Most of Swift 10" and longer springs (Excluding the drag racing springs and Conventional springs) are Barrel Design; the design is to solve all spring deflection (bowing) problems. With bowing springs, you can expect spring rate inconsistency, and rubbing against the shock body that would lead to damage on the shock adjusting perch thread.
One approach to assess spring deflection would be to increase the number of coils on the springs. With more coils on the spring, you will experience less bowing motion. This is the easy and cheaper method to solve the issue. But the downside of this method is a decrease in spring stroke, increase in un-sprung mass, and will affect the overall movement of other suspension components.
