Quote Originally Posted by green34ford View Post
A thermostat will keep the water in the block longer and help cool the engine down. that's what I have always been told, that without one the water is moving to fast to absorb the heat.
I agree, and I also believe this is why a good sleeve type thermostat is better that a disc with a hole in it or even a poppet type thermostat. As the load changes on the engine, the temperature in the coolant will vary, certainly not a one size fits all situation.

Also, with a new motor, one that hasn't fully "broken in", the friction factor is a bit higher. Other things to check would be fuel/air mixture (to lean equals heat) and timing not set properly and verify the centrifugal advance works properly.

Of course the above is my opinion, ymmv... yada yada yada... hope it helps