Maybe i wasn't enought clear. My goal with this post wasn't to improve handling but restore ride quality (it's why my post is in maintenance rather than upgrades). The feeling and handling I have now are very silimar as I bought the car (and before the 2 rear springs broke...) but with a little more stability from the rear end. The last change (passing the 9,5 to 9,9) is about improving confort lost with the stifness upgrade (of 10-15 %). 10 is a SHO with all his original working SARC suspension.