There are way too many variables involved to answer the question here with anything other than ones opinion, PERIOD!!!
It is not just the material, a few of the other variables are, Fin Count, number of rows, are they staggered or not, are the fins louvered, thickness of the fins, how many fins per inch, how are the fins attached to the tubes, diameter of tubes, thickness of the tube walls, spacing between the tubes and on it goes.
I think to many people on here arguing about this subject think that a brass and copper radaitor has brass as part of the liquid cooling system, which it does not. The tubes and tanks are copper and the brass is the thin strips wedged between the tubes to suck heat out of the copper tubes into the air If aluminum radaitors weren't cheaper than copper radaitors are now do you think the car companys would use the aluminum in spite of the costs The aluminum radaitors are cheaper, not better
Last edited by Cab_Burge; 12/31/1504:32 AM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
If aluminum radaitors weren't cheaper than copper radaitors are now do you think the car companys would use the aluminum in spite of the costs 
The aluminum radaitors are cheaper, not better 