W/P & Thermostat Housing Bolt Kit - 6pt. LS1/LS2

The W/P & Thermostat Housing Bolt Kit - 6pt. LS1/LS2 by ARP is a premium fastener upgrade designed for LS-series engine builds and restorations. Water pump and thermostat housing bolts endure constant thermal cycling and coolant exposure, making OEM hardware vulnerable to corrosion, seizing, and catastrophic failure during disassembly. This kit replaces those critical fasteners with ARP's aerospace-grade chromoly bolts, engineered to withstand extreme temperatures and prevent stripped threads—essential for any serious LS engine platform upgrade or rebuild.

Constructed from chromoly steel and finished in black oxide, each bolt in this kit resists corrosion and maintains structural integrity in high-heat environments where cast iron and aluminum meet. The 6-point hex head design distributes load evenly across the fastener head, reducing stripping risk compared to 12-point alternatives. Washers are included to prevent fastener pull-through into softer aluminum castings, a critical detail overlooked by budget alternatives. ARP's quality control ensures consistent hardness and dimensional accuracy, meaning you achieve proper clamp load without guesswork or over-torquing.

This bolt kit is essential for LS1 and LS2 owners performing engine assembly, rebuilds, or restorations where reliability cannot be compromised. Mechanics and engine builders routinely specify ARP fasteners for critical cooling system applications because the cost of bolt failure—blown head gaskets, coolant loss, or complete engine damage—far exceeds the premium for quality hardware. Installation follows standard torque procedures; consult your engine manual for correct specifications. Compatible with all LS1 and LS2 configurations, this kit delivers the professional-grade reliability demanded by high-performance and race applications.