Ah, things are never simple.  This is probably another of those items that will show different results based on how the experiment (our radiators) is set up.  I REALLY want a low mounted water pump and will reconsider this approach.  I'll try to get to the junk yard in the next couple of weeks and identify some donor cars (Toyota) for a 2 outlet water pump. 

I'll sure be glad when it warms up some.  My workshop is 40F today (just outside Little Rock, AR).  I know that I get no sympathy from you guys up North, but my hands just HATE cold.  OK, enough bitching for the moment.

Ken Powell

Hi Ken, nope, they never are : )

On the low water pump thing, I used to feel the same way until I had an actual incident where I was loosing coolant from the system.  (a malfunctioning pressure cap).  If the pump had been at the bottom of the system, it would have continued to pump until it had flushed just about every drop from the system.  As it was, the pump stopped working when the level dropped 2 out of the 7 quarts in the system.  (I know this from other past experiences)  The good part is, this leaves 5 quarts in the engine to cool it while boiling away.  This was enough to get me 8 miles to the nearest airport with no engine damage.   Still had about 3 quarts in the system when I shut down.   Coolant temperature was about 250 deg. as the coolant boiled off.  I was at very low throttle setting.

There is a good chance I would have been calling a cab and flying the 900 miles to home on Delta if the waterpump had been able to get at all the water in my system. 

Tracy