Quote:


Your thermostat only regulates the minimum temperature, not the maximum.

If an engine runs down the highway at 200 degrees with a 195 thermostat, then it will run down the highway at 200 degrees with a 160 thermostat. At best a lower rated thermostat will just delay the amount of time it takes to get to the system operating temperature.



No, if you're running a 160 stat and doing 200 degrees on the highway, all that means is your cooling system does not have the capacity to bring your temps down to t-stat level. If everything is working properly your cooling system should always be at the t-stat rating.

If you read 200 on the gauge with a 195 t-stat, that doesn't mean the cooling system is over its max cooling capacity, all that means is your gauge is not accurate to .0000000%. Look at where the sender is placed, gauge accuracy variation and how the cooling system is setup. If you're getting 200 on the gauge with a 195 stat, in all likelyhood nothing is wrong. Now 200 on gauge with a 180 stat, now there I would say your cooling system could be doing better. Not going to hurt anything running 200-220, but IMO a perfect cooling system should be able to keep the temp at t-stat level.