Suspension upgrade

[Richard Dawson]

Colin Belton has extolled the virtues to me of fitting the GT2 Evo rear subframe mounts. He uses this on his RS to good effect.

Whilst I do not know Colin directly he seems to speak sense. Has anyone any experience of this upgrade? It apparently cures the slight wooliness that can affect 993's at the back and improoves high speed handling.

Secondly and I know this crosses with another post but what tyre recommends are there for Nurburgring use? I currently have SO2s on.

I have thought about a track day tyre such as 48Rs but it is a 1000 mile trip from Bolton to and from the 'Ring including some lappery and I am concerned about tyre wear. I don't want anything on the car that spoils the 993's useful ability to work on the road (unlike the 964!)

Kind regards

 

[roygarth]

I have Dunlop DZO2G (the R1 stickier compound) and drive to and from Spa/Ring with no probs and then have muchu funno on the track! At £750 a set inc. VAT good value too. I'm sure they are crap in wet but I never use car/push it in wet so don't know for sure.

I had SO2's before, the first time out on DZ02 at track was Spa, was giving friend a passenger lap, grip levels were so high compared with SO2 we were laughing our heads off! Seriously, the difference was astonishing.

 

[micksummer]

I've just got a set of Toyo R888 on my RS and managed to do a day in Spa, wet and dry. The grip is good both in wet and dry, as long as there's no standing water. Much better than the SO2 I had on the car before (might well be something to do with the age of the SO2 as well). It'll last pretty well for road + track use, I was told @@6000miles road/track mix. Might not be the grippiest but cheap enough to replace regularly.

 

[zub]

I've got the rear subframe mounts on my RS and so has Rocket123 who sometimes posts here. I find it improves stability under high speed braking, but then again I've had it done a few years ago so can't really describe what it was like beforehand. Maybe Rocket123 will add his 2p worth if he's around....

 

[clubsport]

The denser (mor solid) Gt2 rear subframe mounts work well to eliminate some rear subframe twist at the slight expense of increased harshness and vibration through the car......have ben running Dunlop Do1 for a while now...off to have my toyo888 fitted today

 

[micksummer]

Paul it'll be interesting to see how you compare the 2 tyres. Let us know.
Regarding the subframe mount, is the improvement something that you'll only notice if you're a very competant driver and really know the car, or is it something pretty noticable for a "normal" driver?

 

[clubsport]

Will do, I have driven on 888 before and was impressed.....Mick, you will notice the harshness by changing the subframe mount [] There is definitely some improvement in rear end behaviour,,,I wouldn't rush into it, enjoy the car, get more comfortable with the car on track then maybe try the next mod []

 

[micksummer]

Don't think I'll be doing any more mods to it for a while, the car is way beyond what I can extract from it at the moment, and I feel I'm not even touching it's potential as it is.

 

[paul howells]

The sub frame mounts are agood move,if you are competing,or want a more track focused car,with draw bags as clubsport says,vibration and noise.
I have been running this for a few years now,and do drive to the ring etc,its tolerable.
Also need to inspect the body work steel around these points for cracks starting,they do crack.
Standard is very good also.

 

[micksummer]

ORIGINAL: paul howells

Also need to inspect the body work steel around these points for cracks starting,they do crack.
Standard is very good also.

That sounds like a draw back that's not really worth taking for the small gain, surely, unless as you said, you're racing?

 

[Ninemeister]

ORIGINAL: micksummer
That sounds like a draw back that's not really worth taking for the small gain, surely, unless as you said, you're racing?

In my opinion, it's much more than a small gain - in fact it is the first modification that I recommend for all high power 993's including cabriolets. If you avoid using slicks and crashing over all the kerbs at the track, you should not have chassis cracking problems from the additional stress.

 

[micksummer]

What sort of cost are we talking about here, is it a matter of hundreds, or thousands? Is the standard mount a perishable item, ie is it worth waiting till it's worn out and then replacing with the solid ones, or am I likely to be too old to drive when that happens?

 

[RIVIERAM002]

All these modifications to the 993 rs are new to the likes of me and Mick, who are relatively new to the car,
maybe somebody could compile a top 10 list of ' improvements from standard ' that could be considered,
maybe a small hand book ' the difinitive guide to the 993 rs ' a joint venture between Paul and Colin,
at £25 a book, put my name down for a signed copy !!
confused.com

 

[micksummer]

Yup, I'll sign up for a signed copy as well plz![]
Joking aside, I think I'll mod the weakest link first, which is my driving![] Haven't had any formal "tuition" as such so I might "invest" in one or two of those CarLimit days and a BMW Ring tuition sometime next yr.

 

[paul howells]

The gains are worth while as is said if its a track focused car or your out to get the fastest time.
They do perish and also harden with time.
I would say the first thing is correct set up,tires,and driver education.
Check all joints and bushes for wear,top mounts on the front i have gone through 2 left hand and one right hand in about 8 years.The rose joint can be replaced instead of the complete unit,alot cheaper.
Then dampers and springs along with solid rear mounts,new standard dampers will take some beating
Then you will need more power!!
If you want at some point,we can arrange a day at a track some time,There are plenty of able drivers to lend a hand.

 

[clubsport]

Thing is chaps, for us less able drivers the 993RS is fine straight out of the box....I still learn something everytime I track the car, don't feel the need for any mods as such...as the cars get older and used parts need replacing that is when I seek the opportunity to upgrade......right now diff plates worn,,,,next week motorsport pates going in....will I feel the difference??..doubt it, but should last longer...will just carry on driving and learning...also more fun when you get into the pits at trackdays and you can tell some of the kettle owners the car that went past is 300bhp and totally standard []

 

[micksummer]

Cheers Paul & Paul![]

My car now has a set of R888, geo set up for fast road/track, as for the driver, well, still working on it. I'll grab you if we're in the same trackday next time.

I thought the RS has Uniball solid shock mounts front and rear? Do they wear? Thought there's no moving parts in them?

As far as I know, the RS dampers are Bilstein, so if and when they wear, are they able to re-condition/re-valve them as you could with the aftermarket ones?

Don't think I'll need much more power for a long while yet, but would be nice to have it working as it should. Put the 100 cells cat and Cargraphic mufflers on, simply because they're available at the time, but I don't think it improves the power, if anything it feels that the engine works less well. So I guess a re-map would prob help to optimise the set up.

Other than that, I'll do the mods the same way as you Paul, replace with uprated parts as the original wears out. I guess the next thing to go would be the clutch, and as my German dentist spec RS has the DMF, a LWF would prob be a nice change.

 

[paul howells]

Clubsport,your spot on for normal use and some track days.
I would say however,the motorsport diff plates,you will feel it around the first corner,if you dont there is something wrong!!
Billys you can get serviced,never seem quite as good as new though,they are also a good price from porsche or colin etc
Top mounts are uniball,and do wear,they turn every time you turn the steering wheel,and get a lot of hammer up and down.

 

[Laurence Gibbs]

wrt Bilstein dampers, if they are single tube type they can be rebuilt. Bilstein do not rebuild their twin tube dampers however. At least they did not when i contacted them about it!

 

[Ninemeister]

The price for fitting the stiff axle kit is around £1000+VAT including the kit. My recommendation is to buy new dampers rather than having the originals rebuilt, occasionally the rebuild ones go wrong and then the apparent cost saving is wiped out when you have to pay to have it removed and refitted. My car runs stock Bilsteins and springs, stiff axle kit, ARB's on full hard (most of the time) and around 2 degrees neg camber all round - running over 400hp this is enough to consistently set Speed event records (Brands, Combe, Cadwell, Ty Croes, Goodwood, Harewood, Guston, etc) whilst beating modified GT3RS's into submission.
The bottom line is that you really don't need to spend a fortune to get the best from the 993RS, you just need to get the best from what you have, and the stiff axle kit allows you to do that at the limits of grip and I for one would not want to track my car without it.