
Katech LS1-Style Billet Thermostat Restrictor
Billet Aluminum Water Restrictor for Compatible Gen III and Gen IV Race Engine Applications.
The Katech LS1-Style Billet Thermostat Restrictor replaces the thermostat with a water restrictor in compatible GM Gen III and Gen IV engine applications using an LS1-style thermostat configuration.
Race Use Only: Designed for off-road race cars. This component eliminates the thermostat's temperature-regulating function.
Features & Benefits
- Replaces the Thermostat with a Water Restrictor
- Billet Aluminum Construction
- Designed for Compatible LS1-Style Thermostat Configurations
- Intended for Off-Road Racing Applications Only
- Proudly Engineered and Manufactured by Katech Engineering in Clinton Township, Michigan, USA

Technical Specifications
- Product Type: Thermostat Replacement Water Restrictor
- Material: Billet Aluminum
- Engine Generation: Compatible GM Gen III and Gen IV Applications
- Thermostat Configuration: LS1-Style; Verify Existing Assembly
What's Included
- One Billet Thermostat Restrictor
Thermostat housing & thermostat seal is not included.
Fitment & Installation Notes
Confirm the water pump and thermostat housing configuration before ordering. Gen III or Gen IV engine designation alone does not establish fitment with every cooling system arrangement.
- Not Intended for Street-Driven Vehicles
- Designed to use OEM GM thermostat seal
- Verify Fit with the Existing Thermostat Assembly
- Inspect Housing and Sealing Components During Installation
- Check for Coolant Leaks After Assembly
- Monitor Coolant Temperature During Race Operation
Why Choose Katech
The Katech LS1-Style Billet Thermostat Restrictor provides a thermostat replacement option for compatible race cooling systems. Select the restrictor to match the installed cooling components and the engine's operating requirements.
For thermostat configuration and race cooling system questions, contact .
