MANLEY NexTek SERIES High Performance Valve Springs [Maximum Valve Lift .600 | O.D. 1.076 Top 1.311 Bottom | I.D. .650 Top .885 Bottom | Installed/Open Pressure 150 @ 1.800 355 @ 1.200 | Rate (lbs./in.) 341 | Coil Bind 1.085 | Weight (grams) 79] (GM LS) : COLORADOSPEED - LATE MODEL DOMESTIC (AMERICAN MUSCLE) | IMPORT (EUROPEAN | SPORT COMPACT) AUTOMOTIVE PERFORMANCE PARTS