Water Pump Vanes (propellers)

Someone mentioned in another post that cavitation (bubbles) would be the problem using the wrong impeller. The water pump pulley on A/C vehicles is smaller, meaning it spins faster, thus the smaller impeller is used so as not to make too many bubbles. The water pump pulley on non A/C vehicles is larger, meaning it spins slower and uses the larger impeller to make up for that slower rotational speed.