Isky Cams Endurance Plus„¢ Dual Valve Springs W, Damper (16) - 1.530" O.D. - 420 lbs., "Rate - 1.160" Coil Bind Sprint Car Driveline & Rear End Holley 4500 Series

Holley 4500 Series

1966-1967 Chevrolet Malibu

2011-2014 Jeep Grand Cherokee Overland

tip diameter x 2

Fits SU128-LM-AC

Isky Cams Endurance Plus„¢ Dual Valve Springs W, Damper (16) - 1.530" O.D. - 420 lbs., "Rate - 1.160" Coil Bind Sprint Car Driveline & Rear End Holley 4500 SeriesThe Endurance Plus series of valve springs utilizes a specially processed Tool Room Material outer spring for increased endurance reliability beyond the "SP" series. Endurance Plus springs are designed for late models, modifieds, etc. , and are Spintron Test Proven up to 8400 rpm for 850 racing miles. As the world's largest racing, performance, and economy cam manufacturer, Isky maintains a dynamometer testing program for constant improvement of