the Bilsteins you can lower it at a later date if you so wish.
Also check the top mounts. The front ones are easily accessible and suffer from de-lamination where the rubber compound separates from the internal fixings. This can also happen at the wishbone bushes, but that should be picked up by your MOT.
Having the suspension adjusted afterwards is a must and there are plenty of places to get it done. I live in Malvern and use Simon at Chemix - Stourbridge who does the full setup for about £80, it's a fixed price and he uses the regular laser kit with a before and after printout.
Check the history before you buy, sometimes new shocks are fitted and only toe in is adjusted. If that is so, just get the car setup properly, it'll transform the driving experience.

 

[Phillip Reynolds]

Thanks for the feedback. Is that B6 or B16's ? Presumably the 16's as the are adjustable? Is Centre Gravity a company that does the setup of your suspension?

Thanks again.

Phillip

 

[Dekker]

Yes B6's are the HD none adjustable and much cheaper.
Yes COG do suspension setup, be prepared for a large bill.

 

[Gordon Attar]

Suggest you also drive another car for comparison as the front end is known to feel a bit light but shouldn't wallow.

 

[Gordon Attar]

<p>Suggest you also drive another car for comparison as the front end is known to feel a bit light but shouldn't wallow. </p>

 

[Phillip Reynolds]

Yes I've heard that the front is light. I think my aim is to apply a recommended setup to my car so that it's as good as it can be. Sounds like Bilsteins are good. Do I go for adjustable? I know Singer use Ohlens but presumably that's aimed at track usage?

Thanks all, your feedback is really useful.

Phillip

 

[ras62]

Is your car still on original suspension? If yes then Bilstein B6 are an excellent upgrade. I have KW which come with springs, these are also excellent, perhaps a touch stiffer than B6. Both Bilstein and KW do adjustable shocks if that is your preference, obviously these cost a substantial amount more. As has already been said a good geometry set up is critical and done by someone who knows these cars, there are several good independents around the country. If your car has already had suspension then it could be just in need of a good geo setup.

 

[mcgc0]

+1 ras62.

Ask anyone who has adjustable how many times they *really* do make an adjustment. Most their life they spend at the same adjustment setting. Very subjective topic and as always it depends... on your driving preferences and style. Dialing out the (default) slight understeer is easy peasy without the need for different ARB's or other expensive purchases etc. Just take to someone like Centre Gravity and for a few hundred they'll reset the geo on your existing set up (assuming it's all in good working condition). You can spend as little or as much as you like. Ohlins are way out there at the top expensive set up and unless you like to track something like a GT3 RS regularly then your Bilsti's or satndard KW's are just fine - it's all down to the geo imho...

 

[Dekker]

I don't feel the front of my car is light, by any means. I have it at RS height with minimal bump steer.
I have B16's (formerly called PSS10'S) which I adjust when I'm on the track. It's relatively easy to adjust them as the adjuster is on the bottom of the strut, KW3's are much more difficult to do unless you've got rid of the airbox and the heater blower to allow easy access to the rear adjusters which are on the top of the struts, inside the engine bay, and are done using an Allen key.

 

[colin129]

Suggest you also drive another car for comparison as the front end is known to feel a bit light but shouldn't wallow.

Interesting Gordon.

I have just come back from a long weekend in Northern Germany, which was really an excuse to finally drive the Autobahn. The car was completely fit, and still putting strong above 130, but as a went up to 140 I felt as if the front end was going light and thought that discretion was required. I GPS verified 143 was a much I felt comfortable with, with the lightness of the steering, although there was clearly plenty left.

Also a note for anyone else who might like to try. As I moved into the middle lane having run at between 120 and 130 for several miles, I could hear an intermittent rubbing sound, also the oil temperature was slighted raised. My first thought was oh blimey, what have I done! I slowed to about 80ish and moved into the inside lane, again the rubbing should. It was only when I have to overtake and move into the middle lane and heard the rubbing again that I realised that the white lines have rumble strips on them, which was causing this apparent rubbing sound. [:-]

 

[Gordon Attar]

Suggest you also drive another car for comparison as the front end is known to feel a bit light but shouldn't wallow.

Interesting Gordon.

I have just come back from a long weekend in Northern Germany, which was really an excuse to finally drive the Autobahn. The car was completely fit, and still putting strong above 130, but as a went up to 140 I felt as if the front end was going light and thought that discretion was required. I GPS verified 143 was a much I felt comfortable with, with the lightness of the steering, although there was clearly plenty left.

Thats describes a 964 exactly, its a bit disconcerting to start with, then fine when your used to it.

 

[Steve Brookes]

To get the front of a 964 to feel 'planted' at high speed and have a nice weighty feel to the steering you need to get close to max caster on the front wheels, which is 4 25, when having the geometry done.

 

[colin129]

Thats describes a 964 exactly, its a bit disconcerting to start with, then fine when your used to it.

Your suggesting I should have just driven through it?

 

[mcgc0]

As with Steve earlier... RS front castor closer to 4o 05' against which I have my C4 set. With an adjusted front camber it's perfect (for me anyway). Centre Gravity re-geo'd and straight after I was in Scotland doing an extended ECOTY / North Coast 500 (actually covered 750 miles in 3 days). The set up was perfect for the great ribbons of tarmac and awesome mixture of fast twists, open hairpins and bends. Front end confidence allowed me to plant early then feather the throttle the moment I saw the apex. No front lightness at any speed - although suspect the front diff has a lot to do with that. Fast autobahn speeds with any cross winds though would contribute to any feel of lightness..

 

[colin129]

The question is, am I going to go flying off the road in a blaze of flames & twisted metal, or, as long as I hold my line, the car will track straight & true, despite the disconcerting feel?

 

[mcgc0]

How good are your reaction times Colin? []

Two options imho; a) go somewhere like Bedford Autodrome on one of their track afternoons and find out (plenty of run off there) or b) nip up to Atherstone and let Centre Gravity give you an assesment and test run.

 

[RLambert]

My car was totally standard and was awful to drive fast. I took it around Snetterton and it felt quite dangerous, lurching left to right and front to back and difficult to manage the weight transfer. I can see why people crash them!

So I've gone with Bilstein B6 with tender and main springs, bushes, anti-roll bars are standard. I worked with Chris from COG to work out the right combination and here are the notes from Chris below. The spring combination is a better approach than a single progressive spring. The tender spring soaks up small bumps but when pushing on the main spring takes over.

Front free spring length should be circa 200mm (as pss10)
Front tender should be at least circa 70mm part closed to stop spring slap at full droop
In my opinion you should use front tenders 50-60-0020 (78mm free length 114Ib) or 50-60-0030 (90mm free length)

Rear spring free length should be 180-200mm
Rear tender spring should be circa 80mm to reduce spring slap at full droop
Rear springs;
Definitely go with the 200-60-80 457lb springs
Tenders either 40-60-0040 free length 75mm or 50-60-0030 free length 90mm rate 171lb

The tenders will go to block car static, however the higher rates will make coming off turn more progressive

I had a set up done by Jaz, the car is slightly lower than standard and handles superbly. I used to race one so I know what a good set up is like. The only down side is it is a bit crashy over bumps, I think the tender springs could be a bit harder so they absorb the small bumps better. I also run 17 inch Cup 2 with Bridgestone S02A tyres.

The car is great, totally stable at all speeds and I regularly take it past 150 and even had it off the clock once with no dramas. On a circuit the car is very progressive and doesn't do anything nasty.

I think people overdo it when 'upgrading' their cars changing everything and whilst that might make the car quicker in the hands of a pro racing driver for a regular Joe they won't get the benefit of it. At Donington in my road car I was only a couple of seconds off my race lap time in my 964C2 race car.

 

[Dekker]

Walter Rohrl says....
"If you asked me which I thought was the purest drive, I would have to say the 964 though…"

You had new Bilsteins fitted to your 964 RS. As a test driver, how important is suspension setup in the design process of a new racing model?
"I would say that it is the most important thing. On a race track, it is relatively easy to make sure that engines are levelled. So, suspension can give you the only advantage.

Look at the other elements of the car; tyres, aero, brakes. There is no point trying to perfect these until the chassis is working properly. The 964 RS, which I regard to be one of the best cars to drive is a great example. From the factory it is too hard up front compared to other Porsche models. It has a hard spring and a soft damper. When you change to the BILSTEIN PSS10 kit, you can really make the car drive much better.
When I drive mine on track I run six clicks on the front and nine on the rear. On the road I run ‘three’ front and ‘seven’ rear. Set like that, the car drives perfectly! If you have this car, you should try it!"