Supertech Dual Valve Springs for Mazda MZR / Duratec 2.0L 2.3L 2.5L Engines

Dual Valve Springs for Mazda MZR / Duratec 2.0L 2.3L 2.5L EnginesSet of 16 Dual Valve SpringsSPR-TS/DUR-D1Outer Spring: OD 27.50mm - ID 20mmInner Spring: OD 20mm - ID 15.20mmType: Dual SpringPress.Seat: 83lbs @ 35.0mmMax Lift: 14.30mmCoil Bind: 20.70mmRate: 12.10mmSPR-TS/DUR-D2Outer Spring: OD 27.50mm - ID 20mmInner Spring: OD 20mm - ID 15.20mmType: Dual SpringPress.Seat: 70lbs @ 36.2mmMax Lift: 15.50mmCoil Bind: 20.70mmRate: 12.10mmNote: These Dual Valve Springs require the use of Supertech Retainer Part # RET-TS5.5/T1 & SEAT-DUR1 or SEAT-DUR2 - (Sold Separately)Our valve springs are computer designed to ensure that wire stress levels do not overpass the limits of stress defined in the diagrams of fatigue. We also utilize computer software that allows us to ensure that the harmonics are under control. All Supertech valve springs are made with premium super clean Chrome Silicon Vanadium Steel alloy for higher performance & durability at high rpms. Using high quality steel alloy