1 16" mechanical fan with a shroud will cool that no problem. I also use Evans in my filled block 511 and it cools great with mechanical fan and water pump. I have since switched to all electric with dual 12" spal paddle fans. Will see how this works, but I think its gonna be fine. Last year I tried dual 12" spal curved blade fans and it would not cool properly, ran 218* in the heat driving. Spal has 10" paddle fans, but they only move 1100cfm each. Not enough in my opinion. I have a 26" radiator in my A body and dual 12" fans fit nice. Look at A1 Electric, they have all the Spal fans layed out with specs. Andy runs a Mechanical fan, they will cool just fine with a shroud. Oh and my 12" paddle fans move over 3200cfm together, I think that's what it will take in the heat.