What degree Thermostat?

The 160 degree thermostat allows your engine to run cooler, making more power by increasing charge density and reducing the propensity for knock. A cooler thermostat can often allow you to run more ignition timing at the new lower coolant temperatures.

The low temperature thermostat is especially helpful at the drag strip when you are trying to cool your engine down between runs. With a stock thermostat, once your coolant reaches 192 degrees, the thermostat is closed and it takes a lot longer to cool the engine down because no coolant is circulating through your radiator. With a 160 thermostat, this doesn't happen until your coolant reaches 160 degrees.