993 Suspension Refresh

[Gordo997]

Looks like I need new front shocks for my 993 C2 and seen as the rears are 9 years old I was thinking I may as well change all the shocks and springs (they're original). Car has done ~70k miles but has been kept in a carcoon and the bushes are fine so not planning on changing anything else at this stage. So was wondering if anyone has done something similar recently as it looks like some of the available options have maybe changed since previous posts on the subject?

The car is currently on standard springs rather than M030 or M033 options. Preference would have been to retain this ride height and not go for sports suspension because the roads where I live are terrible so the thought of a harsher set up doesn't really appeal. That said, I understand the M033 springs just lower the car slightly but without being stiffer so would be willing to look at those.


Options seem to be as follows;

1. Porsche OEM replacement springs & shocks from local main dealer - quoted £3050 for parts alone! Think these are the updated "classic" springs as made by Bilstein rather than the old Monroe shocks so perhaps worth thinking about but seem very expensive - see this link https://www.youtube.com/watch?v=WzFouAf9RB4

2. Porsche OEM sports suspension kit inc M030 springs for £1799 from porscheshop.co.uk (looks like the old Monroe shocks from their website picture)

3. Bilstein B6 HD shocks with M030 or M033 springs - approx. £1400 but sounds as though these give quite a harsh ride which I'm keen to avoid.

4. Koni Active (updated Koni FSD shocks) plus M033 springs from Carnewal - approx. 1300 Euro - these seem to have the most favourable compromise for what I'm looking for but was wondering if anyone else has had them fitted and how happy they are or not?

Thanks in advance!

[phib]

I can help a little bit, I have a C4 and a C2.

Bit of a long story but ....

I have been looking to replace the suspension on the C4, at present (as I bought it) it has factory mo30 suspension which then the last owner replaced the front shocks ( about 300 miles ago) with bilstein b6’s hd’s ( silver ones)

However if you want lowered suspension you need b8’s. So basically he fitted the wrong ones ! There’s a £700 mistake !

So I have higher suspension at the front than the back.

So after much research I am planning on changing that to bilstein ps10’s which is a fully adjustable set up. For a more sporty and the right ride height.

On the c2 it’s had new bilsteins b6 ( from memory) it’s ride is excellent and as they were when they came out of the factory (from memory)

If I was doing the c2 again I would go for bilstein b6 hd’s With standard springs which is probably the best compromise in my view for what it’s worth

Phib

Edited by phib on Sunday 19th May 21:09

[Gordo997]

Thanks for that and interesting re the B6’s. A few places seem to sell them as part of a package with the M030 springs so perhaps they can be adjusted to fit both standard and sports set ups? Will look into it.
e.g. https://type911shop.co.uk/epages/de867ca1-377e-432...

[phib]

Gordo997 said:

Thanks for that and interesting re the B6’s. A few places seem to sell them as part of a package with the M030 springs so perhaps they can be adjusted to fit both standard and sports set ups? Will look into it.
e.g. https://type911shop.co.uk/epages/de867ca1-377e-432...

99% sure (although not an expert) they cant out of the box.

I spent about 2 hours with the bilstein technical team working through this, the only work around is to have the thread on the outside of the shock extended to give a lower reach.

The conclusion is that they have to extend the thread by 15mm i belive it has 30mm adjustment from stock

Currently mine has 154mm at the front on the b6's lowest setting and 127 at the back.

...............Front......Rear
Standard.....154.......147
M030..........144.......127
RS..............124.......107

However Bilstein are not sure that this will be possible but will try.

I am sure most people wouldnt notice this but its driving me mad !!

Phib

[R0B3RT]

i'm also going through the same process. I have a 993 1996 C2. Anyway, I bought koni sport active with the intention to re-use my exisiting springs (M033) and top mounts. I have various quotes ranging from £500 for the labour (porsche indie) and £2k for full setup (well known suspension/tuning company) and then £5k from a porsche dealer. Essentally I think I'll go with my Porsche indi and add some contigency for extras that come up - like the front top mounts!

[Ragatha christie]

I recently put brand new PSS10, RS topmonts, and every worn bush has been replace and car feels like its brand new. best upgrade I have ever done

[C4ME]

phib said:

Gordo997 said:

Thanks for that and interesting re the B6’s. A few places seem to sell them as part of a package with the M030 springs so perhaps they can be adjusted to fit both standard and sports set ups? Will look into it.
e.g. https://type911shop.co.uk/epages/de867ca1-377e-432...

99% sure (although not an expert) they cant out of the box.

I spent about 2 hours with the bilstein technical team working through this, the only work around is to have the thread on the outside of the shock extended to give a lower reach.

The conclusion is that they have to extend the thread by 15mm i belive it has 30mm adjustment from stock

Currently mine has 154mm at the front on the b6's lowest setting and 127 at the back.

...............Front......Rear
Standard.....154.......147
M030..........144.......127
RS..............124.......107

However Bilstein are not sure that this will be possible but will try.

I am sure most people wouldnt notice this but its driving me mad !!

Phib

My understanding of the Bilstein B6 is as follows with 3 options

1/ Bilstein B6. For standard suspension height.
2/ Bilstien B8. A shorter shock tube for use with lowered springs (M030, M033, etc).
3/ Modified Bilstein B6 with extended thread. For use with standard or lowered springs. Supplied by companies such as Carnewal (they call them B6XT for extra thread). Not something you can buy from Bilstein so assume Gert has some sort of arrangement to have them manufactured or modified.

B6 and B8 are both valved the same, so identical damping forces, it is just that the shock tube length is shorter on the B8. What is unclear on the B6 extra thread type shocks is whether there is ever a problem with the shocks bottoming out on the 993 when running a lowered ride height (because they will physically bottom out earlier due to the longer tube length). Before the B8 was available the B6 extra thread was the only way to get the B6 low enough hence why this modification existed. If I was buying Bilstein for lowered suspension I would buy the B8 unless someone could convince me the B6 extra thread is not compromised at lower ride heights (I don't have a feel either way for if it is or not).

Edited by C4ME on Thursday 13th June 17:01

[phib]

C4ME said:

My understanding of the Bilstein B6 is as follows with 3 options

1/ Bilstein B6. For standard suspension height.
2/ Bilstien B8. A shorter shock tube for use with lowered springs (M030, M033, etc).
3/ Modified Bilstein B6 with extended thread. For use with standard or lowered springs. Supplied by companies such as Carnewal (they call them B6XT for extra thread). Not something you can buy from Bilstein so assume Gert has some sort of arrangement to have them manufactured or modified.

B6 and B8 are both valved the same, so identical damping forces, it is just that the shock tube length is shorter on the B8. What is unclear on the B6 extra thread type shocks is whether there is ever a problem with the shocks bottoming out on the 993 when running a lowered ride height (because they will physically bottom out earlier due to the longer tube length). Before the B8 was available the B6 extra thread was the only way to get the B6 low enough hence why this modification existed. If I was buying Bilstein for lowered suspension I would buy the B8 unless someone could convince me the B6 extra thread is not compromised at lower ride heights (I don't have a feel either way for if it is or not).

Edited by C4ME on Thursday 13th June 17:01

From what I have found out thats 90% correct, the first photo is my 993 with mo30 kit but with the b6 xt's on the front and standards on the back. Basically you cant get the xt's low enough to match the rears.

The 2nd photo is now bilstein have taken my xt's and added 20mm thread to the existing thread, they haddnt done this for anyone in the UK and werent sure if they could do it but it has worked so now bilstein b6xxt's. (this was done yesterday) The challenge was holding the shock whilst cutting it.

Having it set up at the moment so will see how it is.

It never bottomed out with the standard xt's

bear baby is called

Edited by phib on Thursday 13th June 20:59

[C4ME]

phib said:

From what I have found out thats 90% correct, the first photo is my 993 with mo30 kit but with the b6 xt's on the front and standards on the back. Basically you cant get the xt's low enough to match the rears.

The 2nd photo is now bilstein have taken my xt's and added 20mm thread to the existing thread, they haddnt done this for anyone in the UK and werent sure if they could do it but it has worked so now bilstein b6xxt's. (this was done yesterday) The challenge was holding the shock whilst cutting it.

Having it set up at the moment so will see how it is.

It never bottomed out with the standard xt's

What ride height are you trying to run, M030, RS or RS+10? I used to run M030 with the Carnewal extra thread fronts and I am 99% my 993 was set to M030 ride heights OK. I can check with my indi if he still has the ride heights written down in my file if you want.

Edited by C4ME on Friday 14th June 03:31

[phib]

Thanks, I am just trying to run M030 ..... which shouldn’t be that hard !!

Phib

[Kananga]

I recently had a full suspension refresh on my 993 C2. Koni/M030, along with every other component.

I find the ride and handling is perfect for UK roads: sporty but not too harsh. Admittedly I have no plans to track the car, but just mention in case anyone is on the fence.

[phib]

C4ME said:

What ride height are you trying to run, M030, RS or RS+10? I used to run M030 with the Carnewal extra thread fronts and I am 99% my 993 was set to M030 ride heights OK. I can check with my indi if he still has the ride heights written down in my file if you want.

Edited by C4ME on Friday 14th June 03:31

Just for info

First photo ( mo30 springs and bilstein xt's on the front)

Front 152
Rear 127

2nd photo (mo30 springs and bilstein now we will call them xxt's of front)

Front 140
Rear 127

The fronts will go back up a bit today to 144 so should be correct for MO30

Phib

[C4ME]

phib said:

Thanks, I am just trying to run M030 ..... which shouldn’t be that hard !!

Phib

No it shouldn't be!

I trawled through my emails and dug out some stuff. The shocks were bought in 2007 from Gert at Carnewal and they were called Bilstein HD in those days and I got the ones with the extra thread (HDXT). Everything I have read says that the HD were the B6 before the B8 existed and the range was rebranded. The car was set to RS ride heights when they were installed. The car then had the ride height raised six months later to close to M030 (minus 10 at front) at Center Gravity.

Looking at his before and after report

Before: 125mm front, 110mm rear. This confirmed it had been running at RS height.
After: 135mm front, 130mm rear. The objective was based on M030 but with 9mm lower at front and 3mm up at rear as wanted more of a rear to front rake.

Both of those are below what you are trying to achieve at the front. Other than the Bilstien shocks the suspension was completely factory standard so standard top mounts, standard hub carrier etc.

Where did you buy your B6XT from?

Edited by C4ME on Friday 14th June 12:39

[phib]

Thanks for the info, yours sound very adjustable the b6 xt’s Don’t have anywhere near that adjustment.

The ps10’s do though

Unfortunately the previous owner bought them about a year ago.

Bad photo but there was little adjustment on them

https://www.design911.co.uk/mobile/#part;id=3135

[C4ME]

phib said:

Thanks for the info, yours sound very adjustable the b6 xt’s Don’t have anywhere near that adjustment.

The ps10’s do though

Unfortunately the previous owner bought them about a year ago.

Bad photo but there was little adjustment on them

https://www.design911.co.uk/mobile/#part;id=3135

Perhaps they were standard B6 rather than the ones with the B6XT extra thread. Here is what B6XT look like, not a great picture but shows the longer threaded area http://www.carnewal.com/products/993/p93089/Bilste...

Sounds like you have the solution though by having yours modified. Bilstein are always really helpful in that way.

Edited by C4ME on Friday 14th June 13:58

[phib]

C4ME said:

Perhaps they were standard B6 rather than the ones with the B6XT extra thread. Here is what B6XT look like, not a great picture but shows the longer threaded area http://www.carnewal.com/products/993/p93089/Bilste...

Sounds like you have the solution though by having yours modified. Bilstein are always really helpful in that way.

Edited by C4ME on Friday 14th June 13:58

Thanks, this all makes sense now I think.

Mine now look like the ones in the picture, previously they were b6 sports but with xt written on them !!!

Probably where all the confusion came from !!!!

https://www.bilsteinsuspensionstore.co.uk/bilstein...

Blooming confusing !!

Thanks

Phib

[Gordo997]

Thanks for al the replies and feedback. Have decided to go for the Koni Actives with replacement standard springs from Porsche as I’d prefer to keep the car at the original ride height.

[996GT3Trev]

The Koni's are a great replacement damper, I have the Koni FSD's with M033 springs and it feels fantastic on the road. The key is to have it set-up right, I went to CoG.

Trev