aluminum radiator for daily driver

Having worked at FLUIDYNE and now for Stewart Components I can tell you aluminum cores are stronger than copper brass because the aluminum tubes are extruded and the fines and tube sheets are brazed with a Nocolock furance. Cheaper cores use an epoxy to seal the tubes to the tube supports, which works ok but brazed is stronger. With copper/Brass they are soldered which is not as strong and does not transfer heat as well.

I would bet that there is some truth to core support flex and keep in mind radiators grow when they heat up, shrink when they cool down. Also radiators in todays cars last longer than they did before. I do not know of any copper/brass cores in production cars anymore. Alumium radaitors can be more expensive, just more skilled labor involved in producing them,unless you manufacture in large qaunities. Aftermarket radiators such as FLUIDYNE are hand TIG welded. I will use an alumium radiator in my 240Z when the time comes, right now the body work still drags on.