Formula Nippon
10 inch length
and spring rates from 3kg (168lbs) all the way up to 34kg (1900lbs)
spring lengths from 127mm (5in) to 280mm (11in)
Since the metric system is used widely in the sport compact and road race market
Swift Springs Metric Coilover Springs 65mm ID, 4 inch length, 24 kg/mm Pair Metric Coilover Springs Formula Nippon65mm ID, 4 inch length, 24 kg mm Swift Metric Coilover Springs are made from a proprietary (H5S. TW.) Material. This allows Swift Springs to manufacture a spring that is has more stroke, increased traction and handling as well as a spring with less coils, resulting in a lighter spring with less unsprung weight. The same springs are used in Super GT, Formula Nippon, F3, F3000, Super Taikyu, IMSA, Pirelli World Challenge, Rally America, VLN, Le Mans