I just installed some Flt-tar and discovered they were pretty stiff. I did some research and found out i can buy some helper springs to help the stiffness. i was wondering if anyone else has this set up.

http://www.evasivemotorsports.com/Me..._HELPER_SPRING

i was also wondering whats the difference between

I.D. - Height (mm) 62mm - 50mm
Spring Rate 1.6kg/mm

I.D. - Height (mm) 62mm - 80mm
Spring Rate 2.1kg/mm

Which one would be better to improve ride quality?

ONE LAST THING.. adjustable endlinks should fix the problem to the rattle/creeking noise in the rear?

THANKS IN ADVANCE!!