Bosch water pump
These are OEM, Bosch, ContiTech:
That impellar freaked me out. Sure it'll work, but its nowhere NEAR as efficiant at moving coolant as the shovel type found in the OEM and Bosch pumps. Now lets look at the outlet. That was the final final.
Bosch on the left, ContiTech on the right
Look at the outlet!!! not only is the ContiTech jippin you on the impeller, but the outlet size. It seems to me that you'd want the biggest outlet you could. It seems choked.