Re: [Chrysler300] 1962 383 Water Pump Housing Question

When Chrysler published it's racing manual in the late seventies, it made mention that there were two basic big block water pumps. The non ac engines had a six blade impeller that used a large diameter drive pulley. The ac engines had an eight blade impeller that was a much smaller diameter than the non ac. The ac engines also used a much smaller drive pulley. The theory was that the smaller ac impeller with eight blades would spin faster at low speeds to aid cooling with the ac operating. The manual cautioned against using the wrong application pulleys as the smaller one would cause a non ac water pump to cavitate a high rpms and an ac engine would overheat with the larger pulley. I don't remember it going into much detail about the different housings. Having seen both styles of pumps with either stamped steel, cast iron, or plastic impellers over the years, it would stand to reason that the housings would be somewhat different for each style of pump. The only way to be sure(?) would be to have access to the factory parts manuals for each year and compare them for each application.