1.263" Od. 0.510" Id. 0.041" Thick Hardened Steel Valve Spring Seat LS1 look no further than PCE

look no further than PCE

Speedmaster one piece silicone rear main seal

The Billet Aluminum Drum wtih Extra Large sprag utilizes OEM intermediate frictions & steels

like lower cost steel ones

They also help to insulate the carburetor from engine heat and provide clearance for linkages

1.263" Od. 0.510" Id. 0.041" Thick Hardened Steel Valve Spring Seat LS1 look no further than PCEAs 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.