There are two kinds of clutch fans, straight viscous coupling and Thermostatic.
The viscous slips all the time never quite locking up, but the hotter the air coming thru the rad, the closer it gets.
The T-type is more sensitive to the air-temp coming thru the rad. It cuts in and out around a non-adjustable preset temperature point. This is nice for a streeter, that spends a lotta time at slower speeds.
Once the car gets over 30 mph, you can probably depend on ram-air thru the rad to cool your engine, so I would chose the straight viscous type.
I've never seen an 8-blader, that's a lotta blades. You could experiment with fewer blades, but I had no success with a flex-fan.
