water pump question

[Ferd Ring]

can anyone tell me if the 4 hole 421 water pump is the same as a 389?

 

[melsg5]

All 4 hole 63 and earlier V8 pumps are the same

 

[cammerjeff]

Just be sure if you are ordering a new pump it has a cast impeller, no a stamped one. The only different 1963 Water pumps are for the Slant 4 engines used in Tempest & Lemans models (the rt bank of a 389 basicly) those ones turn the other way so the impeller is backwards. Found that out the hard way when I owned a 63 Bonneville years ago. They bolt in fine, just won't pump much coolant!