W/P & Thermostat Housing Bolt Kit - 12pt. LS1/LS2

The ARP Water Pump & Thermostat Housing Bolt Kit for LS1/LS2 engines is designed for builders and enthusiasts who require dependable performance in high-performance cooling systems. This kit addresses the common failure of OEM fasteners under conditions of boost, heat cycling, and vibration, particularly in forced-induction applications.

Manufactured from ARP's proprietary alloy, the 12-point fasteners in this kit provide superior clamping load consistency and a reduced risk of stripping compared to conventional 6-point hardware. The design of the 12-point heads allows for more even stress distribution, which is critical when working in tight engine bay quarters where socket angles can be compromised.

This bolt kit is ideal for LS1 and LS2 engine swaps, crate motor builds, and high-horsepower street cars, ensuring that your water pump and thermostat housing remain secure through thousands of miles of track and daily driving. Whether you're operating a mild 400hp street engine or a 1000+ hp forced-induction setup, upgrading to these high-quality fasteners is essential for maintaining reliability in your cooling system.