Weird ? about small block pulleys

Cool chart, is that from an FSM?
That’s interesting, because the standard factory ratio was .95:1 for the water pump pulley. AC cars were overdriven at 1.3:1 or 1.4:1. But they also got a water pump with only 6 vanes, versus the non-AC cars that got an 8 vane water pump and the .95:1 ratio.

The factory pulley ratio’s by engine…

View attachment 1716001616