Ferrea Single Valve Spring 60lbs - Honda D16Z6/D16Y5/D16Y7/D16Y8 - Set of 16 - S10029These single Beehive form valve springs are designed and optimized to reduce valvetrain harmonics, provide greater spring stability, and reduce spring and retainer masses for increase performance and durability in todays harsh racing engines. Type Material Application: Single Spring Special Alloy Outside Diameter: 22. 9 mm Inside Diameter: 15. 35 mm Seat Pressure: 60 lbs @ 50 mm Open Pressure: 155 lbs @ 40 mm Rate Inch: 241 lbs Coil Bind: 32 mm Max