Description Reviews Supertech Spring / Retainer kits are precision matched sets for a complete valve train overhaul. Developed for the performance enthusiast that wants the best the industry has to offer, Supertech Spring / Retainer kits are second to none in terms of performance, quality and value. Make sure you pair it with all of the other Supertech items like the valve seals and valve guides! Specs: Coil Bind: 22.2mm Inner Spring (OD/ID): 18.8mm / 12.3mm Max Net Lift: 11.4mm Outer Spring (OD/ID): 23.3mm / 16.8mm Pressure (Open): 163lbs@10mm Pressure (Seat): 65lbs@33.6mm Rate: 9.8lbs/mm