To have the schocks best matched for any car having a modified suspension (such as extremely stiff suspension), its best to request the shock manufacturer to re-valv the internal presures so to match the stiffness of the springs. Typically, the shocks are made to a predetermined internal pressure that would be acceptable to most average car's suspension stiffness. I've talked with different shock tech reps and they've all suggested that to best fit my suspension setup (very stiff) to have the internal pressure changed by the company. In other words, I wouldn't take an "off the shelf" shock if I wanted best results.