Pete wrote: The Factory Service manual says, the electric fan comes on when the coolant reaches a temp of 217* and shuts off when it gets to 209*.

Guys that sorta sez it all! The factory WANTS the temp above 209*.. In fact they don't even start the fan till 217*. That in itself should tell you something about the intended temp of your engine. With a good cap on there your coolant will not start to boil till bout 240*. If you are far enough South to run pure antifreeze IT will not boil till over 400*.
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />