Which thermostat and why?

[Monster]

Tim,

I have an FE and I run a 170 in mine, the thermostat is there to help get the engine to "running temp" and to help maintain the temp once it gets there this is important for engine performance. When cold the engine circulates water via the bypass with the thermostat closed and when the engine reaches the spec temp the thermostat opens however, it still creates a restriction in the cooling circuit. This is to aid cooling and maintain running temp by slowing the flow through the system which allows the coolant longer time in the rad to exchange heat and cool. Natural air flow will (should) maintain a temp of 180- 200 at speed above 25 on your summer days. Your fan will only work when the car is standing still or at low speeds. It is extremely important to shroud your radiator so that the fan can draw from the entire cooling area (All air passing through the radiator should only exit through the fan opening . Fans that mount just to the fins with no supporting shroud will only cool the area directly under the fan.

For sealant I use Permatex Hylomar HPF (Blue)

Hope this helps,

mike 'monster'