suspension help

good day,
have a set of JIC coilover for my cefiro A31, they came from sylvia S13s. problem is, the spring rate doesnt match the cefiro since the cefiro has bigger body and heavier engine. i have rb25det in it.
i like the set-up to be street and tracks

if anyone can help me set-up my suspension?
any help would be appreciated

thanks

JIC is too stiff for street and track. Originally it was thought I had JIC coilovers in the GTR, when I took it to the suspension experts they mentioned that pretty much everyone with JIC suspension has it revalved to soften it up a little because it is too hard, which is not good for street or track, only drift.

Can't help you with the rest but would recommend taking the car to somewhere that really knows their stuff when it comes to suspension, and go somewhere that have their own track cars / employees have similar interests to you. It really, really helps.

does any one know what the spring rate of thier coilover suspension of thier R33 4door sedan with rb25det?