[DeTomaso] Stock fan output vs. Flex-a-lite

[SOBill at aol.com]

At 
_http://www.performancecenter.com/autoparts/flex-a-lite/electric_fans/flx240.html_ 
(http://www.performancecenter.com/autoparts/flex-a-lite/electric_fans/flx240.html)  you  will find a picture of a Flex-a-Lite fan and shroud. Note 
that these are listed  as "pusher fans" by Flex-A-Lite.
 
If you click the picture of the fan and shroud, you can see  that the fans 
cover the greatest percentage of the radiator  area. The area the fans do not 
cover will block air flow due to  vehicle motion no matter how the shroud is 
mounted.
 
The fans will create a pressure in the shroud if mounted on the  front of the 
radiator and a suction in the shroud if mounted on the back of the  radiator.
 
2,500 cubic feet of air per minute moved thru the two 12 inch  fan openings 
and assuming no obstruction from the radiator core or the  fans equals an air 
flow rate of 18 mph. The actual flow rate thru a  radiator will be less. Fans 
are only helpful at very low speeds and above about  10 mph are actually an 
obstruction no matter how they are  mounted.
 
Shrouds mounted on the back of the radiator which incorporate  "flapper 
doors" which close when the fans are able to create a suction but open  when 
sufficient vehicle motion created airflow is present offer the  best of both worlds.
 
Go easy on Sean. He ain't stupid.
 
SOBill  Taylor
sobill at aol.com