I m planning on getting some TEIN (maybe D2) coilovers, but I m torn if the extra $200 is worth it for the SS-P setup. I m also torn on whether the 7/4 setup is right for me.

Does anyone have any experience with how much of an advantage,if any, the pillowball knuckles have on launch? Logically it seems that the effect should be minimal as the spring will resist the engines upward motion, not the damper, and the spring is firmly attached regardless of the setup.

Also, what difference would a 7kg/mm vs 10kg/mm spring make on launch. Can someone with experience on the track weight in. Any appreciable 0-60ft difference?