Car getting real hot....

CFD244 said
My '71 service manual must have a mis-print? Where it references the the ratio, it specifically states "fan to crank" ratio. That being said, standard cooling is listed at .95:1 ratio (fan smaller than crank equals over-driven), while A/C cooling is listed at 1.31:1 (fan larger than crank equals under-driven). This logic makes no sense, while yours does.

I see where you are coming from and why that could be misleading.
The charts in the earlier manuals like posted here just say ratio under Fan.

@Dana67Dart has previously posted the measurements from his car.
"My 67 273 (no AC) has about 6.125 crank and 6.5 water pump pulley, that is a 0.95:1 ratio (6.125 / 0.95 = 6.47)"

I would do the math this way if calling it Crank to Fan ratio.
6.125" Crank : 6.5" dia Fan and pump
We want the second part to equal 1 so we divide both sides by the diameter 6.5"
0.94 Crank : 1 Fan

Tha makes sense since we know the fan is just slightly underdriving the standard water pump and fan.

In this post, is a photo of a "1970 up" single sheave crank pulley with an outer diameter of 6.5"
And in the next post presumably the matching water pump pulley which looks to be 6.8" O.D.
6.5" dia Crank: 6.8" dia Fan
.95 Crank :1 Fan

So I think that's all right. Its just how you look at the numbers.
A/C pulleys are sometimes more complicated as I've seen some that have different diameter sheaves on one pulley.
But here's a picture of 1970 engine and we can clearly see the fan and pump are driven faster than the crank turns

Photo from this post Need measurments on 1970 340 AC water pump pulley please

This has a bunch of good comparisons and measurements if any one needs
Pulley ID thread