I"ve run many elect. fans and they've worked well. I just put a pusher fan on a roadster I'm building. I had to nip the corner off one fan blade as it was just touching a part of the bracket I made to hold the fan. I had to cut one small section of the guard around the fan to get to the blade. This go me to thinking if I removed the entire guard a lot more air would pushed by the fan as the guard blocks some the air to the fan. I would think 30% of the air is being blocked by the guard or is it possible the guard is designed so that in fact isn't blocking any air and pulls the air around the bars in the guard.......anyone have any thoughts???????