It is possible to add two or three 4" Computer Fans to your cooler. When used in a "Pusher" configuration they can work very well. Pusher meaning mounted to the front of the cooler; away from the radiator side. Radio Shack does sell a suitable fan for cooling computer cabinets. These are not the little clip on fans used for u-Processors that have little heat sinks attached. They are what we used to call "Muffin Fans" that are around 5-6" box square.
There are two such fans mounted on my transmission cooler that I added by default. Here is the rub; mine are connected to a controller unit IFB.
I designed and built it out of spare electronic parts and therefore its not available in a store.
If you do decide to add such fans you can safely attach both fans to the cooler, and than supply power and ground to them from an accessory or accessories circuit ran from off the engine. Since both fans are 12V, and have negligible current (>1Amp. ea.) it shouldn't be too hard. However be careful with your polarity when making such connections (+12V) is the red lead for such fans available from Radio Shack or similar. Make sure that your wiring is "Mil-Spec", and weather tight and use wire capable of being exposed to weather. I don't have pictures since I didn't think it would have been of interest.
