Ferrea Nissan Skyline RB25 NEO Dual Valve Spring - Single
6 Cyl. In-Line - 24 Valve (NEO)
Dual Spring - Turbo/Special Alloy
Outside Diameter: 20.8 mm/28.0 mm
Inside Diameter: 16.51 mm/20.8 mm
Seat Pressure: 95 lbs @ 30 mm
Open Pressure: 195 lbs @ 20 mm
Rate Inch: 254 lbs
Coil Bind: 17.5 mm
Max Net Lift: 12 mm
This Spring requires Ferrea Titanium Retainer # E11048 and BOTH, Ferrea Spring Seat Locator # SL1037 (INT) and #SL1150 (EXH) AND Factory supplied Spring Seat Locator. Maximum Retainer Step 2 mm