WP SR1355 Spring kit
Wilkes Performance solid roller spring kits. Using made in house Wilkes Performance titanium retainers.
Kit includes, Wilkes Performance titanium retainers, PAC 1355 springs, ID locators, 10 degree machined locks, valve seals
PAC Racing’s 1300 Series Drag Race Dual Valve Spring is the manifestation of the latest technology in the drag racing valvetrain aftermarket. Traditional springs were made with higher loads and rates without concern of spring mass and frequency. PAC Racing has taken years of research and coupled that with exotic new heat treatment methods to produce the next generation of drag racing valve springs. The 1300 Series springs feature a 15-30% reduction in physical mass. This, coupled with a natural frequency increase of 20%, enables your engine to rev higher, faster, and last longer even with aggressive camshaft profiles. These springs are constructed of our signature PACaloy super clean wire and are heat-treated in-house for precise spring rates and enhanced strength. They undergo a multi-peen process to optimize service life as well. Unique to the 1300 Series, these springs then receive ID/OD chamfer finishing, a run through the polisher, and a Nano-Peen™ proprietary surface treatment to improve operating cycles.
- Built using our signature PACaloy super clean wire to ensure strength and durability
- In-house heat-treating for precise spring rates and increased strength
- Multi-peen process to optimize service life
- ID/OD chamfer finishing
- Polishing to improve operating cycles
- Nano-Peen™ Proprietary Surface Treatment
Technical Specs
Outside Diameter: 1.500
Outer Spring ID: 1.050
Middle Spring ID: N/A
Damper: no
Inner Spring ID: 0.726
Install Height: 2.175
Load at Installed Height: 420
Spring Open Height: 1.175
Spring Open Load: 1200
Recommended Valve Lift: 1.000
Spring Rate (lbs./in): 780
Coil Bind (max): 1.130

