Electric fans might be a good "belt and suspenders" approach to assist a mechanical fan, but there's no substitute for a fan with 100 horsepower or so driving it. My father's B-17 didn't have four 1200 HP electric motors driving the propellers. They used big gasoline engines and 3 blade propellers 12 feet in diameter for a good reason. By the time you consume enough electric power to do much good keeping an engine cool, fan noise is going to be a problem- - - -no way to avoid it. I'd suggest trashing the "puller" fan and going back to an engine driven one, and maybe adding an auxiliary pusher for traffic and/or air conditioner assistance only when necessary. If coolant isn't boiling out past a pressure cap, the engine isn't "overheating" no matter what the temp gauge indicates.
Jerry
