RX7Club.com - Mazda RX7 Forum - Gain power by converting to an e-fan?

Quote:

Originally Posted by RotaMan99 (Post 7028094)

So getting back to the e-fan Topic.

I was just thinking. Which is not always a good thing. As seen above :)

Putting a E-fan on a shroud would cause the fan to run at a higher efficiency then putting it straight on the rad due to the increase surface area it is able to pull air through, correct? Not saying the conversion from electrical to mechanical but the amount of current it would consume plus the amount of CFM it would pull, since having it directly on the rad decreases the surface area, or the amount of gaps it can pull air through, which would limit the CFM, since the CFM rating is measured also by the amount of total surface area the fan can pull from, otherwise it would be at zero static pressure, open air.

Am I going off the deep end here and thinking stupid?

I had a little trouble following you here, but I think yu are on the right track.

Are you talking about the factory fan shroud? If it doesn't fit the fan blade properly you will lose much of the benefit of a proper fan shroud.

I think that what you are saying is that using a properly designed shroud that completely covers the radiator surface will improve the effectiveness of an efan. It will evenly distribute the negative pressure across the entire face of the radiator, thereby equalizing the face velocity on the radiator at all points. This will also lower the static pressure that the fan is working agains, which is alway a good thing on propeller fans. The total cfm will likely rise as the fan is now working against a smaller load.

In other words, it moves more total air across more of the radiator surface.

The amp draw will likely decrease, but not by a significant amount in this application, since these fans tend to have poorly designed blade configurations and enough power to run at a stall without overloading the motor.

Properly designed fan shrouds increase fan efficiency in several other ways as well; Nz can do a better job than I can of detailing the benefits.

i personally believe that the reason the Ford Taurus fan is so highly regarded is that the design of the fan blade, the shroud and motor is a complete package that has optimizes the effectiveness, efficiency and minimizes the noise.