440 needs to be Cool

Yellow1 - Welcome to the world of BB Dart Baby! - Yes, I am having the same problem. I started with a aluminum 2 core Griffin radiator 26 inch (sounds like the one you have), the propeller as described in gregs post and a pusher fan. Car was a bit lean and on after driving for a bit could not control the heat.

Now I fattend the crap out of it, put on a CC375 Champion, Jegs electric pump and twin fans - waiting for shroud. Works good, but once it gets in traffic does the same, waiting for shroud - I hope it works better.

OK - so, my recommendation find a fixed fan, my experience with the flexs is they dont pull as much low RPM, truly the propeller will be a good addition. The a pusher 16 inch on the other side - and are you too lean? Just a thought - sorry for the rambling, but I am pulling my hair out with this issue too. The 16 I used was about 2000 cfm - and I think GTXman has other good insight, but it sounds like you have a shroud, I would keep that.