[ETsC10]

Here's my take on it...
First off JJ, aluminum radiators are dirt cheap so if you plan on getting one and it's coming in anywhere near the price of a copper radiator, keep looking.
BTW-copper is going up again so if you plan to buy, do it now.

I voted brass/copper but that is because I've got a fresh engine with cast iron heads and so I think
it is a better choice for the longevity of my engine. Besides, I already had my radiator.
I had mine custom built about a decade ago and had the core direction changed.
It has always been kept clean and has had the coolant swapped every couple of years.

Last summer during our rare 100+ summer heat my engine temps remained stable (fairly low)
regardless of driving/idling patterns.
However, I think if I had been running an aluminum radiator, it probably
would have performed well too because my block is
very clean inside and the peripheral systems have been set up right.

Regardless of what you choose, success is in the details:
A block with clean cooling passages, correct fit of your fan in the shroud, correct timing,
an appropriate fan, fresh correctly mixed coolant, the right thermostat ...

So...there's my 2 non-cents worth...

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