PAC 1200 DUAL SPRINGS FOR AGGRESSIVE CAMSCALL SHANON AT 507 445 3235 WITH ANY QUESTIONS. 1200 Series Our standard high performance processed springs with round or ovate wire. 1200 Series springs have excellent load loss while still maintaining a good fatigue life. These springs are developed for economical racing budgets. Weight Outer Spring I. D. Outer Spring O. D. Inside Spring I. D. Install Load Install Height Open Load Open Height Coil Bind Max Lift Max Frequency Outer Frequency Inner