Chevrolet installs a 180 thermostat in some of it's crate engines BUT most have the 195.
I run the 195 in all my stuff.......and they run 195 in town, on the road, sitting in traffic.
A lot of people believe (myself included) that the 195 keeps the coolant in the block LONG ENOUGH for the coolant in the radiator to cool down. So the vehicle does not overheat.
When you have a 160 thermostat...........it opens at 160 or so and stays OPEN all the time........and the coolant is just cycling to and from the radiator.........without cooling it.
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