1.574 Dual Valve Springs (16) Valve Spring - 1300 Series Circle Track - Dual Spring - 538 lb/in Spring Rate - 1.150 in Coil Bind - 1.574 in OD - Set of 16

1.374 Dual Valve Springs - (16) Valve Spring - 1300 Series Circle Track - Dual Spring - 436 lb/in Spring Rate - 1.190 in Coil Bind - 1.374 in OD - Set of 16

1.564 Dual Valve Springs (16) Valve Spring - 1300 Series Circle Track - Dual Spring - 513 lb/in Spring Rate - 1.150 in Coil Bind - 1.564 in OD - Set of 16

1.625 Dual Valve Springs - (16) Valve Spring - 1200 Series - Drag Race Series - Dual Spring - 629 lb/in Spring Rate - 1.100 in Coil Bind - 1.625 in OD - Drag Race - Set of 16

1.545 Dual Valve Springs - (16) Valve Spring - 1200 Series Circle Track - Dual Spring / Damper - 428 lb/in Spring Rate - 1.180 in Coil Bind - 1.545 in OD - Set of 16

1.539 Dual Valve Springs - (16) Valve Spring - 1200 Series - Dual Spring / Damper - 500 lb/in Spring Rate - 1.130 in Coil Bind - 1.539 in OD - Circle Track Endurance - Set of 16