Adding a pusher fan.

I understand what you are saying and I agree with you but what I am saying is that when the car is moving the pusher fan isn't working. When the car is moving the car is cooling enough that the pusher fan will not be running. It will be off because the temp will be not be high enough to kick the pusher fan on. The only time the pusher fan would come on is if and when you would get stuck in traffic and the temp would rise enough to kick it on and then it would assist the factory fan in cooling it down. While you are running at pretty much any speed the air would cool it down enough and the pusher wouldn't be on. I am not talking about having the pusher fan on a switch that runs all the time. It would be on a relay that when the temp rises above say 195* it would come on . That is the way I have it set up on the rat rod. It works fine.
No actually you're missing my point. What I'm saying is that you can only push or pull as much air with the fan(s) as the stronger of the 2 will move. The weaker of the 2 fans with actually just disturb the air flow created by the other fan and therefore actually reduce the total flow. You're better off just running one fan. So it's like this if on one side of the radiator you have a fan that can move 500 CFM of air and on the other side you have a fan that moves 300 CFM, you're not going to be getting 800 CFM of air flow. You probably won't even get the 500 because the weaker fan can't keep up and just gets in the way.