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Porsche 993 suspension rebuild

Porsche 993 suspension rebuild

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Wozy68

Original Poster:

4,464 posts

92 months

Tuesday 25th August 2015
quotequote all
I know I have already posted this before, but now its complete I thought I'd repost with a heading that may be easier found in years to come for those who wish to know what is involved and the costs.

I started down this road when OPC Swindon informed me in 2014 the front damper top mounts were shot. It became very much a 'Whilst your in there' follow on from that, and I ended up replacing not only top mounts all round, but also new dampers and all the ARB bushes and drop links. I came to the conclusion that the old girl had had 20 years of use covered 125K miles and it really was time for a refurb. However when I got her back I wasn't that impressed. Basically replacing only certain parts of the suspension with new, showed up the wobbly worn and old rest of it..

I'd assume if installed at any well known Indie and paying garage supplied parts this little refurb would cost near £9K maybe a little more for the complete suspension replacement and to include final GEO setup at somewhere like Center Gravity. I managed to do it all in for around £7000.00,

I believe I saved at least £1800.00 - £2000.00 by sourcing the parts myself and having reburbished front wishbones and lower rear suspension control arms as I couldnt source new ones that were not silly money. I just could not warrant spending around £1K for new OPC supplied front wishbones. Everything else is brand spanking new. I also saved a fortune by getting a local 911 owning Porsche nut mechanic to install it.

I had it all replaced over 12 months in two stages, firstly as stated above because the rest of it felt worn out after installing the initial parts and secondly funds or should I say lack of them.

So these arrived, complete with new M033 springs top mounts etc etc and were fitted in June 2014.



OPC pointed out further suspension wear when she was serviced this year, and that forced the issue.

So this little lot was sourced. Ladies and Gentlemen; the complete suspension components for a 993 C2, ready for fitting. July 2015.



Installed, some lovely nice shiny bits.


















Costs individual

2014
FSD dampers £744.00
M033 springs £399.00
Front & rear ARB bushes and drop links x 4 £725.92 - Cost supplied by Indy
Top mounts x 4 £675.00
Various bits and pieces, bump stops and damper rubbers etc £60
Install and GEO £720.00

2015
Rear suspension upper control arms front £194.50 per pair
Rear suspension upper control arms rear £258.60 per pair
Rear suspension lower rear control arms £192.00 (Hartech reburb) per pair
Rear suspension 'A frame' track control arm £603.20 per pair

Front suspension wishbones £324.00 (Hartech refurb) per pair
Front suspension wishbone balljoints £149.60 per pair
Front trackrod ends £219.98 per pair

Install of the above (I got it heavily discounted because I know the fella) of £1080.00 which included install of new set of ignition leads so that evens it up.

Plus .....

Geo @ Center Gravity £567.00 (Estimated) - Actual cost £435.00

C&G are great people, really nice and know their stuff. Highly recommend.

Things to remember and this is important.

Prices vary wildly for OE TRW suspension components. I sourced a lot of mine from Europe and especially Germany as UK prices were madness. For example for the rear suspension upper rear control arms, the cheapest I could find them in the UK at the time was £468.60 per pair. I eventually got them from Germany for £228.00 per pair delivered.

I've been informed that Porsche are clamping down on TRW supplying parts in the UK (No idea if this is happening anywhere else in Europe) to third party suppliers and forcing a lot of parts to be sold only through the Porsche network or at least with Porsche 'tax' added. So if you are thinking of a suspension refurb on your 993 start purchasing now, and search hard for the parts. C&G confirmed whilst having the GEO done that it is now very difficult to get OE parts from third party suppliers other than OPC or Porsche supplied to Indie Porsche suppliers, this means Porsche Tax on everything, and Porsche Tax is very expensive..

Refurb rear suspension rear lower control arms was due to supply shortage. I just couldnt get them in a reasonable time frame without spending silly amounts from either the well known UK Porsche suppliers or Porsche themselves.

In the end, what really surprised me is that Porsche OPC or Porsche parts sellers differ little in price on a lot of Porsche branded parts.
The biggest surprise though is just how wide the gap is on component prices from different suppliers in different countries. Absolutly gobsmacking ... Do your research is all I can say.

As I have said above, the old girl had done 125K miles when the dampers, springs, drop links etc were replaced and previous to that only an offside front balljoint had worn out, the rest of the suspension 12 months and around 5000 miles later. She had a gentle owner before me, so I'm hoping she wil require nothing suspension wise for at least another 60K miles. C&G actually thought if used regulary she should last 100K miles plus (excluding the dampers).

Results?

The car feels so much calmer, looking down at the speedo you suddenly realise just how much faster the car is travelling. The greatest change is in the steering though, absolutly fantastic. No more tramlining, moving from one side of the road to the other, very direct now the wishbones have been sorted and the car feels very planted front and rear. On underlating roads, she just steers straight without wanting to head towards the nearest ditch, ie no more having to fight the wheel to keep her going where you want her to go.

I can't emphasize enough just how good the steering is, total change. C&G also checked the steering rack for wear and play, there was none which was a relief and says a lot about the quality of Porsche parts at that time. They actually complimented the car underneath stating she was in very good overall condition, which was nice to hear after spending so much dosh on her.

I was worried that this was all going to be a waste of money, that I wouldn't feel the difference. Basically I have a brand new car under the bodywork and thankfuly you can tell. She just feels so much tighter and together, though I sometimes feel a little too soft maybe ....... well that's untill I drive down one of our usual A&B country roads, then it all makes sense. You can feel the grip more at the rear, and the front now just gently bobs along and you feel everything the front wheels are doing as per a 911 should.

I have learnt so much from this excercise and one of the most important is that potential 993 enhusiasts (note I say enthusiast rather than invester) should not worry so much about mileage and rear chassis leg rot. This side of an engine rebuild or possibly a glass out respray, the suspension components on the 993 are far far more expensive and far more important. A worn out 993 is not a nice drive.

Center Gravity told me stories (and they see around two 993s a week) of much lower mileage 993s that were in a poor state with worn and rusty suspension ....... So mileage it seems means little in real life and could save you a wedge on the cars purchase cost.

Right then, on to the next project. Just how much is it going to cost me to install a LWF & clutch. wink


Edited by Wozy68 on Friday 4th September 12:32

ash73

13,798 posts

143 months

Tuesday 25th August 2015
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Good grief, glad I got shot of mine! Hope you enjoy it though after the mods.

YoungMD

285 posts

42 months

Tuesday 25th August 2015
quotequote all
Nice article and v helpful, sourcing parts in Europe is certainly a good idea. Just a question, Could you not do the fitting yourself, never done one on a 993 but generally suspension just requires some muscle and all is well, then can pay to get it set up probably and they generally check all the suspension etc so you have comfort all is good.

Funny but all you hear about 993's are the great engines and then people assume they will be cheap to run, great cars but not cheap porsches to run

mark.c

985 posts

102 months

Wednesday 26th August 2015
quotequote all
Great news Wozy, and thanks for posting too. I went through a similar process a couple of years back with my Turbo, I didn't have to change as many arms as they weren't required and I fitted it myself but the cost still spiralled very quickly ! It could probably do with another geo check again now I think about it .

I've done the LWF thing on a 964C2 and loved it, also did it on the Turbo and although the biting point is a bit higher I'm glad I did it. ( if nothing else to know that I won't have to replace the flywheel again ) . I can't quite put my finger on it though, engine characteristics perhaps but I think the LWF suited the NA car better.

Enjoy your new set up thumbup


drmark

3,294 posts

108 months

Wednesday 26th August 2015
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Proper PH thread.
Enjoy smile
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roygarth

2,559 posts

170 months

Wednesday 26th August 2015
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Thanks for that!

g7jhp

5,153 posts

160 months

Wednesday 26th August 2015
quotequote all
Wozy68 said:
Right then, on to the next project. Just how much is it going to cost me to install a LWF & clutch. wink
Great write up Wozy68.

I'd think carefully about a LWF and clutch, you may want to try one if possible as although some of these mods are great for weekend only they make the car harder to live with day to day. Just a consideration. Look forward to the next installment! smile

ras62

856 posts

78 months

Wednesday 26th August 2015
quotequote all
It looks like the rear shocks don't have any height adjustment but the front shocks do? Were the corner weights done by CG?

wfarrell

212 posts

142 months

Wednesday 26th August 2015
quotequote all
g7jhp said:
Wozy68 said:
Right then, on to the next project. Just how much is it going to cost me to install a LWF & clutch. wink
Great write up Wozy68.

I'd think carefully about a LWF and clutch, you may want to try one if possible as although some of these mods are great for weekend only they make the car harder to live with day to day. Just a consideration. Look forward to the next installment! smile
...recommend addling an MPL clutch slave cylinder with LWF & RS clutch ...improves low speed drivability and pull-away control with the lower mass flywheel (also compliments short-shift mod etc)

cheers, Will

Wozy68

Original Poster:

4,464 posts

92 months

Wednesday 26th August 2015
quotequote all
ras62 said:
It looks like the rear shocks don't have any height adjustment but the front shocks do? Were the corner weights done by CG?
Car didn't require corner weight adjustment by all accounts as when checked it was spot on for M033s, hence why the invoice was less than the estimate.

Edited by Wozy68 on Wednesday 26th August 18:28

Wozy68

Original Poster:

4,464 posts

92 months

Wednesday 26th August 2015
quotequote all
wfarrell said:
g7jhp said:
Wozy68 said:
Right then, on to the next project. Just how much is it going to cost me to install a LWF & clutch. wink
Great write up Wozy68.

I'd think carefully about a LWF and clutch, you may want to try one if possible as although some of these mods are great for weekend only they make the car harder to live with day to day. Just a consideration. Look forward to the next installment! smile
...recommend addling an MPL clutch slave cylinder with LWF & RS clutch ...improves low speed drivability and pull-away control with the lower mass flywheel (also compliments short-shift mod etc)

cheers, Will
I hear what your saying, I was thinking of installing one even if I went for a standard FW/Clutch as I have dodgy left ankle smile

Wozy68

Original Poster:

4,464 posts

92 months

Wednesday 26th August 2015
quotequote all
YoungMD said:
Nice article and v helpful, sourcing parts in Europe is certainly a good idea. Just a question, Could you not do the fitting yourself, never done one on a 993 but generally suspension just requires some muscle and all is well, then can pay to get it set up probably and they generally check all the suspension etc so you have comfort all is good.
I did have a thought of having a go at it, but I havent a lift and was worried if it didnt all come apart easily enough I'd be stumped with just a pair of wobbly axle stands. As it was at least one of the rear control arms had to be cut off as the bolts had seized.

Also you have to tighten everything when the cars weight is on its wheels, not suspended and I couldnt see how I could have tightened it all up with the car on the floor.


Wozy68

Original Poster:

4,464 posts

92 months

Wednesday 26th August 2015
quotequote all
g7jhp said:
Wozy68 said:
Right then, on to the next project. Just how much is it going to cost me to install a LWF & clutch. wink
Great write up Wozy68.

I'd think carefully about a LWF and clutch, you may want to try one if possible as although some of these mods are great for weekend only they make the car harder to live with day to day. Just a consideration. Look forward to the next installment! smile
Thanks. I've owned the LWF etc for around two years, and the boat is still out whether I install it or not. I've heard good and bad, so I'm still not sure which way to go. The outcome seems to differ from one car to another.

YoungMD

285 posts

42 months

Wednesday 26th August 2015
quotequote all
Wozy68 said:
YoungMD said:
Nice article and v helpful, sourcing parts in Europe is certainly a good idea. Just a question, Could you not do the fitting yourself, never done one on a 993 but generally suspension just requires some muscle and all is well, then can pay to get it set up probably and they generally check all the suspension etc so you have comfort all is good.
I did have a thought of having a go at it, but I havent a lift and was worried if it didnt all come apart easily enough I'd be stumped with just a pair of wobbly axle stands. As it was at least one of the rear control arms had to be cut off as the bolts had seized.

Also you have to tighten everything when the cars weight is on its wheels, not suspended and I couldnt see how I could have tightened it all up with the car on the floor.
A few ramps, amazing what you can afford out of the labour savings, I always figure if the worst comes to it I can always call out one of these mobile mechanics to fix it up and get it to an Indy should the worst happen.

I tackled my 4x4 suspension before the summer thinking I probably wouldn't get far, but with a few days and lots of that spray stuff it all came off, I think the issue is it needs not to be your only daily drive, or else it all gets a bit of a rush. I have always found Porsche to be easier than other cars to work on, more complicated but much nicer put together, the water cooled one have some engineering you would expect to find on a ford, but mostly they too are good too in my humble view

ras62

856 posts

78 months

Wednesday 26th August 2015
quotequote all
Wozy68 said:
ras62 said:
It looks like the rear shocks don't have any height adjustment but the front shocks do? Were the corner weights done by CG?
Car didn't require corner weight adjustment by all accounts as when checked it was spot on for M033s, hence why the invoice was less than the estimate.

Edited by Wozy68 on Wednesday 26th August 18:28
Without rear height adjustment corner weighting is not really possible, it has nothing to do with what springs are used. M033 springs with original dampers would have allowed corner weighting. It sounds like this Koni set up is quite compromised for use on the 911.

cmoose

39,517 posts

151 months

Wednesday 26th August 2015
quotequote all
Interesting and terrifying in equal measure!

Re TRW, I believe it was bought out by another company recently (forget which) and it may have lost its contract to make Porsche bits in the process or something along those lines.

I think some parts even for quite recent cars (eg front coffin arms for 9x7) are in short supply as a consequence, even within the Porsche empire so we may be in a transitional period before the new supplier kicks in. I guess nobody makes pattern parts for the 993?

Re bush wear, I struggle to get my head around the idea that not using the car makes rubber bushes etc wear out faster. How does this work? They're not oiled, so how do heat cycles, greater exposure to elements and physical manipulation of a rubber bush reduce the wear rate?!

Wozy68

Original Poster:

4,464 posts

92 months

Wednesday 26th August 2015
quotequote all
ras62 said:
Without rear height adjustment corner weighting is not really possible, it has nothing to do with what springs are used. M033 springs with original dampers would have allowed corner weighting. It sounds like this Koni set up is quite compromised for use on the 911.
I really have no idea. Koni FSDs seem to be the defaco replacement for the 993 compared to the original Monroes that are still available from Porsche. Interestingly mines is one of the very first RHD 993s in the country and it came fitted with Boges, these are no longer available however.
I have to accept the explaination of Centre Gravity that it didn't require corner weighting as I really have no idea. I'm a woodworker not a suspension guru smile

cmoose

39,517 posts

151 months

Wednesday 26th August 2015
quotequote all
YoungMD said:
I have always found Porsche to be easier than other cars to work on, more complicated but much nicer put together, the water cooled one have some engineering you would expect to find on a ford, but mostly they too are good too in my humble view
I did the suspension on my old 986 (amongst quite a lot of other stuff) and it always struck me the reality of the engineering when you get underneath it was far better than the usual 'water-cooled cars are just Toyotas' refrain.

Even a base 986 Boxster has 100% all-aluminium suspension arms and monobloc brake calipers, just as a for instance. Have a look under a 3 Series BMW or Merc C of the same era (much less a Ford) and you'll find it's all pig iron and pressed steel.

Wozy68

Original Poster:

4,464 posts

92 months

Wednesday 26th August 2015
quotequote all
YoungMD said:
A few ramps, amazing what you can afford out of the labour savings, I always figure if the worst comes to it I can always call out one of these mobile mechanics to fix it up and get it to an Indy should the worst happen.

I tackled my 4x4 suspension before the summer thinking I probably wouldn't get far, but with a few days and lots of that spray stuff it all came off, I think the issue is it needs not to be your only daily drive, or else it all gets a bit of a rush. I have always found Porsche to be easier than other cars to work on, more complicated but much nicer put together, the water cooled one have some engineering you would expect to find on a ford, but mostly they too are good too in my humble view
I do understand this and I drive a defender as a daily so not unused to doing a bit of DIY. smile

However it took around 20 hours just to remove and replace the suspension, and I really didn't want it taking up the summer months struggling with it plus I haven't got halve the kit. Fair play to anyone who installs it themselves though.

Wozy68

Original Poster:

4,464 posts

92 months

Wednesday 26th August 2015
quotequote all
cmoose said:
Interesting and terrifying in equal measure!


Re bush wear, I struggle to get my head around the idea that not using the car makes rubber bushes etc wear out faster. How does this work? They're not oiled, so how do heat cycles, greater exposure to elements and physical manipulation of a rubber bush reduce the wear rate?!
No idea, just something about rubber drying out through lack of use and then it cracking and allowing dirt and grit entering the joints and causing wear. I can only repeat what I was told,

I stated it only because I assume they know what they are talking about. What suprised me most is that they setup on average around two 993s a week, which I was amazed at, I thought originally they meant two a month. I hadn't realised just so many 993s were out there and they had so many coming through their doors.