[jasonnichols]

there is a variety of pulleys out there most are of decent design and quality. some have smaller (overall diametre) some same as OEM. I went for the same as OEM and upgraded the water pump at the same time . The Eldelbrock water pump empeller has been designed to stop that cavitation.( plus looks cooler ) and yes its the ratios that determine what speed it all runs at. Interesting point is the pulleys on the water pump and crank are aluminium while the alternator is anodized steel with rubber insert. The guy who designed these says that the alternator is the one that wears out