I too had an electric pusher a long time ago. It does prevent full air flow from entering the radiator fins, but the electric fan freewheels, so it doesn't actually block air. But it does have a slight effect on airflow white at cruising speeds. Just acts like diffuser, preventing air from going directly from the grille openings into the radiator.
The electric pusher works really well at low speeds, especially sitting in traffic, as it moves enough air, while idling, to simulate the car going 20-30 mph (approx).
Also, the electric pusher does wonders on those hot days when you have to shut the car down for 5 minutes or so, such as when getting gas. Typically, without any electric pusher, when you go to start the car back up after a 5 minute hot soak, the tempo gauge is usually 5-10 degrees hotter. Allowing an electric pusher to run while the engine is off usually eliminates that problem.
You can also try pulling the thermostat. Many people believe that makes the car run hotter, but people that have tried it know that it does make a difference, and the engine runs cooler. I've run one of those restrictor plates (Moroso) before, which is just a thin disc that's replaces the thermostat, and it has a hole in the middle. Works the same as if you hollowed out your thermostat. Your car will take longer to warm up, but eliminating the thermostat does seem to work on our old Pontiacs, most likely because our cooling systems aren't very strong and the coolant does not cycle very fast.
Water Wetter, used with straight water, also works. I've tested that stuff many times, and it does indeed drop the temps by 5-10 degrees.
