The Stovebolt Site Forums The Shop Area General Truck Talk Thermostat,no thermostat, that is the question

Slow,

The 200 won't keep it COOLER, but it will keep it more efficient. Try it, and see if you find the truck running too hot. If you do, swap down to the 180.

There are so many factors -- the health of the cooling system, the size of the engine, the richness/leanness of the carb, the temperature, the engine RPMs, etc, that it's hard to sit here and work out a perfect answer. Try it and see

Brian