I want to go from a mech. flex fan to a electic fan. How many CFM do I need to keep it cool. Right now it will run all day at 170. If I get tied up in traffic it may go to 210. Will cool right down to 170/180 as soon as I start moving again. What do you guys think. Also I am thinking a puller would be better then a pusher. Do do all agree. TYhe fan that I am looking at is a pusher or a puller and has 16 inch blades at 3000 cfm. Would this more then do the trick to keep me cool.