How much power with a manual water pump?

Interesting , two 426 hemi`s, 2 hot chevys, and a 505'' 440 , never had a pump come apart .

Yep, pulled the shaft right out of the bearings and impeller and destroyed the radiator, shroud and fan TWO Saturdays in a row.
Lucky I had a buddy that worked in a wrecking/scrap yard and during those same years there were a lot of Mopar big block cop cars in the yards.:D