By Cool Craft Components

Why rely on another operating system (that being electrical) if you don’t have to?  Mechanical fans turn when the motor turns. However, we highly recommend a shroud properly fitted to the fan and radiator.  The only time you really depend on a fan is at idle or low speed where there is little or no air flowing through the grille.  Shrouds are necessary to maximize the amount of ambient air being pulled through the grille and radiator.  Proper fan and shroud alignment should be leading edge of fan 1/3 in and trailing edge of fan 2/3 out. The air flow off the back of the fan deflects at about a 45 degree angle when set this way.  When the blade extends further into the shroud the air off the back of the blade flows straight back into the block and decreases the airflow efficiency by about 15%.

If an electrical fan is the only way to go then by all means place it on a shroud that covers the entire core.  We often see an electric fan attached directly to the core and the only thing this does is waste the rest of the core surface when you need it the most.  A 16” electric fan attached to a core only cools a 16” circular section of that core. 

Where space is an issue Cool Craft offers a ½” deep aluminum shroud that enables adequate air flow over the entire core and, when combined with a SPAL Thinline electric fan, results in a total depth of  2 ½” .