PAC Racing RPM Series Valve Spring Single Spring 290 lb/in Spring Rate 1.150" Coil Bind - 1.245" OD NB110020 This inertia weight has six

This inertia weight has six (2-ring design) or eight (3-ring design) computer machined grooves to retain the proper durometer O-rings (dyno tested for each application)

Simply turn knob on adjuster to evenly pull or push spring without kinking or breaking spring

Ford FE Series

DryTech Closed Box

PAC Racing RPM Series Valve Spring Single Spring 290 lb/in Spring Rate 1.150" Coil Bind - 1.245" OD NB110020 This inertia weight has sixProduct Description: Valve Spring RPM Series Single Spring 290 lb in Spring Rate 1. 150 in Coil Bind 1. 245 in OD Small Block Chevy Set of 16 PAC Racing Springs is part of the Race Winning Brands Family. With more than 100 years of spring manufacturing experience. We understand the demands of racing and provide a commitment to all of our customers to provide the best service possible. We continue to expand products and offer expanded onsite technical