djsprinklesnjo

ok i spoke to a krc tech and a bunch of their dealer techs. so there are no more aluminum (old design) pumps left. which stinks bc they only have the newer aluminum pump that starts around $600 just for the pump! they dont recommend the cast iron one bc its max rpm speed is 5,000 or so. also one person told me the cast iron casing is not as nice looking as the aluminum one. then another person told me they look the almost the same. (so who knows)

anyway i was informed i could put a 6" pulley on the pump instead of the 4.2 and this will slow down the rpms. or i can leave the 4.2" pully on it and change the crank case pulley. which i wanted to do anyway to put on a chrome underdrive serpentine pully kit. (some people i talked to dont recommend this bc it will change the speed of the water pump and effect cooling) but then why would companies make an underdrive kit. im sure it will be fine.

so im most likely going to buy the much cheaper cast iron pump and an underdrive pulley kit. crank case diameter of 4.75 divided by pump pulley of 4.2 = 1.13 x engine rpms of 4,500 = 5,085 rpms.