Providing the best sealing properties and spring clearance, viton valve seals are an excellent choice in performance applications. The 520 seals have a .575" OD and fit applications with 5/16" valves and .530" OD guides.
Available individually under 520-1, in a set of 12 under 520-12, in a set of 16 under 520-16
Engines w/ 0.530" OD Valve Guides and 5/16" Valve Stems
