I am sorry, but a rate of 150 Lb/Inch linear just does NOT make sense to me. Here is a basic calculation:

Weight of the turbo is just about 3,600 Lbs
It's about 40/60% F/R weight distribution
That means 2,160 Lbs on the rear two wheels
1,440 Lbs on the front wheels (i.e., 720 Lbs on each front wheel)

With a 150 Lb/Inch spring, that means the front springs compress by 4.8 inches when the car is put on the ground.

What am I missing?

 

Yup, it doesn't make sense and you're not missing anything. I'm not too worked up about it any more as I put in new stiffer springs and monoball top hats. My original intent was just to warn OP that he may potentially run into the same problems as I did.

 

Phew, all is good in 512BB land again

Cheers.

 

What a joke this is. Just subscribing to the thread.

I had a similar problem with a coil over suspension before. When it was lowered, the car had about 1 inch before it hit the bump stop! It was basically riding on the bump stops and road like sht. I cut one inch from the bump stop and miraculously, I had suspension again! Lower springs really don't work without integrated shocks that are shorter so there is actually some travel. Somehow, hearing about another half assed design doesnt surprise me.

 

To be fair to KW the problem could be remedied easily - changing to stiffer spring. (Changing spring is really no big deal and the ability to change springs is among the very reasons that coilover is more advantageous than lowering springs, the flexibility.) It is the support that might not have been perfect, but that could be improved easily. Ok maybe the spring rates are weird too. But bottome line it is not an inherent design flaw, just a matter of which springs. KW is an excellent and competent company.

As for the HLS kit, IMHO to include it in such a performance oriented suspension as the KW V3 is just very very slightly odd but we'll have to wait for users' reports. It would be fascinating to compare HLS vs. non HLS but don't think that's coming any time soon. I do agree that between the 2, it's the HLS that might have made some compromise performance wise.

This issue does illustrate that the KW V3 is not a simple suspension for beginner; it is most definitely not plug-and-play. You have to have a good and experienced setup man that could suggest spring rate and adjust bump and rebound damping to taste, while maintaining handling (this is a lot more difficult than it sounds). Lastly, the KW spring rates of 400/740 implies to me it is (all things considered, etc.) a bit stiff for street driving and is much more a more track oriented setup than Bilstein Damptronic, with its 336/560 springs. This is consistent with the few notes from users that I've seen.
Really interesting thread with lots of good information.

 

Agreed.
However, the point of CO to me is not the ability to change springs, the advantage is to adjust ride height. Or you might as well swap in fixed springs. The other advantage SHOULD be matched shocks with different springs. Nothing to do with dampening, which should be adjustable - it is about ride height. If the CO shock bodies are not shorter to match the range of the CO, then the whole set is useless. You lower the car and end up riding on the bump stops. To have a "dedicated" setup with those spring rates? I really wonder.
I'm not that familiar with KW for Porsche, but typically the Stage 3 variant is a more track than street choice, so the very stiff rear spring is not a surprise. I wonder what front rates are used in the V1 or V2???