SCE MLS Spartan Cylinder Head Gasket 4.123 in Bore 0.051 in Compression Thickness Passenger Side Multi Layer Steel GM LS Series 29107BL compatible with hydraulic roller camshaftsMust Size:6 5 8 (53) compatible with hydraulic roller camshaftsMust be used with an MSD Ignition ControlSupplied with small diameter cap with HEI style terminals and race rotor (will accept 8441 Cap A Dapt)Nylon pads ensure smooth operation of the advance weightsAdvance weight pins are staked and tig welded to the plateMechanical advance assembly can be locked out for crank trigger systemsAdvance plate and weights are fine blanked from chrome moly steel and QPQ coated for friction reductionPolished steel shaft is QPQ coated and guided by a sealed ball bearingMaintenance free magnetic pickup and precision reluctor create stable trigger signals throughout the rpm rangeCNC machined billet aluminum housing and billet aluminum baseVacuum advance canister for improved economy (can be locked out)Easy to adjust mechanical advance with supplied springs and stop bushings┬ ¼Î“ÇáBillet housing is 5 8” smaller in diameter than stock Ford distributorsCARB E Vapor Guard They offer a variety of different materials for a large selection of applications Cylinder Head Gasket