INCREASE TRACTION, LESS UN-SPRUNG MASS, MORE STROKE, INCREASED HANDLING. THE ONLY THING YOU WILL BE LOSING IS TRACK TIME.
As you might know, the United States is the largest racer populated country in the world. Through Swift's experiences from extensive testing in world class racing in Europe and Asia, they have great confidence that they can provide the same results in the US. Swift specifically designed a standard measurement race springs to accommodate American race industries including oval track racing, and drag racing, and offroad racing.
By knowing the main characteristics that American racer demands, they designed and engineered the standard measurement springs based on data that they had collected through racers that are at the top of their sport. A slight difference in design than our metric coilover springs.
Many enthusiasts will swap springs from brand to brand with the only noticeable difference being a stiffer or softer ride. But what if a spring could offer a noticeable increase in traction, smoother weight transfer, better ride quality, lower tire temperatures, and a more predictable feel? The engineers at Swift have taken that "what if" and turned it into reality.
All Swift Springs are manufactured using H5S.TW. which is far superior to typical silicone chrome steel and allows them to wind a much more responsive spring with less coils, resulting in reduced un-sprung weight and increased stroke.
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 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.
Unlike others, Swift designed barrel springs with ease and consistency of vehicle setup in mind, their barrel springs design have a maximum of 4" outer diameter (except B5 and B3 series)(Usually located on the center coil of the spring). Because most other manufacture do not design their barrel springs with this rule, most of their barrel springs outside diameter will differ from one rate to another. This creates a hard time for racers especially with tight clearances to test and see which rates will fit and which rate does not. A heavier rate spring can interfere with the suspension A-arm or other suspension components.