Currently i have jdm itr shocks & springs, LCAs,sway bar and i want to upgrade to GC & koni yellows should i get the itr spec or gsr spec? i think there different not positive please help me out thanks in advance.

 

i would recommend to go with the ITR set up for the rear lower control arm, which are different from the gsr, either than the rear lca's the spring rate should work with your current set up of sway bars.

 

Since you're already using the ITR rear lower control arms, you're going to need to use ITR-specific rear dampers.