[JLMounce]

It is absolutely true that copper is a better heat conductor than aluminum. That's not the whole story though.

On a brass/copper radiator, the copper fins have to be attached to the brass tubes. That's done with either solder or brazing depending on the construction methods. This creates a thermal choke point that diminishes the heat transfer from the fins to the tubes and thus into the coolant. Because the solder or brazing process introduces extra material between the fins, this also means the fin counts are necessarily less. As the radiator sees pressure build, the tube sizes are also limited because due to ballooning of the soft tubes. This means you need to stack additional cores to reach enough surface area. What gains you get from using the superior thermal conductivity of copper is reduced by how the unit is manufactured.

Aluminum radiators are constructed using controlled atmosphere brazing, which eliminates that thermal choke point. Aluminum being stronger also allows for larger tubes and tighter fin counts without external brazing alloy or soft solder that reduces fin count.

Point being, you can find brass and copper radiators the same as you can find aluminum radiators, but in comparable price points, I wouldn't expect the copper/brass unit to cool as well because it's likely constructed with soft solder. Even the more expensive units (some as much as $1500 for just the radiator) are still using silver alloy brazing material, that again creates a thermal choke below the heat transfer rate of an aluminum unit. There's a reason OEM's don't use copper/brass radiators any longer. For the needed cooling capacity, they are more expensive, heavier and take up more space.

As far as the fans are concerned, your radiator doesn't know how is in front or behind it. If you need 3000cfm to cool your engine, doing so with an electric fan or mechanical fan doesn't matter, just as long as you get there.

I can tell you, this is the best my car has ever cooled itself. It's still not perfect and I've always had a slight to moderate idle heating problem. I've had everything now from a factory shroud with copper 3 core radiator and the factory 19" flex fan, an aluminum radiator with a single 15" electric fan and now another aluminum with dual 14" electric fans.

I had the car out in 101 degree heat this weekend and the setup ran at or below 190 while moving, but did see increased time to creep at idle. Still not enough to really be worried about unless I got caught in a sustained traffic jam. This is what's working for me. If you prefer mechanical fans and copper/brass radiators and those are working for you, that's great.