Hi JH6.
I know all about the difficulties of finding any solid information on the SPAX suspension.
That's why I decided to try it out, given the fact that it's soo much cheaper than KW and Koni and the lot.
When I bought them, design911 had a campaign, so I paid £499 and figured I'd give them a go.
My experiences over the last 4 months have been very positive.
Before I give any advice I must say that I have also replaced the original sway bars with M030s and installed delrin-bushings together with Racers Edge mounts.
The front strut "towers" were shot and have been replaced with Racers Edge camber plates. And the front rear castor blocks have been replaced with Elephant Racing solid monoball blocks. (not to happy with them though)
So my car isn't so stock when it comes to suspension anymore.
Anyway, here goes..
Pros:
- They are super easy when it comes to adjusting the stiffness. No jacking of car, just turn the knobs and voila!: instant race car or daily cruiser.
- They are cheap and haven't shown any signs of weakness yet.
Cons:
- They don't have brackets for the brake cooling ducts installed on the front dampers.
You'll have to spot weld the brackets from your old dampers to them if you want them. (I left them out)
- The rear dampers are somewhat narrower in the bottom mounting than the originals. Meaning that you might have to change to shorter bolts or get hold of some suitable spacers.
- I don't know the stiffness of the front springs. They are stiffer than the originals. but I can't say how much. They seem to be a good all round substitute though.
My verdict is that if you are like me, and want to use your car for both normal driving but also track days and some occasional slalom runs, this is an adequate upgrade and I'm happy.
But if you're a track junkie, you would probably be happier with something bigger and more expensive.
Hope this was helpful.
Best Regards, Tor