[HO455]

Originally Posted by CSchmidt

cause it got to temp kinda quick thats why i switched it out.

A thermostat will never cause an engine to heat up faster. The thermostat only reacts to coolant temperature. It won't add heat to the coolant

The thermostat should be closed when the coolant is below the rated temperature of the thermostat. The job of a thermostat isn't to keep the engine from overheating, that's the radiators job, the thermostat is there to regulate the coolant flow, so the engine stays in its most efficient temperature range. The thermostat does its best work when it is cold outside.

However because thermostat is not an off on switch it may take 5 or 10 degrees of temperature change to get the thermostat to completely open (or close). So it may be rated for 180 degrees but it could start opening at 175 or 184.

If the thermostat is stuck open it could cause the engine to take longer to reach operating temperature.

As previously stated you may need a high flow thermostat. As inadequate flow may cause the engine to run warm. This would be noticed when driving on the highway in hot weather or when the engine is heavily loaded for extended periods

The rule of thumb for temperature creeping up at idle is caused by not enough cool air flowing through the radiator. Whether that is from blocked fins in the radiator or insufficient draw by the fan or hot air being recycled from under the engine to the front of the radiator. (3rd gen F-bodies suffered from this if the small air dam under the radiator got torn off or removed).

In hot weather being too close to the car in front of you at the traffic light of can cause the engine temperature to rise, if the vehicle in front of you has their exhaust feeding directly into your radiator.