Fallwind that is pretty friggin sweet. Very nice job

Do you happen to know what make and model of car that rad is from, and/or who made it? I suspect it might just be an OEM pull, but I was pretty surprised when you said it was made out of brass and copper. Most car-type rads I've seen have been made pretty much exclusively out of aluminum.

Man with the size and kind of flow that thing has, I bet you could even do double or triple loops through just it with a simple manifold at the inlet and outlet and still reach the kind of delta you're seeing.