* Engine modifications: Has the engine been modified (e.g., higher compression, performance camshaft)? Modifications will change the optimal operating temperature.
* Climate: A colder climate might benefit from a slightly lower temperature thermostat to ensure quicker warm-up, while a hotter climate might use a higher temperature one for better fuel economy.
* Original specification: The original thermostat temperature rating varied depending on the truck's specific options and the factory's specifications for that model year. Consulting a parts catalog for your specific truck (using the VIN is best) will provide the most accurate information.
Generally: A 160°F-180°F thermostat is a common range for a stock 350 Chevy in a 1977 truck. However, 195°F is often considered the optimal operating temperature for a small block Chevy 350.
To find the right thermostat:
1. Check your owner's manual: This is the best place to start. It should specify the factory-recommended thermostat temperature.
2. Look for markings on your existing thermostat: The temperature rating should be stamped on the thermostat itself.
3. Check a parts catalog: Use your truck's VIN to ensure you get the correct parts. Online parts stores (like AutoZone, Advance Auto Parts, Napa Auto Parts) and online catalogs can provide this information.
4. Consult a mechanic: A qualified mechanic can help you determine the appropriate thermostat for your specific vehicle and its condition.
Don't just guess! Using the wrong thermostat can lead to overheating or poor engine performance and fuel efficiency. Take the time to find the correct one.
