Water pump questions ??

Going to replace the water pump on my 273. When I was racing long long ago in a galaxy before I had real bills. Mopar performance said to use an AC water pump (used less power I guess) So I did.
Does it make since to use an AC water pump..seems to to me. After all an AC car might be harder to cool ??
And has any on used those FLOW KOOLER pumps ? and for that matter flow kooler sells their super duper add on disc ( mounts to current pump).
Water pumps is there a better mouse trap ?????????

From what i understand a waterpump with ac has larger fins. when i called around everyone sold the same water pump ac or not.

not that i have ever herd or experienced!!- What everyone needs for nice proper cooling =is just a shroud!!!!!!!!!!!!!!!!!! find one =make one=have one made!! just do it = quit all the addl watter wetter & additives stuff- unless ur wealthy & just want to change things always?????????????? Remember =all our vans when new -never had any overheat problems.

i installed a FlowKooler water pump recently. i haven't seen any gigantic improvements in performance or temp decrease.

remember =some of the pump[s with smaller vanes will actually =over speeds the water =overheats= as flows quicker or cavatates(air) =the water inside the system. usually a standard waterpump does the job=designed for cooling system sises!!= 

I think I read somewhere one of the big differences between ac and non ac is also the pully ratio. The AC model has larger internals but to keep it from cavitating it is spun at a diff rate than the non AC unit. Just something you may want to think about but then again i may have no idea wtf I am talking about LOL.

Truth be told all these vans ran all over the country during the 60's and 70's with the std setup and no overheating issues so long as your cooling system is in order the isn't really a reason to change the pump out to a AC unit IMO.

Billys -absolutely correct too with all -there were diff sized pulleys for the waterpumps.=had forgotten that !!