Thread: factory fan cfm
View Single Post
Old 10-21-2019, 12:17 PM   #3
Senior Member
rotorwrench's Avatar
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 10,430
Default Re: factory fan cfm

The crank fans for 39 through 41 models that had them were actually relatively well centered. The crank hole was damn near right in the middle of the radiator and the radiator was dropped down especially for them. The ones with the generator fan were less so. Trucks also used 6-blade fans on some applications but most of the older belt drive cars were 4-blade till the 3-blade 8BA type came along.

The cubic feet of movement does depend a lot on rpm. More blades will move more air but take more power to turn and also make more noise. An engineer could come up with some flow dynamic calculations but I don't know if it even matters as long as it pulls some air at idle. Once a car is moving at a good speed, there is plenty of flow going on there.
rotorwrench is offline   Reply With Quote