Electric Fans

[40 Chev Coupe]

I'm looking here to find out the difference in a straight or curved bladed electric fans. I've used the curved ones before, But I heard that one is noisier then the other, but dont remember which one. Looking to find out the difference, anyone know?

[wayne petty]

curved blade fans are usually quieter...

the shock waves off the leading edge of the blade do not impact the straight legs of the fan motor support with as much force at one time..

whats also important..

using relays in a load dropping configuration to supply the fan motors with as much current as possible..  lets them run at full design speed and gets the cooling cycle performed quickly so the fans can shut off..

electric radiator cooling fans are NOT designed for CONSTANT operation.. when they are operated under power constantly.. the heat build up in the motor can get the shaft HOT enough to melt the middle out of the fan blade..

so run a fan controller of some kind also.   there are some neat ones over at speedway you might want to look at..

http://www.speedwaymotors.com/search.html?query=fan+controller

there are actually a few models of toyota camry's back around 1994 that used power steering pump powered hydraulic fans.. but these used a computer controlled i think variable valve to control fan speed and on off cycle..  it could have just been an on and off valve..  i have not researched it.. might be nice to not need battery power to run the radiator fans..

lastly... electric fans.. actually really need to use a thermostat and a bypass circuit to control the engine temps.. if you have questions on this.. ask..