964 C4. Which suspension upgrade?

964 C4. Which suspension upgrade?

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Blib

Original Poster:

43,975 posts

197 months

Wednesday 20th August 2014
quotequote all
Two months after buying my 1990, 964, C4 targa and with 750 varied miles driven, it's time to begin to upgrade.

I've already decided to buy a new set of rear indicators and centre lamp bar which I'm picking up from Design 911 on Tuesday. And, over the winter, I'd like to get the car resprayed as the paint is looking tired.

However, one thing I really want to upgrade, sooner, rather than later, is the suspension. After years of Maserati ownership, the 964 is my first Porsche and it's still fitted with the factory suspension. Which, after a quarter of a century, is pretty worn out. Last weekend I took the car up to Suffolk and although the car was extremely stable and sure footed, it was quite 'crashy' in potholes and gave a pretty firm ride.

For years I owned a Hawk Stratos replica and in one of those, a hard ride comes as standard. So, a hard ride, per se, is not off putting to me in itself. It's just that I don't necessarily want this in the 964. Hence this thread.

I've looked at the various manufacturers' offerings. Those from KW, Bilstein, Koni etc and I've got myself in a right muddle. I'm sure you guys can help me get sorted out.

What I'm looking for is a suspension that will give me a responsive but comfortable ride. Not full on sports hard. I will not be tracking the car at all. It's just going to be used as a summer car with trips to Le Mans just about the furthest it's going to go in one hit. I'm not looking for barge like waftiness. Nor do I want an infinitely adjustable suspension. Just something that can handle the vagaries of the average British A road with a bit more aplomb that the standard, tired set up.

I would like to lower the car a teeny bit too. But, I assume that this will affect the ride and my choice of suspension.

Should I concern myself with anti roll bars?

So, what would you advise me to consider? I really would appreciate some guidance on this as I don't want to spend several thousand pounds on a set up that's too hard core for my needs.

Thanks.


OlberJ

14,101 posts

233 months

Wednesday 20th August 2014
quotequote all
I love the KWs on mine. They are fantastic for fast road use. Set a little above RS height they give plenty of control.

They don't crash but they are quite stiff so maybe not quite what you are after. Defo worth trying though, I've never had suspension like it.

Blib

Original Poster:

43,975 posts

197 months

Wednesday 20th August 2014
quotequote all
Thanks OlberJ. Which model KWs do you have fitted?

mr pg

1,954 posts

205 months

Wednesday 20th August 2014
quotequote all
Add a front strut brace. It's a very easy DIY job.

OlberJ

14,101 posts

233 months

Wednesday 20th August 2014
quotequote all
It's V1s on mine.

uktrailmonster

4,827 posts

200 months

Wednesday 20th August 2014
quotequote all
Bilstein is all you need for fast road use.

I had KWV3s on my 996 (fitted by previous owner) and they were too harsh for UK roads. More of a track day setup really.
Just make sure all the bushes and joints are in top notch condition, fit a set of fresh Bilstein HDs, decent geometry check and it should be good to go. BTW I had a 964RS back in the day on stock RS suspension and the ride was terrible, so I wouldn't try to emulate that for road use!

Don't need a strut brace either. You wouldn't notice any difference unless pushing very hard on a track. Complete waste of money IMO.


Blib

Original Poster:

43,975 posts

197 months

Wednesday 20th August 2014
quotequote all
Thank you for that, both of you. smile

I've heard Bilsteins mentioned as being a good upgrade. Does anyone have experience with them on a 964?

Blib

Original Poster:

43,975 posts

197 months

Wednesday 20th August 2014
quotequote all
uktrailmonster said:
Bilstein is all you need for fast road use.

I had KWV3s on my 996 (fitted by previous owner) and they were too harsh for UK roads. More of a track day setup really.
Just make sure all the bushes and joints are in top notch condition, fit a set of fresh Bilstein HDs, decent geometry check and it should be good to go. BTW I had a 964RS back in the day on stock RS suspension and the ride was terrible, so I wouldn't try to emulate that for road use!

Don't need a strut brace either. You wouldn't notice any difference unless pushing very hard on a track. Complete waste of money IMO.
You answered my question before I posted it! hehe

N24

1,113 posts

239 months

Wednesday 20th August 2014
quotequote all
Bilsteins plus H&R springs is the route to go - check the rears are for a targa (went through this ordeal earlier this year).
Worth signing up on rennlist for the 964 forum - a wealth of detailed info there: http://rennlist.com/forums/964-forum-59


Blib

Original Poster:

43,975 posts

197 months

Wednesday 20th August 2014
quotequote all
Thanks. smile

mr pg

1,954 posts

205 months

Wednesday 20th August 2014
quotequote all
A strut brace IS worth fitting, due to the large gap in the roof! Tightened up my car. Cheap and easy.

Blib

Original Poster:

43,975 posts

197 months

Wednesday 20th August 2014
quotequote all
mr pg said:
A strut brace IS worth fitting, due to the large gap in the roof! Tightened up my car. Cheap and easy.
Yes, I did think that a targa would be a bit more 'flexy'.....

Encantada

3,975 posts

253 months

Wednesday 20th August 2014
quotequote all
Bilstein Hd with h&r greens on mine, RS. Anti roll bars, and front drop links, but running on 18's so a touch hard, if you're near Colchester way, happy to give you a pax ride.

Kevin.


Geneve

3,859 posts

219 months

Wednesday 20th August 2014
quotequote all
mr pg said:
A strut brace IS worth fitting, due to the large gap in the roof! Tightened up my car. Cheap and easy.
A strut brace can be a useful addition for older cars - many pre-74 cars have them to allow more accurate and reliable geo set ups - noticeable even in road use.

shoestring7

6,138 posts

246 months

Wednesday 20th August 2014
quotequote all
If you're looking for a decent ride I'd suggest the Koni FSD system. It has two speed operation that gives a nice ride but still decent body control. Its good value too leaving budget for a refresh of all the bushes (use standard Porsche stuff), top mounts etc. as well as a proper geo job.

http://www.demon-tweeks.co.uk/performance/shock-ab...

SS7
Some more relevant experience here: http://www.pistonheads.com/gassing/topic.asp?t=109...


Edited by shoestring7 on Wednesday 20th August 21:43

uktrailmonster

4,827 posts

200 months

Wednesday 20th August 2014
quotequote all
Geneve said:
A strut brace can be a useful addition for older cars - many pre-74 cars have them to allow more accurate and reliable geo set ups - noticeable even in road use.
Had this discussion a couple of years ago with Tuthills. General consensus was that for road use you wouldn't notice any difference (on an SC or later car). I'd defy anyone to tell if one was actually fitted on a blind road test. On track it might give you a tenth of a second per lap if you were being optimistic.

lboase

120 posts

122 months

Wednesday 20th August 2014
quotequote all
H&R ARB's are a good addition to a C4 to neutralize understeer.

My C4 has H&R springs and refreshed OEM dampers which is a good combo if you're interested in a fast road setup

Blib

Original Poster:

43,975 posts

197 months

Thursday 21st August 2014
quotequote all
shoestring7 said:
If you're looking for a decent ride I'd suggest the Koni FSD system. It has two speed operation that gives a nice ride but still decent body control. Its good value too leaving budget for a refresh of all the bushes (use standard Porsche stuff), top mounts etc. as well as a proper geo job.

http://www.demon-tweeks.co.uk/performance/shock-ab...

SS7
Some more relevant experience here: http://www.pistonheads.com/gassing/topic.asp?t=109...


Edited by shoestring7 on Wednesday 20th August 21:43
These seem to be just what I'm looking for. Thanks for that, shoestring, & thanks to for the link to the thread. thumbup

Encantada

3,975 posts

253 months

Thursday 21st August 2014
quotequote all
Blib.

Be aware that the koni stuff uses standard springs, if you are thinking of reusing yours the rears will have suffered some heat sag over the years....

Kevin.


Blib

Original Poster:

43,975 posts

197 months

Thursday 21st August 2014
quotequote all
Encantada said:
Blib.

Be aware that the koni stuff uses standard springs, if you are thinking of reusing yours the rears will have suffered some heat sag over the years....

Kevin.
Thanks for the heads up. I've had a discussion with the guys at Design 911. They reckon that KONI FSDs with H&R lowering springs would be a good choice for my car.

However, I'm concerned that by going for a lower stance, I'm going to negate the benefits of the Konis.

As I said in my OP, suspension really is quite confusing for a Porsche newbie such as me. frown


ETA: This 'sag' would also explain the slight 'nose up' stance that I recently noticed.

Edited by Blib on Thursday 21st August 18:15