Shock springs options
 

Hi y'all,
I'm looking for help in finding some shock springs that are a little stiffer than the MST 45mm shock springs hard (silver) (part # 210529). I'm actually using them in a Tamiya CC-01 because they fit the Tamiya shocks nicely. The only thing is even the hard springs don't support my vehicle well because the car has been modified and weighs a little more than normal, particularly the front end. Any one here has a need to go with a little stiffer springs in their CFX or CMX ride? What are some other spring options out there? Thanks in advance