DJ Rock HGS400 Engine Cylinder Head Gasket Set

Engine sealing set overview

The DJ Rock HGS400 is a premium engine cylinder head gasket set for complete top-end service. It is built to maintain combustion pressure and help seal oil, coolant, and gas passages during cylinder head repair.

Compatible With 1986-1989 Mazda 323 and 1987-1989 Mercury Tracer, this set supports a full reseal during head removal or replacement. The HGS400 part number is also useful when cross-checking applications for the same engine service.

Key features

• Premium-grade sealing set for cylinder head service
• Non-asbestos construction for modern engine repair needs
• Includes sealing components for intake, exhaust, valve cover, and related engine passages
• Multi-layer steel, graphite, composite, rubber, silicone, EPDM, and Viton materials used where applicable
• Designed to meet or exceed OEM quality standards
• 78 mm cylinder bore diameter attribute

Detailed application notes

The HGS400 is intended for top-end engine work where the cylinder head, block, and related sealing surfaces are being serviced together. Its component coverage helps restore sealing integrity across multiple engine interfaces, reducing the chance of leaks after reassembly. The HGS400 part number appears in applications for Mazda 323 and Mercury Tracer models listed above.

This part cross-references Walker Exhaust (e.g., 21677) for the same application.

What it helps address

• Combustion pressure loss at the cylinder head sealing surface
• Oil leakage from valve cover and related upper-engine seals
• Coolant seepage at gasketed engine interfaces
• Gas leakage from intake or exhaust sealing points
• Seal wear during cylinder head replacement or overhaul

Installation notes

Clean and inspect all mating surfaces before assembly. Verify bore size, gasket layout, and engine-specific sealing requirements before installation. Follow factory torque procedures and replace torque-to-yield head bolts when the service procedure calls for new fasteners.

Quality assurance

DJ Rock positions this set as a premium sealing solution built to OEM-quality standards. Non-asbestos materials and application-specific sealing components support consistent engine service results.