1.263" Od. 0.510" Id. 0.041" Thick Hardened Steel Valve Spring Seat LS1 Oxygen sensors are vital components

Oxygen sensors are vital components that help you adjust to your engine's fuel/air ratio via the electronic control unit (ECU)

Speedmaster only offers planetary gear sets provide superior torque output for modern high-output motors

Some applications feature a thicker deck to solve common warping or cracking issues

This gives you the ability to run a much stronger and reliable transmission to your high performance engine

These Speedmaster fuel pumps feature an improved design for street and strip applications

1.263" Od. 0.510" Id. 0.041" Thick Hardened Steel Valve Spring Seat LS1 Oxygen sensors are vital componentsAs with all other parts in the valvetrain, the area where the spring sits takes a beating. The old standard shims simply will not hold up to the extreme pressures and high rpm found in today's performance engines. Speedmaster offers this set of valve spring shims to solve this problem and eliminate failures.