//steve\\

I'm trying to find out how many if anyone at all is running 550lb springs on the Koni yellow/GC coilover setup. I was actually looking at the complete coilover kit from Ground Control and it's basically the same except it has their own tops instead of reusing the factory mounts. You can get them with 380, 440, or 550lb springs. On my previous s2k I ran springs a little over 650lbs and had no issues with them and while they could be a tad harsh at times they were more than livable. That was also running cheaper coilovers not something with a shock as nice as a Koni yellow.

I know the 550lb springs are at the very top limit of what the yellows can support but have people run them and found even daily driving they aren't so bad?

I would honestly love to just buy a set of KW V3's but at almost $2000 it's harder to justify. GC sells their complete coilover at $1300 which seems to be a great deal for what you get.

I'm just looking for some input from people that have run similar setups

BowlofRice

I have the Koni Yellow/GC combo with 550/431 springs. I daily drive in burbs of Seattle with 1 full turn from soft on the Koni's. The harshness is very tolerable as it rides close to stock with only the bumps being more jarring due to the increased spring rate. Keep in mind that this subject is very subjective, hope that helps.

dan_uk

On the track I ran 700/600 and it was a bit too much for the shocks to cope with so I went to 600/500 which was better.
I think you are right on the limit with 550 of what the shocks can handle but should be ok

One thing I noticed is when I set rebound to 2 turns (basically full) the car felt like it was "jacking down".
Even though the shocks should have been well out of range for the springs I felt best with 1 1/2 turns of rebound ish.
Don't assume cos you are at the limit you should just whack rebound up to max

scareyourpassenger

The adjustments on most shocks are not linear.. I know someone running 550 on the front and 500 rear with great success as well. Going above that will just make the ride harsh and reduce overall grip.