GM LS1 & LS2 Hi-Flow Thermostat, 160°F (71°C) 160°F Temperature

Engine management depends on reliable, properly calibrated thermostats. The GM LS1 & LS2 Hi-Flow Thermostat opens at 160°F (71°C), designed to reduce flow resistance and promote efficient coolant movement for LS1 and LS2 engines. Crafted from copper and steel, this high-flow design supports quicker, more consistent heat cycling while helping maintain optimal operating temperatures. It’s a direct drop-in replacement with no modifications required and includes the rubber seal already installed for a ready-to-fit install.

Key benefits

• Opening temperature: 160°F (71°C) for a cooler-running engine profile versus factory units
• Hi-flow design reduces coolant restriction, aiding faster warm-up and improved thermal response
• Copper/steel construction for durability and reliable heat transfer
• Direct drop-in installation with no modifications needed
• Includes rubber seal; compatible replacement rubber gasket available: AF59-1143 (53.9mm O.D.)
• Part of Aeroflow Performance GM LS thermostat lineup, which offers two temperatures lower than factory units

What’s included and compatibility

• Includes rubber seal for immediate installation
• Replacement Rubber Gasket to Suit GM LS1 and LS2 (53.9mm O.D.) AF59-1143
• Compatible with GM LS1 and LS2 engines

Installation considerations

This is a straightforward, direct-fit replacement that requires no modifications. Proper sealing ensures a reliable seal against coolant loss and consistent thermostat operation. Thermostats can fail by sticking open or shut, which affects heater performance or can lead to overheating; choosing a properly rated, high-quality thermostat helps maintain stable engine temperatures and protect against thermal-related issues.