The restrictive housings were corrected 7 or 8 years ago. There shouldn't be many (if any) of those in new stock.

I remember that highly detailed water pump test done on the FMC motorhome with a 440. There was not much difference in water pump volume. All of them moved enough to cool a motor at any regular engine speed.

We are brothers and sisters doing time on the planet for better or worse. I'll take the better, if you don't mind.
- Stu Harmon