PAC Racing RPM Series Valve Spring Dual Spring 500 lb/in Spring Rate 1.000" Coil Bind - 1.324" OD RG200012XL These Performer RPM cylinder heads

These Performer RPM cylinder heads are designed for 400

Noticeable idle in 318

1975-1977 Plymouth Gran Fury

the FAST Magnet Crank Trigger maintains compatibility with other brands' ignition systems

PAC Racing RPM Series Valve Spring Dual Spring 500 lb/in Spring Rate 1.000" Coil Bind - 1.324" OD RG200012XL These Performer RPM cylinder headsProduct Description: Valve Spring RPM Series Dual Spring 500 lb in Spring Rate 1. 000 in Coil Bind 1. 324 in OD GM LS Series 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