You know what? **** it. Let me break it down for you on how you can render an electric fan completely ineffective (please note that I may seem like I am repeating my previous points) by being a total redneck:
1. Just hanging an electric fan behind a radiator is hack, it actually needs to be sealed to the core. And quite closely I might add;
2. This is assuming your fan actually had a shroud and could be sealed to the core (and is large enough to seal the entire core and not just part of it);
3. Ensure that the electric fan can actually provide the necessary flow (rated in CFM) to pull the air needed to cool the engine (most of what Summit and Jegs sell is crap, get an OEM-based setup);
4. The fan shroud will also need to be able to bleed of air flow coming through the radiator at speed, it prevent the air from deadheading inside the usually tight shroud. This usually some ports or flaps that open;
5. The electrical system need to be up to task, if there is a voltage drop or improper wiring (like feed it off the battery and not the alternator with a relay) it just adds issues; and
6. Make sure the fan turns off at highway speeds (ie temp turn on point is above cruising temps), it doesn't do anything of value if the system is sealed well. But, sh*t I already said that.