8mm LS Steel & Viton Dual/Single Spring Valve Stem Seals (Suits: 0.4825" Guides) which is much stronger than

which is much stronger than stock steel and mates better with an aluminum case

designed for twin barrel carbys

Other features include availability in several colors

but they also lengthen valvetrain component life and reduce wear and tear on valve stem tips

Speedmaster crankshafts are nitride-hardened

8mm LS Steel & Viton Dual/Single Spring Valve Stem Seals (Suits: 0.4825" Guides) which is much stronger thanValve stem seals control the lubrication of the valve stem as it slides in the valve guide. Too little oil causes stem and guide wear. Too much oil increases oil consumption and can cause a buildup of carbon, leading to valve seat damage and early valve grind. Speedmaster valve seals are posi stop seals made from high temperature Viton material for a long lasting seal.