electric water pump
benefits are constant coolant flow at all rpms. i read someplace the flow is more than the stock pump generates at 6000rpms...and has that flow at all rpms. also you have reduced rotating mass on the front of the motor, which means less parasitic loss of power (kindda like underdrive pullies). should translate to 10-15rwhp more.
downside is cost, and the possibility of failure at inopportune times, and without warning. after all it is an electric motor.


and it is a nice piece of bling underneath the hood...if it wasn't for that $500+ price....that's a lot of money