We have discussed electric water pumps many time and I am always a little reluctant to suggest using one for an actual race engine water pump as they are typically not capable of making any kind of pressure and still have sufficient flow to cool a race engine. I happen across this Bosch electric water pump in "Race Engine Technology" and this looks like the real thing! 160 liter/min (73 gallons/min) at a pressure of 1.5 bar (approx 22 psi). Now that is mechanical pump performance at a big savings in power to drive the pump.
Go to:http://www.bosch-motorsport.de/content/downloads/Products/resources/33818018571/en/pdf/Electric_Coolant_Pump_ECP_160_Datasheet_51_en_33518712459.pdf
Check out all of the specs and performance. Not sure of the price but if it is German it is expensive although most race engines are pretty costly too!
Rex
Now that is one hell of a pump.... 6o amps!!!! I bet its pricey